HomeMy WebLinkAboutMINUTES - 07061988 - T.1 THE_ BOARD OF SUPERVISORS OF CONTRA COSTA COUNTY, CALIFORNIA
Adopted this Order on llednesrjay, ,1111u 6, 19-89 , by the following vote:
AYES: Supervisors Fanden, Torlakson and Schroder
NOES: None
ABSENT: Supervisors Powers and McPeak
ABSTAIN: None
SUBJECT: Denial of Applications by L.E. Weisenburg on Final
Development Plan 3024-83 and Subdivision 6013 in the
Bethel Island Area and Rejection of Settlement
Agreement Relative to Delta Coves v. Contra Costa
County and L.E. Weisenburq v. Contra Costa County
On October 18, 1983, the Board of Supervisors denied the
applicant's appeal from the County Planning Commission's decision
denying the applications for Final Development Plan 3024-83 and
Subdivision 6013. Thereafter, the applicant filed a Petition For
Writ of Mandate in Superior Court on January 13, 1984 (Action No.
255111) , and a Complaint for Damages in U. IS. District Court on
October 14, 1986 (Action No. C-86-5842-MHP) .
The applicant, his counsel, County staff, and the County's
legal counsel in the two actions have engaged in negotiations to
reach a compromise settlement of the two lawsuits. After a
public hearing, the proposed settlement (if accepted) would
require the Board of Supervisors to approve the applications,
subject to specified conditions of approval, and to join the
applicant in requesting the U. S. Army Corps of Engineers to
issue a new permit authorizing the applicant to breach the
existing levee surrounding Bethel Island.
The applications and the proposed settlement came before the
Board of Supervisors on May 17, 1988. After a description of the
project site and a brief history by County staff, the Board
opened the public hearing. A summary of the comments made by
persons attending the hearing is set forth in the Board's Order
dated May 17, 1988. The Board continued the hearing to its next
meeting, on June 7, 1988, and subsequently continued it to June
28, 1988 to allow the Board members to visit the project site.
On June 23, 1988, a majority of the Board members viewed the
project site on a field trip.
On June 28, 1988 the Board held the continued public
hearing, and heard from a number of interested persons, both in
favor of and opposed to the applications, including Howard
Holmes, representing the Bethel Island Municipal Improvement
District ( "BIMID" ) , Douglas Flett, an engineering consultant
engaged by BIMID, Zach Cowan, an attorney representing BIMID,
Robert Thresh, a resident of Bethel Island, Timothy Donohoe,
representing the Sierra Club, L. E. Weisenburq, the applicant,
and Frederik Jacobsen, the applicant's attorney. At the
conclusion of testimony, the Board closed the hearing and
deliberated.
During the pendency of this matter, the Board received the
following documents into the record:
1) 5-12-88 memorandum from Harvey E. Bragdon, Director of
Community Development (Exhibit A) .
2) 6-16-88 memorandum from Robert C. Thresh (Exhibit B) .
3) 6-27-88 letter from People For Open Space/Greenbelt
Congress (Exhibit C) .
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1 4) 6-27-88 letter from Douglas B. Flett, D.B. Flett &
Associates, Inc. (Exhibit D) .
5) 6-28-88 letter from Zach Cowan, Attorney at Law
(Exhibit E) .
6 ) 6-29-88 [sic] letter from Mt. Diablo Audubon Society
(Exhibit F) .
7) Undated, hand-written comparison of road and park fees
required by the County on current land use applications on Bethel
Island with those required under the proposed settlement (Exhibit
G) .
8) 12-28-87 letter from Ray B. Krone, Ray B. Krone &
Associates, to John Scott (Exhibit H) .
9 ) 12-28-87 letter from Ray B. Krone, Ray B. Krone &
Associates, to John Scott (Exhibit I) .
10) Professional Record of Ray B. Krone and "Experience In
Water Related Housing and Commercial Developments (Exhibit J) .
11) 1-11-88 letter from William F. Jones, William F. Jones,
Inc. , Consulting Engineers, to John Houston- Scott (Exhibit K) .
12) 4-14-88 letter from William F. Jones, William F. Jones,
Inc. , Consulting Engineers, to John Houston Scott (Exhibit L) .
13) Curriculum Vitae of William F. Jones, P.E. (Exhibit M) .
The Staff recommended that the Board approve the settlement
agreement and stipulation for entry of judgment, which would
require certification of the Final Environmental Impact Report
prepared for 1832-RZ as adequate for these applications and
approval of the project applications.
After due deliberation, and in light of the record before
it and its view of the project site, on June 28, 1988 the Board
unanimously declared its intent to reject the proposed settlement
and to deny the project applications, and directed the staff to
prepare the appropriate documentation for its consideration.
NOW, THEREFORE, IT IS HEREBY ORDERED that the proposed
compromise settlement is rejected by the Board, the Final
Environmental Report prepared for 1832-RZ is not certified as
adequate for Final Development Plan 3024-83 and Subdivision 6013,
and said applications are hereby denied. Further, the Board
hereby finds and determines the following as bases for these
decisions:
1 . The Board finds that the project would constitute a
potential risk to life and property and a serious public health
problem, in that a sudden failure of the existing levee would be
likely to subject residents and owners of property along the
corridor between the existing levee and the project levee to
inundation by a wall of water which would be diverted toward them
and their properties by the project's perimeter levee.
2. The Board finds that the environmental impacts of the
project have not been studied adequately, based on circumstances
arising and information developed in recent years, in particular
within the last five years. The resistance of the existing levee
to erosion, in the area of the proposed breach, has been called
into question by, for example, BIMID's experience related to
dewatering in the course of a sewer project on the island.
3. The Board finds that the impact of the project on
subsidence of the island has not been adequately studied, in
light of recent information about the "greenhouse effect, " the
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resultant rise in Delta water level, and its potential detri-
mental effect on the stability and integrity of the existing
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Bethel Island levee near the proposed breach.
4 . The Board finds that correlation between the project and
seepage and groundwater migration has not been adequately
studied.
5. The impact of destruction of the existing wetlands on
the project site has not been studied adequately.
b. The Board further finds that the site is not physically
suitable for the proposed lagoon-type of development. The Board,
however, will consider other development proposals for the site,
which do not require the breaching of the existing Bethel Island
levee and which takes into consideration the existing sensitive
wetland areas.
7 . Further, the Board finds that the design of the proposed
project is likely to cause substantial damage to wetland wildlife
habitat.
These findings are substantially supported by information
and evidence not before the Board during its hearings in 1983,
including but not limited to the testimony of Howard Holmes
regarding recent Delta levee failures and of Douglas Flett, the
report submitted by Douglas Flett, and the Board members,
personal viewing of the project site.
Upon considering the record as a whole, the Board is unable
to find that the Final Environmental Impact Report prepared for
1832-RZ is adequate for the present project applications, and the
Board further finds that the construction of the project is
likely to be detrimental to the public safety of residents and
property owners in the vicinity of the project.
1 heresy certl!y that this Is a true and correct copy of
on action taken and entered on the minut •s of the
Board of Supervisors on the date shown.
ATTESTED; 2 01
PHIL BATCH R, C er: of the @card
.. of Supervisors and County Adr!in!str�!;or
By , Deputy
cc: Community Development
County Counsel
L. E. Meisenburg - Delta Coves
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�? $OARb OF SUPERVISORS
FRCM:_ Harvey E. Bragdon �.�o itra
I Director of Community Development Costa
MTE: May 12, 1988 coirty
SUBJECT: Hearing on the application by L.E. Weisenburg (applicant &
owner) , County File ; 3024-82 and Subdivision 6013 (Delta Coves)
for 495 single family residential lots, 65 townhouses, 140
A ( , 1
sPECIFIc RBouleva�rd and Stone Road in the Bethel Island area.
RECOMMENDATIONS
A. Open hearing, take testimony and evidence, close hearing, and
defer decision on the above applications until June 14, 1988;
B. Approve -settlement agreement and stipulation for entry of
judgment, which will require (after entry of judgment) :
1. Certification of the Environmental Impact Report
prepared for 1832-RZ as adequate for these associated
project applications.
2. Approval of Final Development Plan 3024-83 and
Subdivision 6013 as recommended with the attached
revised Conditions of Approval, which are part of the
negotiated settlement.
X
CONTINUED ON ATTACHMENT: YES SIGNATUR '
RECOMMENDATION OF COUNTY ADMINISTRATOR RECO ATION F 80/0
COMMITTEE
APPROVE OTHER
SIGNATUREIS y
ACTION OF BOARD ON APPROVED AS RECOMMENDED OTHER _
VOTE OF SUPERVISORS
HEREIrf CERTIFY THAT THIS IS A TRUE
UNANIMOUS (AOSEITT ) ND CCRPECT COPY OF AN ACTION TAKEN
AYES: _ NOES: _ AND ENTERED ON THE MINUTES OF THE BOARD
ABSENT: ^A BSTA I N: C:= SUPERV i SMS ON THE DATE SHOWN.
CC: ATTESTED
PHIL BATCHELOR. CLERK OF THE BOARD OF
SUPERVISORS AND COUNTY ADMINISTRATOR
BY
M382,'7-83 --- — -
,DEPUTY
Exhibit A
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CHRONOLOGY
f '
August 20, 1973 Application received for
ti rezoning & preliminary
development plan (1832-RZ) .
September 21, 1976 Board certifies Final EIR,
rezoned property to P-1, &
approved prelim. dev. plan.
1978-1982 Applicant commissions
additional environmental
studies.
May 11, 1982 Application received for
final dev. plan & tentative
subdivision map.
April 12, 1983 County Planning Commission
requires focused EIR.
June 21, 1983 Board of Supervisors denies
appeals of County Planning
Commission's decision.
July 26, 1983 County Planning Commission
denies 'the applications
(3124-83 and Subdivision
6013) w/o prejudice, because
of statutory deadline.
October .18, 1983 Board of Supervisors denies
appeal of County Planning
Commission's decision.
January 13 , 1984 Applicant files Petition For
Writ of Mandate in Superior
Court (DeltaCoves v. County
of Contra Costa)
October 14 , 1986 Applicant files Complaint For
Damages in U.S. District Court
(Weisenbura v. County of
Contrgi Costa)
BACKGROUND
The lawsuits over these projects prompted a review of this
project and subsequent negotiations regarding settlement.
The above chronology outlines actions taken on this project to
date. The essential events are that a Final EIR for the project
was certified in connection with the application for rezoning and
preliminary development plan. Durinq. the processing of the
current applications the applicant was required to prepare an
additional focused EIR addressing specific issues. The
requirement was appealed by both the applicant and a Bethel
Island citizens' group. The appeals were denied and the
requirement for the additional focused EIR upheld. Time had
elapsed at this point such that shortly after the Board of
Supervisors' hearing on the appeals, the County Planning
Commission was forced to deny the applications without
prejudice, due to statutory time limits.
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ANALYSIS
The purpose of the hearing is to obtain public comments
regarding the applications, in connection with the Board's
consideration of a proposal to settle both lawsuits arising out
of the County's requirement for an additional, focused EIR.
If the Board of Supervisors is to approve these applications, it
must make a CEQA determination on this project, since the Final
Environmental Impact Report for 1832-RZ was never certified as
adequate for the current applications. Thus, staff's
recommendation to approve the settlement would require the Board,
after the settlement is entered into, to certify the Final EIR
for 1832-RZ as adequate for this project.
The key issues involving the EIR are whether it should be used
for this project and whether there are any additional , reasonable
alternatives or mitigation measures that should be considered as
ways to avoid or reduce the significant effects of this project.
The majority of the conditions of approval prepared by the staff
in 1982-83 for these applications remain as originally proposed,
but they have been revised somewhat. The revisions primarily
reflect changes in the community needs, planning laws and other
factors that have occurred in the five years since the last
hearing on this project. In addition, to insure consistency, the
original conditions of approval were compared with those required
of the Connor project (Subdivision 6837) , as the latter
represents a major subdivision in the Bethel Island area. As a
result, the fees to be paid for roadway improvements and parks
were modified. Also added were the requirements to join a police
service special tax area and to develop a TSM plan. Other
modifications to the conditions, specific to this project,
include the provision for levee maintenance, a water quality
control plan, and provision for realignment of Sandy Lane and
Stone Road. The conditions of approval, as revised, are part of
the proposed negotiated settlement of the litigation.
In addition, the applicant has submitted to the Community
Development Department supplemental studies which address
several concerns expressed by the Board and the Planning
Commission during the earlier hearings. Specifically, the
applicant has commissioned Dr. Ray B. Krone to consider water
circulation and the possibility of flooding between the proposed
new levee and the existing levee. Dr. Krone's reports are dated
December 28, 1987. (Exhibit "I" to the Conditions of Approval)
William Jones & Associates has submitted a report, dated January
11, 1988, regarding the potential settlement of adjacent
properties that might be caused by the construction of the Delta
Coves project. (Exhibit "I" to the conditions of Approval) Mr.
Jones has also written a report, dated April 14 , 1988, addressing
the issues of liquefaction and the possibility of a "Stone Road
corridor effect. " (Exhibit "J" to the Conditions of Approval)
This department's staff reports to the Planning Commission, dated
February 22, 1983 and March 22, 1983, recommending approval of
the project applications, are on file with the Clerk of the
Board.
CONCLUSION
Staff (the Community Development Department and the County
Counsel's Office) recommends that the Board of Supervisors
approve the Settlement Agreement and the Stipulation For Entry of
Judgment, which require the Board (after a judgment is entered)
to certify the Final EIR for 1832-RZ as adequate for this project
and to approve the project as amended with the attached revised
conditions of approval .
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✓ CONDITIONS OF APPROVAL FOR 3024-82 & SUB 6013:
1. This approval is based on the Final Development Plan exhibits received by
the Community Development Department and modified by these conditions:
Exhibit "A"- Final Development Plan for 560 dwelling units as summarized in
the staff report.
Exhibit "B"- The Tentative Subdivision Map and Grading Plan.
Exhibit "C"- The Delta Coves Typical Lot and Dock Plans.
Exhibit "D"- The conceptual landscape architectural plans.
Exhibit "E"- Report on Investigation of Tidal Flushing, prepared by R. B.
Krone and Associates.
Exhibit "F"- The Soils and Geologic Investigation for Delta Coves prepared
by William F. Jones, Inc.
Exhibit "G"- "The Woodlanding Traffic Impact Study" prepared by TJKM, July
9, 1982.
Exhibit "H"- "Water Circulation of Project Waters" and "Delta Coves
Project--Flooding of the Bethel Island 'Corridor, '" December 28, 1987, pre-
pared by Ray B. Krone & Associates.
Exhibit "I"- "Settlement of Off-Site Improvements," January 11, 1988, pre-
pared by William F. Jones, Inc.
Exhibit "J"- "The Delta Coves Project, Bethel Island, CA," April 14, 1988,
prepared by William F. Jones, Inc.
The above exhibits are on file with the Clerk of the Board, and are incor-
porated herein by this reference, as if set out in full .
2. All land uses, yard and height measurements shall be subject to review and
approval by the Director of Planning.- The guide used to establish these
requirements shall be the R-9 Single Family Residential District of the
Zoning Code. Exhibit "C" indicates 15 ft. setback which is not granted
with this approval , but subject to review by the Director of Community De-
velopment.
.3. Proposed Covenants, Conditions and Restrictions, Articles of Incorporation
and by-laws for a mandatory homeowners' association shall be submitted with
the application for approval of a Final Subdivision Map for the first phase
of the project. These documents shall provide for establishement, owner-
ship, and maintenance of the common open space.
4. Detailed plans for the development of the commercial areas on Parcels D, E,
M, and N must be submitted for approval by the Planning Commission under
.the Final Development Plan procedures.
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5. The design of all the units in the condominium area, Parcel "B", shall be
subject to review by the Planning Commission as to layout design, building
plans and elevations, building materials and other pertinent physical fea-
tures.
6. The phasing schedule as shown on the tentative map is approved and may be
modified upon request to the Director of Community Development.
7. A deed of development rights shall be granted to the County for all open
space and common areas prior to filing of the Final Subdivision Map. The
grant of this deed is intended to preclude residential development of the
common areas. The deed of development rights is not intended to preclude
or prohibit owners or the homeowners' association from erecting in the com-
mon areas improvements such as (but not limited to) moorings, launching
ramps, gates, gas docks, and pilings.
8. A bridle trail may be developed on the periphery of the project at the base
of the levees(s) . A bike trail will be developed on the periphery of the
property at the top of the levee(s) . The designs of these trails shall be
shown on the development plan and will . be developed in increments with each
phase of the project.
9. Landscaping plans shall be submitted, for review and approval of the Zoning
Administrator, in accordance with the County' s Water Conservation Policies.
The landscaping of the common areas shall be accomplished during each phase
of development and coordinated with the erosion control planting of the
perimeter levee.
10. The perimeter levee shall be planted for erosion control according to the
recommendations of a qualified landscape architect, with plants requiring a
minimum of water and maintenance . The plans shall be approved by the Com-
munity Development Department and made part of the subdivision grading and
improvement plans. Maintenance of landscaping shall become the responsi-
bility of the Homeowners Association.
11. Levee design and construction specifications as shown on subdivision im-
provement plans and grading plans shall incorporate liquefaction-resistant
design acceptable to the Corps of Engineers. The developer shall obtain
the concurrence of the design and construction specifications from the
County Geologist, which concurrence shall not be unreasonably withheld.
12. Prior to breeching of the levee an automatically recording tide gauge or
other subsidence measuring instrument approved by the County Community De-
velopment Department shall be installed at a place in the marina area that
is protected from wave action. The gauge's foundation support will be
founded at or below elevation-25 and be designed to withstand lateral loads
from wind, seismic forces and water. Maintenance of the gauge will be re-
sponsibility of the Bethel Island Municipal Improvement District, or other
County-approved agency, or if necessary a Homeowner' s Association. The
developer, and eventually the Bethel Island Municipal Improvement District,
or a county-approved agency, shall work with the California Department of
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Water Resources to assure annual evaluation of the record obtained from the
gauge. For five years following installation of the gauge the record shall
be evaluated for subsidence annually, and a report shall be presented to
the Contra Costa County Water Agency during the month of January each year.
In succeeding years the record shall be evaluated at intervals specified by
the Bethel Island Municipal Improvement District, or a County-approved
agency, or if necessary, a Homeowner's Association. If at any time the
maintenance agency has reason to believe subsidence threatens the develop-
ment it shall report its finding to the Contra Costa County Water Agency
with recommendations to mitigate the hazard of flooding due to subsidence.
13. Prior to issuance of any County permit for work required as a condition of
approval the developer shall enter into a .consultant services agreement
with the County and Bethel Island Municipal Improvement District;or other
County approved agency for geotechnical field inspection and consultation.
The developer shall provide the necessary funds to reimburse the County for
the services of the geotechnical consultant.
The services performed by the consultant will include: 1) Submittal of
reports on geotechnical work accomplished by the developer; 2) Adequacy of
work accomplished; 3) Copies of results of test and observations performed;
4) Recommendations for any changes in developer's plans, specifications, or
work procedures so long as any such recommendations are based upon a spe-
cifically identified substantial change in circumstances; 5) Daily inspec-
tion and reports will be submitted to the Community Development Department
on whether the work has been satisfactorily accomplished in a manner that
will prevent appreciable settlement or subsidence of the installed facili-
ties, and if the work is not deemed satisfactory, recommendations that, if
implemented, would prevent appreciable settlement or subsidence. However,
the absence of the inspector shall not be grounds .for work stoppage.
14. Geotechnical work shall include levee breaching, soil and excavation
dewatering, removal , replacement and compaction of soil , on-site water de-
velopment, erosion control measures, and design and installation of subsi-
dence measurement.
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15. Grading permits shall be required for each phase. All grading and earth-
work plans, whether temporary or permanent changes, shall be reviewed and
approved by the County Community Development Department prior to issuance
of a permit.
16. All earthwork covered by grading permits for earthwork in excess of 50 cu-
bic yards shall be supervised by an engineer specializing in soil engineer-
ing. The developer will provide this specialist.
17. A bond guaranteeing satisfactory performance and completion of grading
shall be secured by the applicant prior to issuance of any permit covering
excavations or fills in excess of 50 cubic yards. The bond may be part of
any bond instrument required by an agency of Contra Costa County for public
or private facilities, except for archaeological excavation, and shall not
be duplicative of any other required bond.
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18. Comply with the requirements of the Bethel Island Fire Protection District.
19. All utilities shall be placed in an underground system except for portions
of the property within a Flood Hazard Area. The development shall be ser-
viced by a cable television underground system. No television antennas
shall be permitted.
20. The individual dock shall be installed by the homeowner when each residence
is constructed for the associated lot in accordance with the design and
requirements of the C.C. & R. 's.
21. The portion of Stone Road affected by the breaching of the levee shall be
abandoned before construction begins.
22. The developer shall obtain a resolution from the Bethel Island Municipal
Improvement District, or county-approved agency, or, if necessary, a Home-
owner's Association which shall indicate the district's agreement to accept
and maintain the new levees and lagoon.
23. If archaeologic materials are uncovered during grading, trenching or other
on-site excavation, earthwork within 30 meters of these materials shall be
stopped until a professional archaeologist who is certified by the Society
for California Archaeology (SCA) and/or the Society of Professional Archae-
ology (SOPA) has had an opportunity to evaluate the significance of the
find and suggest appropriate mitigation measures, if they. are deemed neces-
sary.
24. Plans for the development of the recreation center and its ownership and
maintenance shall be provided to the staff for review and approval after
the sale of 250 homes.
25. Prior to the filing of the Final Map, the applicant shall prepare a lagoon
Management Program designed to maintain the lagoon water quality to a level
at least as high as the water quality in the surrounding sloughs.
26. All street names are subject to review and+approval by the Community. Devel-
opment Department prior to recording the Final Subdivision Map.
27. Obtain a Floodplain Permit and elevate the lowest finished floor of the
proposed structure to above the base flood- elevation. The applicant is
requested to observe an additional 2 feet of freeboard above the base flood
elevation due to anticipated wave action and unknown factors that could
contribute to greater flood heights.
28. The entrance to Sandmound Slough will be designed, to the extent practica-
ble, to minimize and mitigate silting and wave action from existing boat
traffic to the entrance and to berths adjacent to the entrance. The design
will be submitted to the County Community Development Department and the
Corps of Engineers.
29. Comply with the Department of Public Works requirements as follows:
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A. In accordance with Section 92-2.006 of the County Ordinance Code, this
subdivision shall conform to the provisions of the County Subdivision
Ordinance (Title 9) . Any exceptions therefrom must be specifically
listed in these Conditions of Approval .
B. All interior subdivision streets shall be dedicated to the County and
constructed to County public road standards.
C. Contribute $1,800 per unit to a Road Improvement Fee Trust (Fund No.
819200-0800) designated for road improvements along Cypress Road
and/or Bethel Island Road between State Hwy 4 and this development.
D. Design and construct the storm drainage system so that the flow line
of the outlet pipes is above mean sea level .
E. The minimum top of levee elevation of the perimeter .levee shall be at
10 foot USGS datum.
F. Improve and protect all levees with rock or an alternate method ac-
ceptable to the Public Works Department, prior to the breaching of the
Bethel Island Levee.
G. The developer shall install an adequate lagoon flushing system ap-
proved by the PublicWorksDepartment.
H. Comply with the requirements of Sanitation District No. 15 as follows:
1. Sewer Collection System
a. The District has been able to reduce the inflow/infiltration
so that there should be sufficient capacity in the system to
service the proposed 560 dwelling units. The developer will
be given credit for the money previously paid towards the
District's connection charge.
b. The treatment plant has been constructed and the Oakley
Bethel Island Wastewater Management Authority will provide
treatment capacity in accordance with its policy.
C. The funds for expanding the treatment facilities are provid-
ed for by the Facilities Capacity Fee that is charged for
each connection.
d. Construct a monitoring and metering manhole at a mutually
agreed upon location. The manhole shall be equipped with
monitoring and flow metering equipment, all approved by the
District prior to construction and installation.
2. Water System
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a. Submit a detailed comprehensive plan for water service. The
Final Map shall not be recorded until this plan is approved
by the District and County Health Department, State Health
Department and Planning Geologist.
b. Conform to "AWWA Standards" published by the American Water
Works Association for materials and construction of the wa-
ter system.
C. Equip each potable waterwell with chlorination facilities, a
water meter and a spare water meter.
d. Provide the water system with standby . power on both pumps
with automatic switchover to provide adequate backup for
failure of wells, pumps and power.
e. Conform to the drinking water standards of the State of Cal-
ifornia Department of Health and provide any necessary
treatment facilities to meet these standards.
f. All cross connections to the water system are prohibited.
g. Backflow prevention devices shall be required on all service
lines.
h. Obtain approval from the Bethel Island Fire Protection Dis-
trict and the Board of Fire Underwriters on the fire hy-
drants.
3. Water and Sewer System
a. Conform to Contra Costa County Sanitation District No. 15
ordinances and requirements for sanitary sewer and water
facilities serving the development.
b. . Plans and specifications for the sanitary sewers and the
water supply and distribution system shall be approved the
District prior to issuance of any building permits.
C. Execute an improvement agreement between Sanitation District
No. 15 and the developer with respect to the water .and sew-
erage facilities and bond for the Water and Sewer Systems.
Any such bond shall not be duplicative of other required
bonds. The developer shall be responsible for correcting
any damage to existing facilities caused by this project.
d. The developer shall install sewer and water systems that
meet the approval of Sanitation district No. 15 and dedicate
the systems and all required access and maintenance ease-
ments to the District.
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{ e. Construct the main sewers and the water supply and distribu-
tion system in:
1. Easements or fee title dedicated to the District; or
2. In the County road right of way.
f. Each individual living unit and commercial unit shall be
served by a separate water service and sewer lateral .
g. Certification that the soils will support the sanitary
sewers (maintain grade) and the water distribution system
and all appurtenances to the systems by an engineer regular-
ly engaged in the field of "soils engineering."
h. Structures and trees are not allowed to be over sewer and
waterlines. This restriction shall be stated in the Grant
of Easement.
I. Furnish proof to the Public Works Department, Engineering Services
Division, of the acquisition of all necessary rights of entry, permits
and/or easements for the construction of off-site, temporary or perma-
nent, road and drainage improvements.
J. Construct pavement1widening to provide a 22-foot interim half-width
roadway with longitudinal and transverse drainage along the frontage
of Gateway Road between Stone Road East and Bethel Island Road.
K. Convey, to the County, by Offer of Dedication, 12 feet of additional
right-of-way on Gateway Road as required for the planned future width
of 84 feet.
L. Convey to the County, by Offer of Dedication, 5 feet of additional
right-of-way on Stone Road as required for the planned future width of
60 feet.
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M. Realign Sandy Lane so the center line is opposite the center line of
Cottage Lane. If the applicant is unable to obtain adequate right-of-
way, he shall request the county to enter into condemnation proceed-
ings.
30. Building numbers shall be illuminated and posted in a position visible from
the street.
31. Applications for building permit approvals for multiple family residential
projects will indicate a suitably enclosed area for the purpose of locating
recycling bins for paper, glass and cans. For projects of 50 units or
less, such area will not be less than 10 feet by 12 feet in area, and the
enclosure shall be at least six feet high. For projects of more than 50
units, proportionately greater areas will be required. This area will be
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included in the computation of the 25 percent of lot "open area" required
of such development plans.
32. Comply with the requirements of the Bridge/Thoroughfare Fee Ordinance for
the East/Central County Travel Corridor Area of Benefit as adopted by the
Board of Supervisors by paying $380 per unit.
33. On the provision of police service, the applicant agrees to vote its prop-
erty into a "special tax area" for police service at an initial level of
$100 perparcel annually. This amount shall be adjusted yearly according
to the Bay Area CPI. Furthermore,. the Board of Supervisors shall review
the assessment amount and adjust it to a higher level as conditions warrant
it. Review shall be made of the initial assessment amount after budget
hearings and after the pending elections of the general community on the
question of additional police services.
34. Prior to the issuance of building permits the applicant shall comply with
the provisions of Ordinance No. 87-95 as of the date the tentative subdivi-
sion map is approved. An approved TSM plan shall be operative prior to
final inspection by the Building Inspection Department.
35. The applicant shall add the following to the deed of each newly created
parcel :
"This document should serve as notification that you have purchased
land in an agricultural area where you may regularly find farm equip-
ment using local roads, farm equipment causing dust, crop dusting and
spraying occurring regularly, burning associated with agricultural
activities, noise associated with farm equipment and aerial crop dust-
ing, and certain animals and flies may exist on surrounding proper-
ties. This is, again, notification that this is part of the agricul-
tural way of life in East Contra Costa County and you should be fully
aware of this at the time of purchase."
36. The applicant shall pay a traffic mitigation fee of $100 per unit to miti-
gate impact of traffic through the Oakley area.
37. The applicant shall comply with the Park Dedication Ordinance as follows:
$850 per unit for the last 250 units and $400 per unit for the remain-
ing units.
38. The fees required by conditions 29C, 32, 36 and 37 shall be paid at the
time building permits are issued.
KK/df
GenA:3024-82.kk
a
May 17 , 1988
SUPPLEMENT TO DELTA COVES CONDITIONS OF APPROVAL
(DP #3024-82., Subd. #6013 )
Condition #6 is amended to read as follows:
116. The phasing schedule for the residential lots as
shown on the tentative map may be modified by the
Director of Community Development upon request of the
developer. The perimeter levees will be constructed in
three phases. They will be constructed in parallel so
as to allow the construction of a cofferdam, if
necessary, at the completion of either of the first two
phases. Construction of the perimeter levees shall be
completed within seven years of ground-breaking for the
project. This seven-year period shall be tolled for
any of the following reasons:
(a) Acts of God;
(b) Natural catastrophes;
(c) Acts o'f war;
(d) External conditions beyond the developer's control
which, in the opinion of the Director of Community
Development, substantially interfere with the developer's
ability to construct and/or market the subdivision;
(e) Unreasonable delays attributable to governmental
action or inaction, including but not limited to delays in
granting grading permits;
(f) Labor strikes or slow-downs;
(g) Vandalism;
(h) Other unforeseen conditions beyond the control 'of
the developer which interfere with levee construction.
SETTLEMENT AGREEMENT
This Settlement Agreement is made and entered into this
day of May, 1988, by, between, and among Delta Coves, a
California limited partnership and L.E. Weisenburq, Jr. , general
partner of Delta Coves (hereinafter collectively referred to as
"Delta Coves'') and the County of Contra Costa (hereinafter
"County") .
It is the purpose of this Settlement agreement to settle,
discharge and conclude all disputes between the parties as well
as settle the litigation entitled Delta Coves v. Contra Costa
County, Contra Costa Superior Court No. 23511 (hereinafter the
"State Lawsuit") and Weiaenburar v. Contra Costa County, USDC
No. C-86-5852 MHP (hereinafter the "Federal Lawsuit") .
In consideration of the mutual promises and covenants of the
parties heroin, and for other good and valuable consideration set
forth below, the parties agree as not forth herein. Such
consideration includes, for Delta Coves, the avoidance of the
expense and delay of prosecuting this action and the Federal
Lawsuit, and of the possibility of losing one or both of such
actions. Such consideration includes, for the County, the
avoidance of the expense of defending this action and the Federal
Lawsuit, and of the possibility of losing one or both of such
actions. Specifically, such consideration also includes the
avoidance of risk of the County losing the Federal Lawsuit and
- 1 -
• T `
a
y paying significant damages and possible litigation expenses to
Delta Coves.
1. A=roval of Project. The County will approve the
application filed by Woodhill Development Company on May 13,
1982, and as revised and resubmitted by Delta Coves on
November 20, 1982 for Final .Development Plan and Tentative
Subdivision Map, subject to the following modifications:
a. The conditions to be imposed on the subdivision are
attached hereto as Exhibit A.
b. The conditions listed in Exhibit A shall not be
changed or modified without the written consent of Delta Coves.
Specifically, the fees listed in paragraphs 29C, 32, 36 and 37
shall. not .be increased bylthe County at any time, nor shall any
additional fees of any kind be imposed including but not limited
to (1) fees as conditions for development approval, and (2) fees
as conditions for the issuance of building permit(s) .
CO The County accepts the reports of Dr. Ray Krone and
William F. Jones identified in paragraph l of Exhibit A in
satisfaction of any requirement to further study geotechnical
aspects of the subdivision.
2. Time of the Essence. The parties .understand and agree
that time is of the essence in this matter. The County
(including the Board of Supervisors and Planning Department
Staff) hereby agrees to fully cooperate with and join Delta Coves
in requesting the U.S. Army Corps of Engineers to reissue the
2 -
I
permit for the breach of the Sand Mound Slough levee without need
for a now -or supplemental EIB. The parties understand and agree
that upon the approval of the tentative subdivision map and final
development plan, Delta Coves may proceed immediately with the
subdivision while the request to the Corps is pending. The
parties further understand and agree that Delta Coves may rescind
this Settlement Agreement, and pursue all available legal
remedies, if the corps does not reissue the permit on or before
October 1, 1988.
3. Dismissal. Delta Coves and L.E. Weisenburg, Jr. will
file a dismissal without prejudice of the Federal Lawsuit upon
execution of the settlement Agreement. Delta Coves and
L.E. Weisenburg, Jr. will file a dismissal with prejudice of the
Federal Lawsuit when the County approves the tentative
subdivision may and the final development agreement and the corps
of Engineers issues its permit(s) to allow the levee to be
breached and the new project levees constructed. Each party will
bear its own costs of suit.
4. Miscellaneous.
a. C2=lete Agreement. This Settlement Agreement
contains the entire agreement of the parties and may be modified
.or amended only by a written instrument executed by each party
hereto.
3 -
b. severability. If any portion of this agreement
shall for -any reason be unenforceable in any respect, such
unenforceability shall not affect any other provision hereto.
c. Attorneys' Fees. In the event of breach of this
Settlement Agreement or the need to enforce it, the prevailing
party in any action thereon shall be entitled to its costs and
attorneys' fees.
d. affected persons. This settlement Agreement
governs the rights of and binds and insures to the benefit of
each of the parties and their respective successors, assigns,
employees, agents, purchasers, tenants, administrators,
executors, heirs and attorneys, and all others acting on their
behalf or on behalf of any of them.
e. Admissions. , Lxcept for the .judgment that the
parties will stipulate to in the State Lawsuit, nothing contained
herein shall constitute any admission of liability on the part of
the County or any .admission by Delta Coves .that its claims in
either the State .Lawsuit or the Federal Lawsuit are without
merit. Specifically, the parties agree that the judgment, but
not the stipulated facts, will be admissible against the County
in the Federal Lawsuit. Both the judgment and the stipulated
facts will be admissible in any litigation involving third-
parties. Both parties merely intend by their actions pursuant
hereto to avoid prolonged and further litigation.
4 -
IN WITNESS WHEREOF, the parties hereto have caused this
Settlement. Agreement to be duly executed as of the dates .belo*w:
Dated: , 1988 DELTA COVES, a California
Limited Partnership
By.
L.E. WEISENHURG, JR.
General Partner
Dated: , 1988 COUNTY OF CONTRA COSTA
BY:
• ROBERT SCHRODER,
Chairman,
Board of Supervisors
ATTEST: PHIL BATCHELOR,
Clerk of the Board of supervisors
and County Administrator
By:
Deputy
APPROVED AS TO FORM:
VICTOR J. WESTMAN,
County Counsel
BY:
FAJ:Mp:872jo/1177
5 -
AGENDA ITEM
'' t1
for
(date
-TO: CONTRA COSTA COUNTY BOARD OF SUPERVISORSRE
" r. ;H D
RE: DELTA COVES
JUN : }�
FROM: ROBERT C. THRESH , 364 Park Lane , Bethel Island , 1A 94511.
DATE: JUNE 16 , 1988 r"` " "C° oe
po
T If
AS PRESENTLY WRITTEN , DRAFT CONDITIONS OF APPROVAL FOR DELTA COVES (3024-82
& SUB 6013) IGNORE AND CIRCUMVENT THE POWERS AND AUTHORITY OF THE BETHEL
ISLAND MUNICIPAL IMPROVEMENT DISTRICT AS AUTHORIZED BY THE STATE.
Several of .the conditions contain the wording "Bethel Island Municipal
Improvement District , or other County-approved agency . " Apparently the
author of the Draft Conditions was not aware that B. I .M.I .D. cannot be
supplanted by a county agency in this manner .
Condition 22 says "The developer shall obtain a resolution from the Bethel
Island Municipal Improvement District , or county-approved agency , or , if
necessary , a Homeowners Association which shall indicate the district ' s
agreement to accept and maintain the new levees and lagoon. "
BIMID has the sole power to accept and maintain levees within its
boundaries .
The improvement district was created by an act of the -state and has almost
all the powers granted to a city . The following is a brief summary of the
enabling act :
Bethel Island Municipal Improvement District Act
In 1960, the State of California passed an act which created the Bethel
Island Municipal Improvement District prescribing its boundaries ,
organization , and powers . (Statutes of California , Chapter 22) The act
became operative when voters in the district approved it by a majority
vote .
The enactment gave the boundaries and the acreage (3516. 54 acres) of the
Island in the unincorporated territory of Contra Costa County .
In Article .5. Powers , (Sec . 78) it states , "The district gay acquire ,
construct , maintain , and operate works , improvements , and facilities for
the reclamation of submerged or other lands by watering or dewatering ,
including grading , excavation , fill , levees . . .and all works and facilities
incidental to or necessary or useful therefor .
And , in the same article (Sec . 96) it states , "The district ma-v make and
enforce all necessary and proper regulations . . . for the supplying of
reclamation service . . . .A regulation of the board shall be adopted by
ordinance. . . "
Further in the same article (Sec . 100) it states , "The reclamation district
[Reclamation District 1619] is merged with the district [ B. I .M.I .D. ] . . . "
Exhibit B
� 1
page 2 -- MEMO FROM R . THRESH, RE DELTA COVES , 6/16/88
The reasons for the. formation of B. I .M. I .D. were set out in Article 17.
Among them were the following : "that the area benefited may be provided
with various municipal improvements . . .accomplishment of this purpose is
impossible under existing general laws and therefore special legislation is
necessary . . . .The area is protected by a system of levees from overflow by
water . With a population of 2 , 500, there is urgent need to supplant the
reclamation district with a popular vote form of district . . .There are no
existing general laws under which the area could be provided with the
facilities it needs short of incorporation as a city . . . "
In December of 1977 , B. I .M. I .D. , under the powers granted to it by the
enabling act , passed Ordinance 9 . This ordinance regulates and controls
alterations to and encroachments upon , through, or over the District ' s
levee system.
. Section IV of the ordinance reads in part , . "No person shall and it shall be
unlawful for any person to do any of the following (all of which are deemed
encroachments) : grade , level , fill , widen, raise , cut , dig , disturb or
remove rocks . . .or place , erect , construct or maintain any . . .building ,
structure or works of any kind upon or over— .any levees or flood control
works of or within the District . . .except when expressly permitted to. do so
by a proper and revocable written permit , easement or agreement executed
between said person and the District and upon payment to the District of
any required fees , expenses , rental , or other compensation therefor . "
In Section VII of the ordinance it states , "Approval of any permit by the
Board of Directors . . . pursuant to this ordinance shall be contingent upon 1 )
the applicant agreeing to assume all liability resulting from the proposed
installation. . .and 3) the applicant complying with any other conditions
which the Board or committee of the Board in its descretion may from time
to time deem appropriate .
The conditions of approval for Delta Coves should be corrected to reflect
BIMID' s authority in these matters . Furthermore , a new condition (similar
to #18) should be added which reads, "Comply with the requirements of the
. Bethel Island Municipal Improvement District and .pay all district fees . "
Another condition which would assure compliance with BIMID's Ordinance 9
requiring the applicant ' s assumption of all liability , could read as
follows, "The applicant must obtain an insurance policy with tail coverage
which fully protects all Bethel Island property owners from any loss due to
the project . "
cc : BIMID Board of Directors
People for ®pen Space/
Greenbelt Congress
116 New Montgomery Suite 640 • San Francisco CA 94105 • (415) 543-4291
June 27, 1988
Robert Schroder, Chairman RECEIVED
Contra Costa Board of Supervisors
651 Pine Street
Martinez, CA 94553 JUN V1988
PHIL BATCHELOR
Re' Delta Coves Project CLERK BOARD OF
CONTR
ACOSTA CO
Deputy
Dear Chair Schroder and Members of the Board:
People for Open Space supports denying the Delta Coves project and not
certifying the Environmental Impact Report.
Approval of the project would set a dangerous precedent for the county.
o It is between two levies that could rupture and flood the community,
thereby making the county liable for damages.
o It is in an area that could be flooded with rising sea levels
attributed to the greenhouse effect.
o The environmental review has not been adequately evaluated the
cumulative impact of development in the area including Oakley,
Brentwood, and the proposed Bethal Island Specific Plan. Environmental
review should look at the cost of infrastructure, impact on air quality,
and impact on agriculture and open space.
o The area is important wetland habitat. The California legislature
adopted a goal of increasing California's wetlands by fifty percent.
Contra Costa County should work to help implement that goal.
Sincerely,
Mark Evanoff
Field Coordinator
Exhibit
BOARD OF DIRECTORS ADVISORY COMMITTEE
Resident Contra Costa County San Mateo County Howard Allen Robert Kirkwood EXECUTIVE DIRECTOR
Robert Mang' Paul De Falco' Kit Dove Leslie S.Ayers Melvin B.Lane Larry Orman
Vice Presidents Michael Gleason Bob Girard . Bob Augsburger Putnam Livermore ASSOCIATE DIRECTOR
David Bomberger' Laura Selfridge Clarence E.Heller Lucy Blake Larry Livingston
Lennie Roberts Joseph Judith Kunofsky
Barbara Eastman' Morin County p Bodovih Pomelo Lloyd
William D.Evers' Don Dickenson' Joel W Schreck Lewis H.Butler Irwin Luckman
Clement Shute' Bonnie Mitsui Santa Clara County Louise Davies Jane McKenzie
Secretary-Treasurer Ellen Straus Pat Compton Laurence Dawson Syivio McLaughlin
Jerry Tone' Napa County Linda Elkind Rene di Rosa Theodore Osmundson
Volker Eisele' Enid Pearson Mort Flelshhacker Ned!R.Peirce Founder.
Jay Goefting Solana County June Foote Mel Scott Dorothy Erskine
Alameda County San Francisco Bob Berman* Eileen R.Growald George A Sears (1896-1982)
T.J.Kent,Jr. Alfred Heller Mrs.William Siri
Roberta Borgonovo Sonoma County
Jerry Tone I.Michael Heyman Wallace Stegner
Renate Woodbury Mary Jane Brinton George Eltmon James Hobbs Mrs.Carl W.Stem
Gary Zimmerman Andrew Butler Dee Swonhuyser Lois Hogle John H.Sutter
ZachJohn Cowan Joe Johnson Mrs.Otto H.Teller
John Erskine 'Executive Committee Huey Johnson
Bud Johns' Member
" A
CIVIL ENGINEERING
D. B. FLETT & ASSOCIATES, INC. 1280 Civic Drive, Suite 210, Walnut Creek, CA 94596 (415) 935-7710
June 279 1988
Contra Costa County Board of Supervisors
651 Pine Street jRECEIVEL)
1st Floor , North Wing 1�. `�••j�,j ,�,J
Martinez , CA 94553
JUN pe 1988
Subject : Subdivision 6013 (Delta Coves )
PHI AJCHEI
RK DOR ORS
Honorable Supervisors , co
9 Deputy
We have been retained by Bethel Island Municipal Improvement
District (BIMID) to review the proposed Subdivision 6013 and its
impact on the existing and future Bethel Island Levee System.
In completing this review we have examined the Soils and Geologic
Investigation, EIR, several recent California Department of Water
Resources reports published between 1982 and 1986, and other
documents listed in the attached bibliography . In addition we
have consulted with Board members and staff of BIMID.
BIMID's primary concern, is the safety and integrity of the levees
which form and protect Bethel Island . The Bethel Island Levee
System is probably one of the best system, in the Delta. The
Corps of Engineers estimated the statistical frequency of the
Bethel Island levee failures to be 0.20 failures per 100 years in
1974. However , the Corps also indicated that without a levee
improvement project after BO .years, the frequency of failure
would rise to 4.29 failures per 100 years, or about once every 25
years. BIMID's mission is to improve and maintain the existing
levees so that levee failures do not occur .
Historically, Bethel Island levees .have not failed since 1907.
Although there is some recollection of a possible failure in the
1930's, the only documented failure is one that occured in .1907.
The location of the 1907 break however , was near the site of the
breach proposed by Subdivision 6013. It is this concern for the
levee system which has caused BIMID to request that Subdivision
6013 not be approved in its present form.
In the last 6 years several additional studies of Delta Islands
and levees have been completed by the State of California,
Department of Water Resources (DWR) and additional data affecting
the levee integrity have become available. As a result of this
information BIMID has concerns in the following areas:
I . STABILITY OF THE EXISTING LEVEE:
A. The April 1984 Nonproject Levee Hazard Mitigation report by
DWR lists the following principal causes and , contributing
factors for levee failures:
Exhibit D
r Principal causes of levee failures are:
* Structural failure of levee by surface erosion or
internal erosion (piping ) .
* Foundation failure of underlying soils.
Overtopping by floodflows, tides, and waves.
Contributing factors include:
Improper levee design or construction.
Poor construction or foundation material .
Erosion by current and wave .ac.tion..
Seepage through or under the levee .
* Rodent burrows in the levee.
Improper levee repairs.
Improper structures placed in or on levee.
* Lack of regular and adequate maintenance.
The 1980 soils report fo'r the project indicates that the .existing
levee near the entrance channel area and for almost one mile
along Stone Road is underlain by up to 10 feet of peat . It is
recognized that this foundation condition is less favorable than
in other areas of the project .
Two possible causes of failure of the existing levee related to
the construction of Subdivision 6013 which are of concern to
BIMID are:
a . Structural failure related to internal erosion. - The
1980 borings actually encountered a void in the levee.
Although the soils engineer -declined to speculate on
the reason for the cavity's existence he did suggest
that there must be other cavities in the existing
levee .
It is possible that these cavities are evidence of
internal et-osion. Neither the 1980 soils report , the
1976 EIR or the 1988 letter .from Mr . Jones addresses
the impact on internal erosion resulting from lowering
the water table to facilitate construction of the new
levees. BIMID's experience with dewatering on a much
smaller scale for the installation of the Bethel Island
sewer system indicates that this may be a significant
problem.
D.B. FLETT& ASSOCIATES,INC. 1280 Civic Drive,Suite 210,Walnut Creek,CA 945% (415) 935-7710
b . Foundation failure of underlying soils. - Given the
fact that about 1 /2 mile of the existing levee is
founded on peat and that the 1907 levee break occurred
in this area , BIMID is concerned that any additional
weight on the levee or increase in the water pressure
caused by lowering of the water table inside the levee
may result in a failure of the poor foundation
material . Between 1983 and 1986 there were over 25
levee failures in the delta , most of which were a
result of structural or foundation .failure rather than
overtopping . Some of these failures occured during the
summer when repairs were being made to the levees and ,
the weight of the levee exceeded the strength of the
underlying foundation.
II . SUBSIDENCE RELATED ISSUES:
A. Levee Subsidence.- As part of the increased levee
maintenance and improvement program in the delta, BIMID
completed a survey in September 1987 of the existing
centerline profile and levee cross sections . Comparison of
this data with earlier data indicate that the levee
centerline is subsiding at a rate of about 1 to 2 inches per
year .
BIMID deals with this subsidence by continual maintenance of
the levees which' requires that the levees be constantly
raised . For this reason BIMID has adopted a rule
prohibiting structures within 50 feet of the centerline of
an existing levee. The proposed plan for Subdivision 6013
locates residences in this area making maintenance of the
new levees more difficult .
B. Deep seated subsidence. - DWR Bulletin 182-82 indicates that
there is deep seated subsidence in the vicinity of the Rio
Vista gage that may be permanent and .on-going . DWR began a
Delta Subsidence Investigation in July of 1965. Specific
data relating to Bethel Island is inconclusive in regard to
the rate of subsidence. At this date a deep subsidence well
has been drilled on the island , but instrumentation has not
yet been installed . The actual subsidence rate has not been
determined .
C. Sea Level Rise. - The BCDC sea level rise study is. the most
recent study available. An analysis of the tide level gage
at the Presidio in San Francisco indicates that the rate of
rise of sea level over the last 100 years has been 0.0039
feet per year . More aver , this rate appears to have
increased to 0.0072 feet per year in the last 19 years .
This report concludes that when the sea level rise is
coupled with deep subsidence the relative mean sea level
projection for Pittsburg for the year 2037 (50 years from
the date of the report ) is 0.8 feet above the present level .
In view of the relative increase in sea level , the BCDC
D. B. FLETT& ASSOCIATES, INC. 280 Clvk Drive, Suite 210, Walnut Creek,CA 94596 (415) 935-7710
report is recommending a sophisticated approach to the
determination of. levee height in order to provide protection
to the new structures. The existing project plan has not
considered this data, nor developed a method of providing a
continual levee protective device over the life of the
project . The conditions of approval do require monitoring
for possible subsidence, but do not require development and
implementation of a plan for controlling settling and
subsidence.
The conditions of approval call for a levee height of 10 ft .
This may or may not be adequate for the present conditions
when allowance for the .still water height and wave runup is
made. Under likely future conditions it is most probably
inadequate.
It should also be noted that raising the floor level of
structures protected by the levee above an elevation derived
by adding a freeboard allowance to the expected maximum high
tide does not provide adequate protection. Especially if
the ground on which the structure rests subsides.
On the other hand it is not necessary that the minimum floor
level be above the top of the levee. BCDC recommended
criteria require that the structure be floodproof, floor
level be above maximum still water elevation, and levee
crest above maximum water surface elevation.
r •
III . CHANGED GROUNDWATER CONDITIONS:
The DWR Flood Hazard Mitigation Plan prohibits dredging
material below -35 feet for levee repair or restoration
within 135 feet of the centerline of the levee. The reasons
for this relate to levee stability and a concern regarding
seepage when the impervious river bottom layer of silt is
removed . The removal of soil within the proposed lagoon may
have a similar effect . Furthermore, - subsequent filling of
the lagoon may alter seepage patterns elsewhere on the
island and thereby impact BIMID's seepage control program.
It is recognized that soil removal will not be as deep as
-35 feet. However , recent experience with dewatering for
installation of the Bethel Island sewers and subsequent
infiltration problems have caused BIMID to be concerned
about this factor .
There does not seem to have been any study or
consideration given to the effects of flooding a significant
area of the island . Therefore, it is BIMID's position that
the project as proposed not be approved .
In summary , BIMID opposes approval of the project as
proposed based upon new data relating to changed
circumstances since the last review of the project . These
4
D. 8. FLETT& ASSOCIATES, INC. 1280 Civic Drive, Suite 210, Walnut Creek, CA 945% (415)935-7710
data relate to :
1 . Stability of the existing levee under conditions
created to facilitate the construction of the levees
for Subdivision 6013,
2. Lack of consideration for maintenance of the new levees
required to offset the effects of sea level rise and
subsidence, and ,
3. Lack of consideration of seepage and groundwater
migration resulting from the creation of the new
lagoon.
Thank you for your consideration.
Sincerely , _
Douala-- B. Flett
RCE # 15227
5
P. B. FLETT & ASSOCIATES,INC. 1280 Civic Drive, Suite 210,Walnut Creek, CA 945% (415)935-7710
Zach C Attorney At Law
66 MINT STREET • SAN FRANCISCO, CALIFORNIA 94103 (415 l 543-2627
Contra Costa County-Board of Supervisors
County Administration Building
P.O. Box 911
Martinez, CA 94553 June 28, 1988
Re: Delta Coves
Sup.Ct.No. 255111
Dear Supervisors:
This office serves as District Counsel for the Bethel Island Municipal
Improvement District, and in that capacity, submits the following comTents for
the record with respect to your decision on the Delta Coves project and the
certification of the Environmental Impact Report (EIR) on that project (SCH #
74051339).
The District strongly opposes the staff recommendation to approve certify
the EIR and approve the project as proposed, and strongly opposes the Delta
Coves proposal on both procerdural and substantive grounds. While BIMID is cogni-
zant of the litigation between the developer and the County, it does not believe
that it should have to pay for mistakes made by the County years ago (approval
of the rezoning and preliminary development plan in 1976, and failure to process
the application quickly enough in 1983). However, if the County approves the
project now, it will set a precedent for development on Bethel Island which will
gravely endanger the residents of the Island and destroy BIMID's ability to
adequately maintain its levees.
I. The Conditions of Approval Violate the BIMID Act
In 1960 the Legislature enacted stautes chapter 22, creating BIMID (the
BIMID . Act). BIMID primary function under the Act is the maintenance and opera-
tion of the levees around Bethel Island. This function was entrusted to BIMID by
the state, and may not be usurped by the County. However this is precisely what
several of the conditions of approval seek to do.
The County's conditions of approval purport to permit the developer to
breach BIMID's levee. The County does not have this power. It has neither owner-
ship of the levees nor any easement rights over them. In addition, the condi-
tions purport to grant to the County full control over future activities re-
garding the levee.
While several conditions require compliance with regulations of the Bethel
Island Fire Department (#18) or Sanitary District 15 (#29H), and require payment
of various fees (#29C, 32, 36 [traffic], 33 [police] 37 [parks] ) which are to
paid when building permits are issued (#38), nothing in the conditions clearly
requires compliance with BIMID regulations, payment of BIMID fees (usually also
when building permits are issued), or compensation of BIMID for its costs as-
sociated with the development.
Exhibit E
1
s
Condition 11 requires concurrence of the Corps of Engineers and the County
Geologist in the design of the levees for Delta Coves, but not BIMID. Since
BIMID will (presumably) have the burden of maintaning, rehabilitating and re-
pairing those levees, and since BIMID will (definitely) be sued if those levees
break, the omission of BIMID from this condition is insulting and unacceptable.
Condition 12 requires a tide gauge to be approved by the County and main-
twined by BIMID "or other county-approved agency, or if necessary a Homeowner's
Association." It .is not clear what use a tide gauge will be in an era of rising
sea level; however the County should not seek to impose the burden of its main-
tenance on BIMID without providing for compensation. Coordination with the De-
partment of Water Resources is likewise delegated to BIMID "or other county-
approved agency." With all due respect, the job is BIMID's and the only issue is
that BIMID be compensated for its efforts with respect to Delta Coves.
To the extent that condition 12 seeks to mitigate the hazard from subsi-
dence, two comments are in order. First, short of quickly and massively raising
.the levees or evacuating the Island, this hazard cannot be mitigated, once con-
ditions causing subsidence have been created. Second, monitoring subsidence and
recommending in the future how to mitigate it are not mitigations as the term is
defined in the CEQA Guidelines. Guidelines sec. 15070(b)(1); 15370; Sundstrcm v.
Cozmty of Mendocino 88 C.D.O.S. 4296, 4298, June 22, 1988.
Condition 13 again seeks to deprive BIMID of the opportunity to look after
its own levees, delegating to the County the responsibility for geotechnical
field inspection. While condition 13 would provide.for reimbursement of the
County's consulting expenses, and reporting to the County, it does not do so for
BIMID, which has a much greater stake in the matter.
Condition 22 requires a resolution from BIMID, a county-approved agency or
Homeowner's Association indicating BIMID's agreement to accept and maintain the
Delta Coves levees. What does this language mean? Only BIMID can properly pro-
vide a resolution regarding its own intentions with respect to the Delta Coves
levee. The inclusion of the "county-approved agency, or, if necessary, a Home-
owner's Association"in this condition indicates that the County will consent to
the developer forming a Homeowner's Association to maintain the project levee.
This is not acceptable. First, only BIN9D has this authority. Second, a respon-
sibility of this magnitude-- the safety of the 2500 residents of Bethel Island--
should not be delegated to a group of homeowners.
II. THE COUNTY CANNOT FIND THAT THE PROJECT IS CONSISTENT WITH THE
APPLICABLE GII4ERAL PLAN
Under the State Planning Law, land development must be consistent with the
applicable General Plan. In the absence of a legally adequate General Plan,
projects may not be approved.
A. The 1963 Land Use and Circulation Plan and 1973 Opera Space Gonserva-
tion Plan are Out of Date
By its own terms, the 1963 Land Use and Circulation Plan projects
development only through 1985, and stresses the need for ongoing revision.
Its projections are hopelessly out of tune with present-day reality, in
terms of papulation (grossly overstated), office and commercial development
(grossly understated, practically ignored); the San Ramon Valley ("continues
to be in orchards"). The 1963 Plan projects a greater population occupying
less land, thereby overestimating the amount of open space and agricultural
lands that have been preserved, and does.not project office growth ap-
proaching the amount that has occurred.
2
As of 1987 the 1963 plan does not look towards the future, as the law
requires, and provides no basis or guidelines for future development.
Numerous and piecemeal "area" general plan amendments, which may or may
not be consistent with each other, including the "West Pittsburg Area Gene-
ral Plan," do not cure the lack of any overall., county-wide plan as required
by state law.
Likewise, the 1973 Open Space Conservation Plan has expired by its own
terms. This Plan (like the 1974 Scenic Routes Element) also refers to a
needed mid-1970's revision of the General Plan, which has still not been
accomplished.
B. The 1%3 Land Use Plan is Inadequate
The 1963 Land Use Plan does not identify areas in flood plains, solid
waste disposal sites, or utilities and facilities. For standards of popula-
tion . density and building intensity it refers to a summary of the 1963
Zoning Ordinance, which is not contained in the Plan, and which has un-
doubtedly changed since then. The defects with this procedure are too
numerous to mention, aside from the question of whether the substance of the
1963 Zoning Ordinance meets the requirements of state law in 1987.
The Land Use Plan fails to predict, project, or regulate office deve-
lopment, which has become a significant land use in both incorporated and
unincorporated areas of Contra Costa County. It also divides residential
uses into four groups: high, medium and low density single family, and
multiple. The fourth category needs to be more defined, especially with
respect to the instant project.
C. The 1963 Circulation Plan is Inadequate
This Plan does not state how the proposed transportation system is to
be accomplished. It does not list the major roads (it refers to the Tudor
report.), and those it does mention are either no longer in existence or have
been renamed (e.g. "I-40"). In any case, the Circulation Plan is not corre-
lated with existing land uses, especially offices.
D. The "General. Plan" is Internally Inconsistent
1. 1963 Land Use Plan vs. 1963 Circulation Plan
The 1963 Land Use Plan is hopelessly inconsistent with the 1963 Circu-
lation Plan. The Land Use Plan is not explicitly based on any set of projec-
tions other than those presented in it. The 1963 Circulation Plan is based
on a 1959 traffic and circulation study by a consultant named Tudor. Are
these the same projections? It is doubtful, but who knows? There is certain-
ly no way to determine this from the contents of the plans themselves.
2. 1963 Land Use Plan vs. 1984 Housing Element
The 1963 Land Use Plan makes no provision for numerous uses and deve-
lopment techniques called for in the 1984 Housing Element: manufactured
housing, second units, PUDs, condominiums, shared and cooperative housing.
Moreover, the 1963 Plan's projections differ from those upon which the
Housing Element is based, and it makes no projections or provision for
accomodating housing.called for in the Housing Element.
3
III. The EIR is Inadequate with Respect for the Current Proposal and Dust Be
Supplemented and Supplemented and Recirculated
CBQA (Pub.Res. Code sec. 21000 et seq. ) requires that agencies disclose and
consider the full scope of the significant environmental impacts of their ac-
tions, before they act. Thus, when an EIR no longer fully discloses a project's
impacts, it must be supplemented, or a new EIR must be prepared.
CEQA and its implementing Guidelines (14 Cal.Adnin.Code sec. 15000 et seq. )
specify three types of occurrences which might render an existing, otherwise
adequate EIR, inadequate:
1. there are "substantial" changes in the project which will require "major
revisions"- of the EIR (Pub.Res.Code sec. 21166(a)),
2. "substantial" changes occur with respect to the circumstances under
which the project is being undertaken which will require "major revisions"
of the EIR (Pub. Res. Code 21166(b)), or
3. new information which was not known and could not have been known. at the
time the EIR was certified, becomes available (Pub. Res. Code 21166(c); see
also Guidelines sec. 15162).
Numerous cases evaluating project changes under section 21166 have directed
that new EIRs be prepared. Concerned Citizens of Costa Mesa v. 32nd District
Agricultural Association (1986) 42 Cal.3d 929 (changes to a stadium-- increasing
seating frau 5000 to 7000 seats, enlarging the site frau six to ten acres, and
reorienting the sound stage -- necessitated a subsequent EIR); Mira Monte Rome-
owners v. San Buenaventura County (1985) 165 Cal.App.3d 357 (after preparation
of an EIR but prior to apprdval of the project, it was discovered that the pro-
ject would encroach on an additional one-quarter acre of wetlands beyond that
assumed in the EIR; despite the fact that mitigation measures for this encroach-
ment were prepared and adopted, the County's failure to prepare a subsequent
environmental analysis was held to be a violation of CEQA); City of San Jose v.
Great Oaks Water Co. (1987) 192 Ca1.App.3d.1005 (a change substituting the City
for the water company as a water service provider in a subarea of the city was
held to be a significant change requiring a revised EIR, since that change would
result in the drilling of different wells with different environmental impacts);
Iwaain Harte Homeowners v. County of Tuolumne (1982) 138 Cal.App.3d 233 (deletion
from a general plan of a prohibition on heavy industrial development, and a
limitation in seismic safety requirements, were each found to be significant
changes requiring EIR supplementation).
In contrast, in Bowman v. City of Petaluma (1986) 185 Cal.App.3d 1065, a
subdivision development was approved with access through a small residential
street ("B" Street); the access was changed to an arterial street ("D" Street).
Later, a tentative subdivision map was approved which showed "D" Street as the
only access. In connection with this "change" in the project, the City prepared
a subsequent traffic study as an addendum to the prior EIR (pursuant to Guide-
lines sec. 15164), held public hearings on the addendum, and responded to public
comments. The court upheld the City's conclusions, as supported by substantial
evidence, that the use of "D" Street instead of "B" Street would cause no sub-
stantial increase in the traffic impacts of the project, and indeed that it
would cause a reduction in traffic impacts. No subsequent EIR, was found neces-
sary. Bowman, supra, at 1077-78.
Section 21166 and Guidelines section 15162 are silent as to the procedure
to be used to make the required determinations. However, consistent with the
fundamental public information purpose of CEQA, whatever procedure is used must
be open and public. At least an Initial Study is required. The public partici-
4
d II
l
patian requirement was reaffirmed in City of San Jose v. Great Oaks Water Co.,
supra, 192 Cal.App.3d at 1017:
"We conclude that the City violated CBQA by failing to make a deter-
minaticn whether a subsequent or supplemental EIR was required by the re-
design of the project, or whether an addendum to the final EIR would suf-
fice. There should have been an opportunity for public heariss and oamm-
ments prior to this determination. Id., emphasis added.
The Great Oaks court held that a detenvd nation under Section 21166 may be
made only after "an opportunity for public hearings and comments," and that
failure to do so was a prejudicial abuse of discretion. Id. at 1017.
A. The County's Failure to Recirculate the 1976 EIR
It has not been possible to obtain complete information about the project
from the County. The EIR was not available from the Clerk of the Board of Super-
visors, as was stated in the published notice, and copies that were finally `
obtained from the Planning Department were incomplete and had to be supple-
mented. In short, because there has been no preparation of an updated. Initial
Study and no description of the project as it is in 1988, we can only assume
that the project (except. as amended by the conditions of approval) is the same
as it was in 1976.
At the very least, a new Initial Study must be prepared, to enable the
public to convent on whether the 1976 EIR is still adequate.
S. The Necessity for a New EIR {
On June 21, 1976 the County released its responses to comments on the draft
EIR for the Delta Coves project. On September 21, 1976 the Board of Supervisors
certified it for purposes of the rezoning and preliminary development plan.
Before the Board may certify the EIR and approve Delta Coves, it must an-
swer the three questions required by Section 21166: Have there been "substan-
tial" changes in the project which will require "major revisions" of the EIR
since 1976? Have "substantial" changes occurred with respect to the circum-
stances under which the project is being undertaken which will require "major
revisions" of the EIR? Has new information which was not known and could not
have been known at the time the EIR was certified, became available?
A fair look at the world in 1988, as opposed to 1976, compels an affirma-
tive answer to all three.
1. Manges in the Project
It has been impossible to obtain adequate information about the project as
its now, because the County has not circulated any current information about it.
Thus, we must assume that the project is the same as it was in 1983 (subject to
new conditions of approval). On the basis of this assmmption, there are two
significant changes in the project: the wildlife preserve islands included in
the original proposal have been eliminated, and the configuration of the lagoon
has been changed so that circulation of the water will rely on tidal action
instead of pumping.
Elimination of the wildlife islands will have the obvious effect of elimin-
ating wildlife. Reliance on tidal flows for flushing the lagoon will cause
changes in water quality, and therefore potentially aquatic life, as well as the
quality of life for humans in surrounding parts of Bethel Island. All of these
5
y
impacts need to be examined.
2. Changes in Circumstances
Since the original approval of this project in 1976 the County has adapted
the East County Area General Plan, and has undertaken a planning process not
only for Bethel Island (the Bethel Island Specific Plan), but also-- for the
first time since 1963-- for the County as a whole.
Changes in circumstances include unexpected and unplanned growth which
increased demands for virtually every public service (fire, police, schools,
etc. ) and every type of infrastructure (water; sewer, roads, etc. ). One example
of the extent to which ythe County has still been unable to come to grips with
these problems is the successful lawsuit challenging the adoption of the Oakley
General Plan Amendment, which relates to an area which will be substantially
affected by growth on Bethel Island. Even when it prepared a current EIR, the
County was unable to adequately deal with the impacts of growth in that area.
The Delta Coves 1976 EIR did not even attempt to do that. Its analysis of the
impacts of the delta Caves project on the east County area generally, and the
nearby area in particular is altogether inadequate.
A brief review of the documents listed in Appendix A, all prepared by the
County and all hereby incorporated by reference, will show just has deficient
the Delta Coves EIR is today, twelve years after it was prepared.
One particular aspect of this deficiency is that the EIR does not contain
an alternative which is designed to be consistent with existing (or proposed)
plans in 1988. What does the Bethel Island Specific Plan indicate for this pro-
perty? What does the proposed Growth management Program say? What do the draft
General Plan Policies say? Both the County as a whole and Bethel Island are
undergoing major General Plan reviews. Any adequate and up to date EIR must take
these into account.
3. New Informatim
Substantial new information has cone to light since the 1976 EIR which
bears directly on this project. Sane of this new information is referenced as
Exhibits E, F, and H-J in the staff report, but has not been publicized, circu-
lated for public comment, or treated as it should have been to cooly with
CEQA•
Since 1976 new information has been developed with regard to land subsi-
dence due to dewatering and gas drilling, and a comprehensive study of this
phenomenon has just begun. The Delta Coves project will require substantial
dewatering in order to construct the new levees. New information related to the
existing conditions in the East County area as a result of the last ten years of
growth has also been developed (see Appendix A), which bears directly on the
impacts of this project. Finally, the last ten years have seen the scientific
conminity accept the inevitability of the greenhouse effect and the consequent
rise in sea level. Indeed, the last few years have seen these phenomena deman-
. strated. The effects of a rise in sea level in the range of four feet (the mid-
level prediction) on a project such a Delta Coves is obvious. It requires oon-
sideration.
6
IV. CONCLUSION
The Bethel Island Municipal Improvement District urges the Board not to
certify the 1976 Delta Coves BIR, and not to approve the project as proposed.
Approval would subject the residents of Bethel Island to the risk of catas-
trophic flooding, would place BIMID at risk for the damages resulting from such
flooding, and would begin the spiral of ever increasing levee maintenance costs
for Bethel Island levees.
In short, there is no legitimate reason to approve this project, and every
reason to deny it.
Very truly Yours.
Zach Cowan
District Counsel
7
d
a '
APPENDIX A
East County Area General Plan, adopted April 1978
Growth Trends, 1st ed., November 1985
Summary of Agency Plans and Programs, May 1986
Summary of City and County General Plans, November 1986
Growth Trends, 2nd ed., July 1987
Draft General Plan Policies, December 1987
General Plan Review Growth Management Program, April 1988
8
• N�T. DIABLO AUDUBON SOCIETY
l.Oi�TR� �ujFR.Q ; * S3
Ns �h ': z�IFORNIA 94597
8$�U�i -
00141 ful:!TY D_;IELM 14T DEPT.
\ June 29. 1988
" EREOC 3QED
19R8Honorable Robert Schroder .-
uAT(�Chair, Board of Supervisors aoocsu VISORS
Contra Costa Count RACnS*A.COy L� Deputy
P. 0. Box 961
Martinez, California 94553
Re: Delta Coves Project - Request 'or ::oars to Re-iect Project Proposal
va
Dear Chairperson Schrcder and Members of the koard:
The Mt. Diablo Audubon Society wishes to state for the record it's
opposition to the .proposed Delta Coves Froiect ana encourages the Boara to
stay the course on rejecting any heavy nanaeo ettort5 at a legal
settlement that will compromise public health ani . aiety, good planning
and common sense.
This letter is not intended as a detailed analysis of the proposed project
or it's legal history. Instead we would like to highlite certain factors
which make this a bad project regardless of legal procedu s. Theses
r factors are.
Filling of 'valuable'vetlands. We will not try ad We f
lands at one end of the County from Oil Spills, while wetlands at the
other end are filled to build houses. If a project is to be built at
this site, it should be a project designed to not fill wetlands.
2. Breach of Island levees. The General Plan Congress has proposea
a policy that calls for no breaching of existing levees in the East
County area. This project wouia to inconsistent with the proposed
poli=ies of the new General Ilan.
3. Water Quality Issues. One should only look at this mornings
paper concerning the large fish Bill at Discovery Bay .last veek to
understand this concern. The proposed project will not provide adequate
water treatment to assure high quality water in and around the project.
With plans to increase water for arinking from the Delta we can not accept
Exhibit F
P 'R -2- :.y. .
pollution of those raters from poorly -planned projects such as this one.
.
4. Earthquake/Liquefaction threats to all people living on the
Island. Again check out the morning paper. The County geologist has
informed the General Plan Congress that levee failures due to earthquakes
�,- away from the Delta are a possibility. With old levees, rising ocean
levels from the greenhouse affect and liquefaction possibilities .from the
Island soils, this project could threaten public health and safety.
FAILURE TO DISCUSS A LESS ENVIRONMENTALLY DAMAGING ALTERNATIVE
The review of alternatives goes to the core of CEQA. The legislature and
the courts have repeatedly affirmed the need to discuss alternatives to
e proposed project. Particularly alternatives that reasonably meet the
goals of a proposed project but reduce the significant impacts of a
proposed action.
We believe the project applicant has failed to do this and want to see
an alternative that allows some development without breaching levees and
filling wetlands.
CONCLUSION
Clearly good growth in this county requires good planning. Good planning
must start with a ,fair and informed assessment of new growth imDacts to
the local and regional environment, be it wetlands or schools. .uch good
planning, particularly at the regional level is the principal respon- '
sibility ' of County government. Many of the problems we face to;ay are a
direct result of the failure to plan for regional growth impacts.
The Board of Supervisors has recently indicated that the ways of the
past were changing. That a new general plan would address growth manage-
went issues. Unfortunately this project in its present condition
reflects business as usual. If approved as presented, the inadequate
nature of the information and analysis contained in the EIR vill,°allow.,..-";—
urban development with no plans for adequately reducing ,,growth. apacts
4 » t the :environment and .improving the. quality of i fe.for a cit ,off .
C+ost_s Count andg articularly £ast Counfy �`
�s
f { _ x `atterand:our concern about .the inadequate review of the proposed
faction are not intended to stop or slot growth. They are intended to
=wove the Board and the Staff towards a better assessment of the sig-
nificant. impacts for the East County Region .resulting from this project,
so that mitigation of these impacts can be formulated and implemented.
Please reject this proposal.
Sincerely,
1A.
L)it
Litv,,C+t��
30
to ll�
At-1 3 i
�o
L a
Exhibit G
RAY B. KRONE & ASSOCIATES
SEDIMENTATION TIDAL HYDRAULICS
December 28, 1987
Mr. John Scott .
Attorney at Law
433 Turk Street
San Francisco, CA 94102
Subject: Delta Coves Project _ Circulation of Project Waters.
Dear Mr. Scott:
The report, "Investigation .of Tidal Flooding in the Proposed Woodlanding
Development," presented our findings that the maximum average retention time
of the lagoon waters without augmentation to tidal flushing would be 35 days.
The water depths of the lagoons will be 17 ft or more at mean tide level. As
presented in that report, the average residence time in a similar deep lagoon at
Bel Marin Keys, Marin County, is 90 days, and there have been no algae problems
in the lagoon during the 20 years that this retention time has prevailed.
The maximum concentration of algae that could be expected in a summer
bloom was calculated using the following conditions: There are excess nutrients,
no sedimentation of algae occurs, the water temperature is 20 degrees Celsius
throughout the depth, the suspended solids concentration is 20 mg/1, the
detention time is 35 days, and the concentration of chlorophyll-a in slough waters
is 6 micrograms/liter. The calculation resulted, in a maximum chlorophyll-a
concentration of 92 micrograms/liter. This concentration would make the
waters green, but should not be an aesthetic nuisance.
If augmentation of the circulation is desired to reduce the concentration of
algae, the augmenting water should be pumped from a slough distant from the
lagoon rntrance to minimize recirculation of the lagoon waters, and the discharge
should be at the ends of the lagoon arms as shown in the referenced report.
Sincerely,
KGe
Zy
B. Krone
Exhibit H
P.O. BOX 694 DAVIS, C 95617 TELEPHONE (916) 753-2555/7521435
i
Proceedings of the Trilateral Seminar-Workshop on
Lifeline Earthquake Engineering
• Taipei. Taiwan, November 1985
RUPTURE OF EMBANKMENT DAM DUE TO FAULT MOVEMENT
C.K. Shen (I)
James A. Cheney (I)
Joonik Sohn (II)
SUMMARY
A centrifuge model study on the response of homogeneous embankment dam to
fault movement has been reported. Preliminary model test results have indi-
cated that two different types of failure in the soil can be identified with
the crack pattern. A tension failure near the surface and a shear failure
deep in the embankment. The rupture surfaces were neither continuous trans-
versely nor open deep in the embankment, thus no leakage of water was
observed. Under the conditions prescribed by the physical dimensions and
boundaries of the models, it appears that catastrophic failure and emptying of
reservoir water is not likely an immediate threat to embankment dams subjec-
ted to sudden fault movement.
INTRODUCTION
Since potable water is one of the most precious and limited resources on
earth, the effective use of it to assure a reliable and continuous supply is
an important and crucial "Consideration for the, welfare of mankind. In many
areas of the world, surface water is collected in reservoirs formed by dams.
The stored water is then delivered for agricultural, industrial and domestic
uses through a properly designed distribution system. At the head of the water `
distribution network is the dam-reservoir unit which is located upstream from !
its service areas. If. the water in the reservoir were suddenly released as a
result of breakage or failure of the dam, damages to the downstream areas
could be devastating. Therefore, the dam-reservoir unit should be thoroughly
investigated and assessed, and integrated into the overall lifeline engineer-
ing plan to combat possible natural disasters.
1
Seismic stability of embankment dams has. been studied extensively in the
past decade or two. Mainly two major causes of dam instability have been
identified: the failure of embankment slopes due to earthquake loadings, and
the excessive embankment deformation and/or crest settlement resulting from
the seismic mobility and liquefaction of embankment as well as foundation
soils. However, the potential damage of dam breakage has not been adequately
addressed. Fault displacement of large magnitudes can cause sudden surface
rupture of a few feet to tens of feet. If a dam is located across an active
fault, the potential of dam breakage cannot be overlooked. Table l .is a par-
tial list, compiled by Bennett (1), of embankment dams in California located
on active faults. Some of them are situated, precariously above densely popu-
lated areas. Should a dam failure due to fault movement, the consequences of
potential damage are indeed awesome.
(I) Professor, Department of Civil Engineering, Univ. of Calif. Davis.
(II) Graduate Student, Department of Civil Engineering, Univ. of Calif. Davis.
- 355 -
To date, the dam breakage aspect of dam design is largely empirical,
stressing the importance of a proper choice of design details such as a tran-
sition zone, to ensure safety against rupture or breakage (3). Due to the
fact that there have been scanty record of failure or major damages caused by
displacement of faults during earthquakes, and that small scale bench model
tests are not suitable for geotechnical structure, there has been very little
useful information upon which a rational method of assessment can be for-
mulated.
Small scale laboratory models are severely limited in their applicability
to the prediction of behavior of full scale geotechnical structures, because
when gravity is the principal loading agent, the state of stress in a small
scale model loaded by its own weight is much smaller in magnitude than in the
corresponding full scale prototype. This difference in stress states gives
model behavior that is quite different from that of the prototype because soil
properties are stress dependent. However, if the model is placed in a centri-
fuge, and subjected to' centripetal acceleration the state of stress at every
point in the model can be made the same as at the homologous point in the pro-
totype, thus eliminating major deficiency in model testing of geotechnical
structures.
In light of the increasing popularity and availability of centrifuges for
modeling of geotechnical structures, a preliminary centrifuge model study to
investigate the damage and rupture of a homogeneous embankment dam owing to
strike-slip fault movements directly beneath the dam was carried out and
reported by the authors (2). It was observed that the crest displacement can
be related to the fault movement, and different failure patterns may be iden-
tified that depend upon the length to height ratio of a dam. The tests were
conducted with an empty reservoir, the problems of water leakage and soil ero-
sion after fault distortion were not considered. Since then additional tests
have been performed that includes a water reservoir on the upstream side of
the dam. The results of this study; are reported herewith.
CENTRIFUGE MODELING AND THE TESTING PROGRAM
The centrifuge available at Davis is a one-meter radius Schaevitz (B-8-D
rotary accelerator) capable of operating at a capacity of 10,000 g-lbs (e.g.
100 lbs at 100 g's). The dimensions of the bottom of the swing platform are
18" by 18". Thus the size of the embankment model that can fit the platform
is limited. Because of the small size of the platform and the limited g-load -
capacity, models built for this study are simple, homogeneously compacted clay
models.
The building of models follows essentially the same procedure as described
in Ref. (2), however, a specially designed rubber 110" ring seal is installed
along the fault line to prevent the leakage of water impounded in the reser-
voir through the fault itself. Briefly, the model box is made of aluminum;
inside, there are two halves of the model base rock and the adjacent abutment
on either side of the fault line. One side of the base rock and -abutment is
fixed to the box; however, the other side can slide simulating a simple
strike-slip fault movement. An air piston positioned below the model drives
the sliding block. The piston is connected to a high pressure (600 psi) cyl-
inder which is mounted on the centrifuge arm near the center of rotation. The
movement of the piston can be adjusted to produce a horizontal displacement of
the sliding block 'in the range of 0.1" to 1.0". This movement is applied sud-
- 356 -
r
denly under the control of an electrically triggered solenoid valve. Figure 1
shows a photograph of the model box. The surfaces of the basement rock and
abutment blocks are covered with glued coarse sand to insure that adequate
frictional capacity can be developed at the dam-foundation interface.
Model dams are built of compacted Yolo loam, a locally available silty-
clay soil. The placement .?ter content is approximately 20% and the dry den-
sity is about 107 lb/ft . The embankment is compacted in lifts of
approximately 0.9" thick. The compaction effort, using a 5.5* proctor compac-
tion hammer, is predetermined for each layer to insure a homogeneously com-
pacted dam. The standard AASHTO compaction curve of the material is shown in
Figure 2. All compacted models are cured in the moisture room overnight prior
to testing. The dams are built to simulate a 17 ft. high prototype dam. The
upstream and downstream slopes are 1:2 and 1:1.75 respectively. The base of
the full scale dam is 67.5 ft wide, placed directly on the basement rock. The
one sixtienth scale models are tested under an artificial g-level of 60. The
dimensions of the corresponding cross sections between the prototype and the
model are given in Table 2. White paint lines parallel to the crest are drawn
on both the downstream and upstream faces of the dam; a line of white-head
pins are also placed along the crest of the dam. These markers give a visual
display of the movement of the dam for still photos and T.V. viewing while
testing is in progress. Water is filled in the upstream reservoir to the ele-
vation of 15 ft. The total free board is 0.4" (2.0 ft - prototype). A trans-
parent plastic strip (shield) is placed along the length of the crest to
prevent the spilling of water over the crest resulting from seiching in the
reservoir, a phenomenon noticed as the model accelerated toward the desired g-
level. Figure 3 shows a model dam ready to be tested.
To start the test, the model is first brought to the proper g-level (60
g's 236 rmp) under which the basement rock displacement is to be applied. The
model is then kept at that g-level for 15 minutes to establish the equilibrium
stress state and the steady state hydraulic flow condition through the earth
dam. The centrifuge is then stopped for inspection of the reservoir water
level and other possible abnormalities. After a careful check over the model,
it is again brought up to the 60 g's gravity field and kept at that state for
5 minutes to re-establish the equilibrium conditions. A sudden horizontal
displacement of known quantity is then applied to the sliding block. Looking
upstream, the right half of the block is moved upstream with respect to the
left half. Crack patterns appear immediately. in the dam. The test, however
is continued for another 15 minutes to observe if abnormal water leakage
and/or instability of the dam would follow. A typical crack pattern is shown
in Figure 4.
RESULTS AND DISCUSSION
A total of 5 models were tested. They were of identical cross-sections
subjected to different amounts of displacement ranging approximately from 0.1"
to 0.611, which translated to be 0.5 ft to 3 ft of prototype fault movements.
The crack pattern of each model was carefully observed, photographed and docu-
mented. The crack patterns of all 5 models were very similar, the extent of
pattern development, however, varied with different amounts of fault movement.
Based upon visual observation a typical crack pattern is constructed as shown
in Figure 5. The dam, atter experiencing a sudden fault movement, broke into
3 major blocks; however, the cracks were such that the did not run directly
from upstream to downstream thus. causing no leakage of water. The pattern was
observed in all of the models. As noted before, an additional 15 minutes of
spinning at 60 g-level was maintained to observe if secondary failure or water
leakage would follow the sudden breakage of the embankment. None was
detected.
After a careful examination of the deformed models, a number of interest-
ing features are listed below:
1. The surface cracks appear mainly in the upstream part of the moving
half (the right side) and the downstream .part of the fixed half (the
left side).
2. Major cracks start at the toe of the embankment next to the fault
line.
3. The major crack curves toward the abutment ,wall as it travels upward
along the embankment. The surfaces on both sides of the fault line
bear almost identical crack patterns.
4. No noticeable major cracks at the crest level are observed, however,
the crest line is distorted. Small cracks are present when larger
fault movements are applied.
5. The major cracks on? the surface of the embankments are open, tensile
cracks; however, they disappear at greater depths and do not continue
to the bottom.
6. No evidence of delayed slope failure of the embankment results with
fault movement.
7. One of the two internal rupture surfaces separating the dam into
three major blocks is sketched as shown in Figure 6. The surface on
the central (major) block is curved, dipping downward toward the
fault line.
The above description, though only applicable to a specific prototype
embankment dam simulated by the models, testifies to a very important use of f
centrifuge modeling of geotechnical structures; namely the observation of pos-
sible failure mechanism(s) of structures being. studied. Such information can _
be of great help in developing rational engineering design and can give
insight to formulating realistic solutions. On that basis, we shall further
examine the model response and offer explanations for the observed behavior.
The most interesting observation is the fact that although a significant
fault movement at the base of the dam can cause failure of an embankment dam,
the cracks developed in the dam do not impose an immediate threat of leakage
of water thus it is not likely to cause a collapse of the dam due to piping or
erosion after the base rupture. It is also important to note that although
open cracks are present on the surface of the embankments, they do not appear
to penetrate deeply into the interior of the dam. In any event, the dam is
badly distorted and probably should be replaced. . Emergency steps should be
taken to empty the reservoir in order to alleviate any possible long term and
short term danger, however the test results indicate that the dam should hold
water while this is being done.
- 358 -
The cracks are caused by failure of the embankment soil due to the sudden
displacement along the fault line. From. the pattern of the crack development,'
it seems to indicate that there are two different types of failure in the soil
that can be identified with the crack pattern: first, the strike-slip fault
movement cutting right across the axis of the dam can be viewed as if the dam
was being sheared essentially in a simple shear state as shown in Figure 7.
Under this condition, soil in zones (I) and (III) are .subjected to tension and
in zones (II) and (IV) are subjected to compression. Second, the soil near
the vicinity of the fault zone is subjected to a large fault displacement and
the soil fails in shear. The shear failure plane at the base .of the dam
should be continuous across the entire width of the dam; however, being a
shear failure, it does not open. Furthermore, due to the relatively wet and
plastic nature of the clay and_ the heavy overburden, this rupture plane deep
inside the dam tends to heal by itself, thus prohibiting the flow of water
through the failure plane. The orientation of the failure plane changes as it
moves upward in the interior of the dam since the overburden pressure, the
lateral and shear stresses are different at different locations. As the fail-
ure plane moves further upward in the embankment soil, the magnitude of the
shear induced tensile stress may exceed the corresponding compressive stress,
thus tensile failure with crack opening may take place. The direction of the
tension crack in the soil is dependent upon the stress state acting on the
soil; the smaller the compressive stress, the more likely that the tension
crack will be aligned at 45o with the direction of shear displacement. This
explains the crack pattern ,shown on the surface of the embankment: e.g. an
open crack ost the upper level of the embankment running at a direction approx-
imately 45 with the transverse axis, and gradually turning into a closed,
vertical crack near the toe. There is of course also an invisible shear. zone
at the base of the dam which cannot be identified easily.
The above illustration gives a rational and mechanistic interpretation of
the model test results and in the writers opinion greatly enhances ones.under-
standing of the interaction and response of a dam-foundation system due to a
fault movement.
SUMMARY AND CONCLUSION
A centrifuge model study on the response of embankment dam to fault move-
ment has been reported. The crack patterns were carefully examined and
interpreted. The model test results have indicated that the rupture surfaces
in the embankment dam were neither continuous transversely nor open deep in
the embankment, thus no leakage of water was observed. Under the conditions
prescribed by the physical dimensions and boundaries of the models, it appears
that catastrophic failure and emptying of reservoir water is not likely an
immediate threat to embankment dams subjected to sudden fault movement.
However, it is important to point out and must be stated clearly that the
results and conclusions derived from this study apply only to the models
studied. The model is a simple one; a variety of important parameters have
been left out from this study, therefore the results should not be generalized
to reflect the responses of different types of dams under different con-
ditions. Nevertheless, the study does bring up the focus of an important
problem which has long been neglected in our pursuit of the overall safety and
reliability of water supply and distribution systems in lifeline earthquake
engineering. It has given us the opportunity to SEE a failure that can guide
our thinking in conceiving a relevant approach to solve this problem. For
instance, it is evident that the long considered conventional wisdom of widen-
359 -
ing the transition zone as a general guideline to improve the safety of an
embankment dam against fault movement may not be effective. Conceptually,
this study guides us to identify possible important factors which may have
significant bearings on the response of the dam a.-id the subsequent breakage
potential during fault movement. Some of these are briefly discussed as
follows:
1. Obviously, the shape (broad or narrow valley), the type (zoned or
homogeneous) , the height (with respect to the length and width) of the dam
will affect the crack pattern development.
2. The direction of fault movement with respect to the axis of the dam can
significantly influence the distribution of cracks. It is possible for
the case of a homogeneous embankment dam to have continuous tension cracks
running transversely through the dam if the direction of fault is skew
with the axis of the dam (Figure 81.
3. The importance of the free board or water level in the reservoir should be
carefully evaluated in accordance with the magnitude of fault movement,
dam height, the extent of tension zones, etc.
4. Consideration should be given to the possible use of geotextile or
geogrid to strengthen the dam at higher elevations for the purpose of pre-
venting tensile failure or the development of tension cracks.
Indeed, the problem of dam breakage due to fault movement is a very com-
plex one. A rational solution to this problem is still far from reality.
.However, a general picture of the dam-foundation interaction behavior model
has been identified from the results of the simple centrifuge model tests. We
believe additional work including larger models tested in large centrifuge and
numerical simulation using 31D finite element solutions should be attempted
toward a practical solution.
ACKNOWLEDGEMENTS
The researsch presented is supported by the National Science Foundation
under Grant No. CEE-8211471. The authors are grateful for this support.
REFERENCES
1. Bennett, W.J. , Private Communication, California Department of Water
Resources.
2. Cheney, J.A. , Shen, C.K. and Ghorayeb, F. , "Fault Movement: Its Potential
Damage to Embankment Dams," Proceedings of The 8th World Conference on
Earthquake Engineering, Vol. III, San Franciscp, August, 1984.
3. Sherard, J.L. , Cluff, L.S. and Allen, C.R., "Potentially Active Faults in
Dam Foundations," Geotechnique, Vol. XXIX, No. 3, September, 1974.
-
360- -
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MODEL AND PROTOTYPE DIMENSIONS
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(ft) (in)
H 17.0 3.40
b 3.75 0.75
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m 36.25 7.25
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- 362 -
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- 366 -
Figure 6. RUPTURE SURFACE IN THE DAM
- 367 -
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- 369
RAY S. KRONE & ASSOCIATES
SEDIMENTATION TIDAL HYDRAULICS
December 28, 1987
Mr. John Scott
Attorney at Law
433 Turk Street
San Francisco, CA 94102
Subject: Delta Coves Project _ Flooding of the Bethel Island "Corridor."
Dear Mr. Scott:
This letter was prepared in response to your request for an evaluation of a
hazard to the residents of Bethel Island resulting from the construction of the
Delta Coves project. The concern that you described is the danger of a "wall of
water" that might travel down the corridor formed by the Delta Coves levee and
the levees along Dutch and Sandmound Sloughs in the event of a levee failure.
This corridor would be about 500 ft wide at the west end and would gradually
taper to a width of about 250 ft at the east end. Preparation of this letter
included examination of the current plans for the. Delta Coves development, an
aerial tour of the Bethel Island levees, conversations with Mr. Howard Holms,
Director of the Bethel Island Improvement District, and other references.
Mr. Holms described the conditions of the existing levees as "the best in the
Delta." He reported that the 11.5 miles of levee around Bethel Island are
constructed with imported soil and the levee rests on good foundation material.
The levees are designed for floods with a 500 year recurrence interval, and
slopes range from 2:1 to 3:1. No boils have been observed on the island side of
the levees in recent years. Mr. Holms' main concern was for subsidence due to
extraction of gas in the area. Surface elevation profiles were measured in 1979,
and another determination is in progress. The district appears to be well
managed. The aerial tour supported Mr. Holms' assessment. The appearance of
the levees shows them to be well cared for.
The plans for the Delta Coves development show perimeter levees that are
135 ft wide across the top with side slopes of 1.7:1. The water side of the levee
is to be protected against wave erosion by rip-rap. If these levees are
constructed with the supervision of a geotechnical firm, they should also be
sound.
The character and velocity of a flood wave depend on the character of the
levee break and the geometry of the flooded area. The development of a "wall of
water" in the corridor would require sudden removal of a length of levee
comparable to the width of the corridor. Earthern levees do not fail in this
mode: levee failures' are initiated by overtopping or flow through .an animal
burrough. In eitner case, the failure enlarges itself by erosion of the levee, and
Exhibit I
P.O. BOX 694 'MAVIS, CA 95617 TELEPHONE .(916) 753-2555/752.1435
the result is a rapidly but not catastrophically increasing flow. Residents of the .
flooded area experience first the intrusion of shallow water, then gradually rising
water levels. Currents would be highest near the break and diminish to low
velocities at the most distant areas. The rate of rise would depend on the rate
at which the levee opening enlarged and on the flooded land area. Construction
of the project would reduce the flooded land area, and the rate of rise of flood
waters for a given break scenario would increase in inverse proportion to the
reduced area. The rise would still be gradual. There would be no "wall of
water" propagated down the corridor.
There is always the possibility of failure due to earthquake. Recent studies
show that failure of earth structures due to earthquakes, is not catastrophic,
however. A paper reporting a study of the response of a homogeneous embank-
ment dam to earthquake fault movement is attached.
I am not aware of any catastrophic failure of a levee that could cause a "wall
of water" in the Delta during the history of Delta levees.
Flooding is a tragic event even without the impact of a "wall of water," and
this letter in no way diminishes the importance of maintaining the levees at
Bethel Island or of constructing sound levees in the project. The condition of
the present levee system and the design of the planned .development are
assurances that prudent precautions against flooding are being taken.
Sincerely,
Zy B. Krone
Delta Coves
12-28-87 Page 2
RECEIVED
MAY i-7 1988
PROFESSIONAL RECORD
OF PHIL I TCHEL R
qK RO OF SU RVISORS
CO A COST
sy Deputy
RAY B. KRONE
I. PERSONAL DATA
1. Born: 1922, California
2. Education:
B.S. in Soil Science, 1950, University of California, Berkeley
M.S. in Sanitary Engineering, 1958, University of California, Berkeley
Ph.D. in Sanitary Engineering, 1962, University of California, Berkeley
3. Professional Affiliations:
a. Member, American Society of Civil Engineers
b. Member, American Association for the Advancement of Science
c. Member, American Geophysical Union
d. Member, California Water Pollution Control Association and the
Water Pollution Control Federation
e. Member, Sigma Xi, Chi Epsilon, Tau Beta Pi
f. Member, San Francisco Bay & Estuarine Association
g. Associate Editor, Estuarine & Coastal Marine Science, Academic
Press
4. Research and Publications: (See attached list)
2/l/84
Exhibit J
u
Ray B. Krone
Page 2
IL EXPERIENCE RECORD
1. Professor, Civil Engineering, Department of Civil Engineering, University
of California, Davis, 1970 to present,. Associate Professor, 1964-70.
2. Chairman, Department of Civil Engineering, University of California,
Davis, July 1968 to July 1972.
3. Associate Dean for Research, College of Engineering, University of
California, Davis, duly 1972 to present.
4. Consultant, Waterways Experiment Station, U.S. Army Corps of
Engineers, 1960 to present. Services include design, training and
interpretation for radioactive tracing and other measurements of sandy
and cohesive sediment transportation, studies of the origins of waste
deposits, and participation in training programs, panels, and committee
meetings on sediment transport and water quality of estuaries. These
services are provided for a number of district and division offices
throughout the United States and for the U.S. Office of the Attorney
General.
5. Member, Board of Consultants on Delaware Estuary, Investigation,
Philadelphia District, U.S.A.C.E., May 1968 to 1973.
6. Consultant to Attorney General's Office, State of California, 1969 to
present, charged with determination of last natural low water boundaries
along margins of South San Francisco . Bay and reconstruction of
hydraulics of streams.
7. Consultant to Water Resources Engineers, Lafayette, California, 1966
to 1976, on studies involving estuary and ocean sediment transportation
including estuary development and. water quality, and on groundwater
quality.
8. Consulting services have been and are provided on aspects of estuarial
sediment transportation and water quality to the following partial list
of clients on request:
a. Earl and Wright Consulting Engineers, Inc., San Francisco,
California. Located and oriented supertanker wharf in San Pablo
for minimum shoaling. Designed approach and mooring excavation.
Designed modifications to Martinez Marina to reduce shoaling.
Designed protection wall for Noyo Harbor, California.
b. Bissell and Karn, Consulting Civil Engineers, San Leandro,
California, for the Bay Conservation and Development Commission,
reclamation of gravel pits.
Ray B. Krone
Page 3
c. Esso Research and Engineering, Exxon Refinery, and Benicia Port
Terminal Co., Benicia, California. Designed and tested in the U.S.
Army Corps of Engineers Bay Model an industrial harbor for Benicia.
Designed modifications to existing facilities to reduce shoaling
rates. Assisted in permit applications for dredging.
d.. Skidmore, Owings, and Merrill, and Oceanic Industries, San
Francisco, California. Bay water quality and sediment studies for
Ferryport Plaza project.
e. Sohn Blume and Associates, San Francisco, California. Designed
gate size and operating schedule for scouring the entrance channel
to Bel Marin Keys, Novato.
f. Dames and Moore, Soil Engineers, San Francisco, and Los Angeles,
California. Evaluated proposed dredge spoil transfer station in San
Pablo Bay, assisted design of dredging and filling project in Los
Angeles Harbor for minimum impact on water quality.
g. International Engineering Co., San Francisco, California.
Preliminary design of land disposal of dredge spoil for U.S. Navy
installations in San Francisco Bay.
h. Harding, Lawson, and Associates, San Rafael, California.
Contributed to design of dredge spoil disposal and processing study
for Mare Island Naval Shipyard. Evaluated several small craft
harbor facilities. Evaluated shoaling rates and recommended design
of entrance channel for northern terminal of the Golden Gate Ferry.
i. Federal Water Quality Administration. Prediction of future
suspended sediment inflows to the San Francisco Bay-Delta system.
j. Contra Costa County Water Agency, Martinez, California. Expert
witness at State water rights hearing for California Water Project
diversions (Decision 1379).
k. Moffitt-Nichol Engineers, Long Beach, California. Description of
causes of shoaling in Mare Island Strait and evaluation of remedial
measures, modification of Larkspur channel for wave control.
L City of Vallejo, California. Designed enclosure to minimize shoaling
in Vallejo marina.
m. Santina and Thompson, Engineers, Walnut Creek, California.
Designed entrances and enclosures for proposed municipal marinas
at Pittsburg, Benicia, and Antioch.
r '
Ray B. Krone
Page 4
n. Port of Astoria, Oregon. Evaluated causes of shoaling in port
facilities and recommended alterations.
o. Port of San Francisco. Advised on water quality problems associated
with construction of LASH terminal breakwater.
p. Doug Russell Associates, San Francisco. Designed launching ramp
in Petaluma Creek and assisted in design of wharf" facilities in the
Mississippi River.
q. Latinoconsult, S. A. Determined critical shear stresses of soil and
evaluated testing and analytical program for determining depth of
scour for design of caissons for Brazos-Largo bridge in Argentina.
r. Transbay Constructors, San Francisco, California. Designed dredged
spoil disposal procedures and shore and water quality monitoring
program for material excavated during construction of the BARTD
transbay tube.
s. Evaluated causes of shoaling, recommended remedial measures and
conducted model tests for the Standard Oil Company Richmond
Long Wharf and the Union Oil Company terminal in San Pablo Bay
for these companies.
t. Hallinger Engineers, Oakland. Evaluated shoaling rates for design
of Urich Oil Company wharf at Martinez and at Crockett.
u. Santa Fe - Pomeroy Engineers, Petaluma, California. Evaluated
shoaling rates for proposed designs of Dow ChemicaF Company
wharfs to be constructed at Collinsville.
v. Evaluated and recommended modifications to water-oriented real
estate developments for sedimentation and water quality at Vallejo,
and in the San Joaquin-Sacramento River delta (three projects) and
developed operational program and waterway and control structure
requirements for additional units at Bel Marin Keys, Novato,
California.
w. Designed tidal waterways for marsh restoration for the Golden Gate
Bridge and Highway Transportation District and for the City of
San Mateo. Conducted hydraulic calculations for modification of
Elkhorn Slough and marsh, Moss Landing, California, for the Moss
Landing Harbor District.
x. Consultant and expert witness to Mobile Chemical Co. vs. State
of Florida and Coastal Petroleum on land boundary case (Peace
River boundary) for Holland and Knight (1979-82).
y. Consultant and expert witness on land boundary case on the Lower
Colorado River for Washburn and Kemp.
1 1
` 0
Ray B. Krone
Page 5
Other consulting services provided to Stone and Webster, Boston;
J. B. Gilbert and Associates and VTN, Sacramento; EAE, Palo Alto;
Tudor Engineering, San Francisco; Daniel Mann Johnson and
Mendenhall, Redwood City; California Marine Advisors and
Navigation Committee; Cooper Clark, Redwood City; and many
others.
9. Member of U.S. Public Health Service Review Committee, 1969-70.
10. Consultant to the Environmental Protection Agency Professional
Manpower Training Branch, 1973-75.
11. Consultant, Committee on Tidal Hydraulics, U.S. Army Corps of
Engineers, July 1, 1975 to present.
12. Member, Board of Consultants, U.S.D.I. Bureau of Reclamation, on
prediction of impact of the San Luis Drain on the San Francisco Bay
estuary, 1982 to present.
13. Staff Sanitary Engineer, Sanitary Engineering Research Laboratory,
Associate Research Engineer, SERL and Hydraulic Engineering
Laboratory, and Lecturer, Department of Civil Engineering, University
of California, Berkeley. These were the final positions held in 1964.
Association with research projects in civil engineering began in 1950.
PUBLICATIONS SINCE 1960:
An Underwater Scintillation Detector for Gamma Emitters
A Manual, July 15, 1960
Silt Transport Studies Utilizing Radioisotopes
Third Annual Progress Report, September 1960
Methods for Tracing Estuarial Sediment Transport Processes
Report to Corps of Engineers, U.S. Army, October 1960
Underground Travel of Polluted Water
(with P. H. McGauhey) Presented at the National Water Well Association
Meeting, 1960
Estuarial Sediment Transport Patterns
(with H. A. Einstein) Jour. Hydraul. Div., ASCE, HY2, pp. 51-59, March
1961
Methods of Determining Sand and Silt Movement Along the Coast, and in
Estuaries, and in Maritime Rivers
(with H. A. Einstein) Prepared for XXth International Congress, PIANC,
1961
' r
Ray B. Krone
Page 6
Experiments to Determine Modes of Cohesive Sediment Transport in Salt
Water
(with H. A. Einstein) Presented at 42nd Annual Meeting, A.G.U., 1961.
J. Geophys. Res. 67(4):1451-62, April 1962
Flume Studies on the Transport of Sediments in Estuarial Shoaling Processes
A report to the Corps of Engineers, U.S. Army, June 1962
Modes of Sediment Behavior, and Selection of Harbor Design and Maintenance
Techniques for Minimum Shoaling in Estuaries
Presented at the Coastal Engineeering Conference, Mexico City, 1963
A Study of Rheologic Properties of Estuarial Sediments
A report to the Corps of Engineers, U.S. Army, September 1963
Suspension of Cohesive Sediment by Wind-Generated Waves
(with M. R. Alishahi) A report to the Coastal Engineering Center, U.S.
Army, August 1964
San Francisco Bay, Sediments Presented at the AAAS National Meeting,
Berkeley, December 28, 1965
Submitted by invitation to California Fish & Game
Predicted Suspended Sediment Inflows to the San Francisco Bay System
Prepared for the Department of the Interior, Federal Water Pollution
Control Administration, S.W. Region, Central Pacific River Basins
Comprehensive Water Pollution Control Project, 33 pp., September 1966
Orthokinetic Flocculation in Water Purification
(with H. Harris and W. Kaufman) Jour. SED, ASCE, 5027, SA6,
pp. 95-111, 1966
Soil Material as a Wastewater Treatment System
(with P. H. McGauhey) Final Report, SERL & School of Public Health,
University of California, Berkeley, 201 pp., 1967
Evaluation of Sludge Thickening Theories (a discussion)
J. ASCE, SA3, pp. 554-558, 1968.
Hydrodynamic Effects on an Interfacial Film
(with L. F. Mockros) Science, pp. 361-363, July 26, 1968
The Movement of Disease Producing Organisms Through Soils
Presented at the Symposium on the Use of Municipal Sewage Effluent
for Irrigation at Louisiana Polytechnic Institute, Ruston, La.,
July 30, 1968
The Physical Characteristics of Erythrocyte Settling in a Liquid Medium
(with R. R. Burton, S. J. Sluka and A. H. Smith) J. Bio-mechanics,
Vol. 2, pp. 389-396, February 1969
r
Ray B. Krone
• Page 7
Shearing Effects on Settling of Activated Sludge
(with R. A. Bradley) Jour. San. Eng. Div., ASCE, pp. 59-79, 1971
Borehole Recharge: The Compatibility of Recharge Water with the Aquifer
Proceedings Artificial Groundwater Recharge Conference, University of
Reading, England, September, 1970
Statement to the Subcommittee of the Committee on Government Operations
House of Representative, Ninety-first Congress, Published in The Nation's
Estuaries: San Francisco Bay and Delta, California, Part II, pp. 107-131,
August 20-21, 1969
Hydraulically Ventilated Underground Filter
(with D. J. Hills) Journal of the Sanitary Engineering Division,
Proceedings of the American Society of Civil Engineers, SA6, pp.
851-866, December 1971
A Field Study of Flocculation as a Factor in Estuarial Shoaling Processes
Technical Bulletin 19, Committee on Tidal Hydraulics, U.S. Army Corps
of Engineers, pp. 1-113, Appendix 1-263, June 1972
Application of Chemical and Electrical Parameters to Prediction of
Erodibility '
(with K. Arulanandan, A. Sargunam, P. Loganathan) Highway Research
Board Special Report 135, Soil Erosion: Causes and Mechanisms,
Prevention and Control, pp. 42-51, January. 26, 1973
Physico-Chemical Factors in Erosion of Cohesive Soils
(with A. Sargunam, P. Riley, K. Arulanandan) Journal of the Hydraulics
Division, Proceedings of the American Society of Civil Engineers, Vol. 99,
No. HY3, pp. 555-558, March 1973
Pore and Eroding Fluid Influences on Surface Erosion of Soil
(with K. Arulanandan and P. Loganathan) Journal of the Geotechnical
Engineering Division, American Society of Civil Engineers, Vol. 101,
No. GTI, Proceedings Paper. 11078, pp. 51-66, January 1975
Finite Element Model for Cohesive Sediment Transport
(with C. R. Ariathurai) Journal of the Hydraulics Division, American
Society of Civil Engineers, Vol. 102, HY3, Proceedings Paper 11987,
pp. 323-338, March 1976
Engineering Interest in the Benthic Boundary Layer
Published in the Proceedings of the North Atlantic Treaty Organization
1974 Conference on the Benthic Boundary Layer, Les Arcs, France,
titled "The Benthic Boundary Layer," I. N. McCave, Ed. Plenum Press,
pp. 143-155, 1976
Ray B. Krone
Page 8
Ultimate Fate of Suspended Material in Estuaries
Proceedings of the Specialty Conference on Dredging and Its
Environmental Effects, Mobile, Alabama, P. A. Krenkle, J. Harrison,
and J. C. Burdic, Eds., pp. 180-201, Published by American Society of
Civil Engineers, 1976
Applications of Predictive Sediment Transport Models
(with C. R. Ariathurai) Environmental Effects and Technology,
Proceedings of WODCON VII, Seventh World Dredging Conference.
pp. 259-272, July 1976
Mathematical Modeling of Sediment Transport in Estuaries
Estuarine Processes, Vol. II, pp. 98-106, 1977
Effects of Physical Alterations
Estuarine Processes, Vol. II, page 1, 1977
Aggregation of Suspended Particles in Estuaries
The Belle W. Baruch Library in Marine Science, Number 7, Estuarine
Transport Processes, U. of South Carolina !Tess, pp. 177-190, 1978
Sedimentation in the San Francisco Bay System
Proceedings of,the San Francisco Bay Symposium, Amer. Assc. for the
Advancement of Science, John Conomos, editor, 25 pages, 1979
A Viscosity-Temperature Relation for Newtonian Liquids
Chemical Engineering Communications, Vol. 22, pp. 161 (1983)
7
• M
RAY B. KRONE & ASSOCIATES RECEIVED
SEDIMENTATION . TIDAL HYDRAULICS
_ MAY n 1988 '
EXPERIENCE IN WATER RELATED HOUSI10
AND COMMERCIAL DEVELOPMENTS 1110FSUPBATCHELOR
R CON COST P V SOBS
t
eputy
Dr. Krone has served as a consultant in the design of small craft harbors for
minimum sedimentation rates and for maintenance of water quality, particularly
control of algae growth, since 1960. A number of these developments include
lagoons with private floats for berthing individual craft. Numerical hydro-
dynamic and transport models and occasionally physical models are used in the
development of desirable designs. Examples include:
Bel Marin Keys, Novato. The flushing procedures for suspending sediment to .
maintain navigable water depths in Novato Creek from the first lagoon to San
Pablo Bay were designed in 1966. Flushing procedures for an additional length of
Novato Creek and the circulation system for maintaining water quality in
additional lagoons were designed recently and are now in operation. Studies have
been completed for further expansion.
Cullinan Ranch, Vallejo. This 1,600 acre planned development would have
included about 650 acres of marina and waterways in land west of Vallejo that
had been reclaimed from marshland in the late 1800's. Services to this project
included design of harbor plans to minimize sedimentation rates, conducting a
sampling program and computations to estimate the resulting sedimentation
rates, planning a dredging program and drying and disposal systems for dredged
sediment, and desian of the waterway flushing system to minimize the concen-
tration of algae. Assistance in permit hearings was provided, and plans for
maintaining water quality were prepared for submittal to the Regional Water
Quality Control Board.
This project has been stopped by interests and an agency who desire the
return of the land to marsh. Future completion of a project on this site can not
be predicted at this time.
Woodlanding/Delta _Coves, Bethel Island. Evaluation and modification of the
proposed development plan for sedimentation rates and suitable flushing were
completed for this project in 1980. Financinq and permit applications have
delayed the project until recently. Present activity includes assistance in
obtaining permits.
.Lighthouse Marina, West Sacramento. Services to this project included
locating the marina entrance and configuring it for minimum sedimentation rates,
evaluating the sedimentation rates throughout the marina, determining the
flushing requirements for control of algae, modeling flood flows to evaluate the
impacts of the project on the capacity of the river channel to convey flood flows
from the Sacramento and American Rivers, and assisting in obtaining permit
approvals. This project has obtained permits and financing and is completing
P.O. BOX 694 DAVIS, CA 95617 TELEPHONE (916) 753.2555/752.1435
i
v
geotechnical and structural engineering design.
Other small craft harbors having entrance, enclosure, and flushing require-
ments planned by Ray B. Krone h Associates include Vallejo Municipal Marina
and its current expansion, Benicia, Pittsburg, and Sacramento Municipal
Marinas, and the South Beach Marina in San Francisco. Foster City Marina and
the Petaluma.Marina are currently in the design stage.
Water Related Developments
4-9-88 Page 2
William F. Jones, Inc. Consulting Engineers William F. Jones, C.E., G.E.
Soil, Foundation and Geological Engineering James B. Baker, C.E.G.
865 Woodside Way, San Mateo, California 94401-1696 Paul A. Grishaber, P.E.
(415) 342-9496 Daniel F. Dyckman, P.E.
Duane A. Pankhurst, B.Sc.
File No. : 179115.1
11th January 1988
John Houston Scott, Esq.
433 Turk Street
San Francisco, CA 94102
Subject: Delta Coves
SETTLEMENT OF OFF-SITE .IMPROVEMENTS
Dear Mr. Scott:
f
A review of work done by our firm in years past, including the Soil and
Geologic Investigation Report of June 1980, reveals we did not comment
specifically on the potential settlements of adjacent properties that
might be caused by the construction of the Delta Coves project. We
stated in conversations and in meetings that we did not .believe there
would be a problem, and this was certainly inferred by our calculations
such as those on sheet 2 of Appendix A.1 of the referenced report.
However, a careful review of our files reveals nothing substantive
which would validate the inferences. In view of your recent enquiry, we
have made further calculations. The following reflect the results of
those °calculations, with comments.
1. Weight of Water. The weight of water in the lagoon system will
just about balance the weight of soil removed for the construction of
the levees. For example, taking the section shown on sheet 7 of
Appendix A.l of - the referenced report, the weight of soil removed from
the lagoon area is about 2,000 p.s. f. The weight of water occupying the
lagoon will , at highest water level , be about 1,800 p.s. f. The$U,hfymatey
soil below the lagoon will feel less pressure on it.
JAN 19 1988
Exhibit K
Martinez, CA 94558
File No. :179115. 1
i
lith January 1988
2. Weight of Levees. The weight of the levees will cause settlement
to occur . Sheet 2 of Appendix A.1 shows that under two conditicns this
Will amount to 3. 6 inches under the center of the levee. The two
conditions are.-
a.
re:a. The water table is below the base of the levee. This will be
true during construction, and represents the heaviest condition of
the levee, for if the water table were within the levee, then
buoyant conditions would prevail , and part of the load would not
bear on the underlying soil. Settlements under those conditions
would be less than under the assumed conditions.
b. The soil has an elasticity of 1 ,000 p.s. i . For the type and
density of soil at the project our judgement is that its
elasticity is nearer to 2,000 p.s. i . than to 1 ,000, a position
borne out by a number of the references cited in the Report.
However, to not underestimate the potential, we quoted the higher
settlement value that results from the use of the lower elasticity
value.
It must be recognized that the weight of the levee will cause a
"dishing" effect, which' will induce settlements in the ground outside
of the physical limits of the levee. We have calculated these, based
both upon the above conditions and the further condition that the
settlement-load relationship is a straight line. The latter tends to
produce higher calculated settlement values than will actually occur ,
i.e. settlements are not under-played; rather they are exaggerated
somewhat.
The results of our calculations show that under the outside toe, or
foot, of the levee slope there will be a settlement of 0 . 6 inches. At a
distance of 7.5 feet further out, towards the existing Bethel Island
improvements, the settlement will be 0. 3 inches. Yet another 7.5 feet
further out again (a total of 15 feet from the outer edge of the levee)
the settlement will be 0. 3 inches.
i
-2-
File No. : .179115.1
llth January 1988
The conclusion to be reached is that the settlements that will be
induced by the construction of 'the levees and lagoon system are
insignificantly small. The lagoons will not induce any settlements at
all . Those from the levees will be so small outside, of the limits of
the levees that they will not be significant, and will not cause damage
to offsite improvements and utilities. We are of the opinion that at
the project boundary itself, which lies at the very closest 20 feet
beyond the foot of the levee slope, settlements induced by the project
will be too small to measure.
Very truly yours
WILLIAM F. JONES, INC.
�RpFE�� SSIp q
No. 448
I�
Exp123189
William F. Jones. , P.E.
Geotechnical Engineer X448 �slF�TECHN�G���Q
lF OF
cc: 2 to Mr . Scott
-3-
4
William F. Jones, Inc. Consulting Engineers William F. Jones, C.E., G.E.
Soil, Foundation and Geological Engineering James B. Baker, C.E.G.
865 Woodside Way, San Mateo, California 94401-1696 Paul A. Grishaber, P.E.
(415) 342-9496 Daniel F. Dyckman, P.E.
Duane A. Pankhurst, B.Sc.
File No . : 488047 . 1
14th April 1988
John Houston Scott , Esq .
433 Turk Street
San Francisco , CA 94102
Subject : The Delta Coves Project
Bethel Island , CA
Dear Mr . Scott :
You have posed a number of questions regarding the potential for
disaster at Bethel Island , or at least the south-east corner of the
Island , should Delta Coves be built . Those questions , and our
responses , follow.
1 . Is there a risk of a catastrophic breach of the existing levees
due to an earthquake , whether fro■ liquefaction or otherwise?
Yes , there is , although one must consider the meaning of the word
' catastrophic ' . Any breach or failure of the levees which permits
water to enter the interior of the Island is a catastrophe . However ,
we perceive that the sense of your question is whether the existence
of Delta Coves increases the chance of that event occurring - a
question that is addressed later in this letter .
We consider the possibility of an instantaneous failure too remote to
be a ■atter of concern . Consider the three possible scenarios , other
than one of deliberate attempts by man to breach the levees , such as
by dynamiting them .
a . Static failure . By this we mean causes of levee failure ,
especially during high water , which include : ( 1 ) Sufficient seepage
through or under the levee to cause a ' boil ' . or blow-out ; (2 ) levee
erosion by current or wave action ; (3) levee overtopping by flood-
flows that exceed levee heights ; and (4 ) structural failures due to
underlying soil characteristics (Ref : 1 , p . 8) .
Characteristically, these .failures involve a valuable time
factor . There is either fore-warning, such as of rising flood-flows
that: will exceed the height of the levee , or there is a physical
manifestation that something is starting to happen , such as when
seepage and/or ' boiling ' appears prior to a blow-out or breaching . In
either case , there is time to take action , whether to control the
situation , or to evacuate the residents .
Exhibit L
File No . : 488047 . 1
14th April 1988
Notwithstanding lurid descriptions given in novels , or inferences
and exaggerations put forth in the news media , we know of no instances
of an instantaneous catastrophic failure of an earthen embankment due
to one of the stated causes , even when the embankments were being
acted upon by heights of water in excess of 100 feet . Fort Peck Dam ,
the Baldwin Hills Dam , and the Teton Dam come to mind - in all these
cases there were preceding hours , indeed days , when signs that failure
was going to occur were observable . The writer himself was directly
Involved in a study of levees at the Arvin-Edison Water Storage
facilities , near Bakersfield , some years ago , where there was a full
12 hours of warning to evacuate prior to an embankment failure .
Bearing in mind the excellent maintenance program , and alert
attention , given by BIMID and the residents of Bethel Island to the
conditions and performance of the levees , it is difficult to imagine
that impending problems would not be observed and acted on in good
time to provide safety for the residents .
b . Dynamic Failure due to Ground Shaking. By this we mean the
collapse of , or damage leading to breaching of , a levee due to lateral
sliding , or base liquefaction , when the ground is shaken by an
earthquake in which a very large amount of energy is released when
there is relative movement on an active geologic fault line . One
cause of such collapse or failure could be by liquefaction of the
soils underlying the levees .
The Soil and Geologic Investigation report prepared by this firm
in 1.980 addresses the question of liquefaction . It is recognized as a
potential hazard , from which the Delta Coves project itself can be
isolated (Ref : 3 . Section 3 . 2 . 1 et seq. , commencing p . 26) . This can
not be said of the existing levees , and raises the question of the
reality of liquefaction-induced failures or damage actually occurring.
The reality appears to be that the realization of the potential
Is very low indeed . For example , in none of the earthquakes
experienced in California ' s recorded history has there been any
reported levee failures in the Delta (or elsewhere in California for
that: matter) . The most significant earthquakes influencing the Delta
have been those of 1892 (Vacaville , Winters and Dixon) (Ref : 1 ) , and
of 1906 (San Francisco) (Ref : 2) . Even with the very high
ground-shaking intensities in the Delta of IX to XI on the Modified
Mercalli Scale where XIII is the maximum possible , no liquefaction or
similar failures were recorded (Ref : 1 ) .
Whilst there were comments at, thetime of significant nearby
earthquakes ( those of January 1980 with epicenters near Livermore )
than "the Delta had probably suffered ' liquefaction ' ' , and collapsed
with widespread flooding. " (Ref : 4 ) , the truth was the very reverse .
Elsewhere (Ref : 1 , p . A-18) , it was noted that it could not be
determined whether a 280-foot slip (not total collapse ) observed at
2
File No . : 488047 . 1
14th April 1988
Bacon Island was caused or only aggravated by the earthquakes , i . e .
still no earthquake-induced failures recorded .
Finally, it must be .noted that although the 1980 Publication on
"Seismicity Hazards in the Sacramento-San Joaquin Delta" (Ref*: 1 )
includes many photographs of earthquake-induced damage , none is of any
location int he Delta .
C . Dynamic Failure due to Earthquake Fault Ground Surface Rupture .
By this we mean the cracking open , or slicing through , of the ground
surface due to an earthquake on a fault , real or imaginary , underlying
Bethel Island.
As with ground shaking effects , one needs to look at the reality for
the realization of the potential . (To explain these terms , consider
the fact that a very large number of structures in California have the
potential of being damaged or destro.yed by a typhoon , for they are not
designed to withstand the buffeting from the forces of typhoon winds .
However , the reality is that it does notmatter , since California does
not experience typhoons sufficiently frequently for this potential to
be addressed . )
The realization of the potential is not capable of rigorous
analysis . We can , therefore, only look at the historical record . In
a definitive study (Ref : 5) , it is stated that :
"To the Authors ' knowledge there have been essentially no
failures or damage to dams caused by displacements of faults
during earthquakes . There are of the order of 25 , 000 dam
structures of moderate size (meaning at least a few 10 ' s of feet
In height , perhaps up to 200 feet) in existence in the world , and
there are records of 500 which have failed or been seriously
damaged in other ways . . . . . (but not by fault displacement ) . "
The Authors also state :
"Even where large earthquakes have occurred near dams , e . g. the
1906 San Francisco , the 1971 San Fernando Valley , and the 1959
West Yellowstone (Hegben) , there have been no failures . . . . .At
Hegben Dam there was a substantial fault break with about 16 feet
vertical movement only 650 feet from the Dam , which led to
moderate slumping and some cracking in the dam , but no threat of
serious trouble developed . "
3
File No . : 488047 . 1
14th .April 1988
It is interesting that a treatise based largely on laboratory testing
and theoretical analysis , reaches a conclusion that supports the
historical observations and experiences reported by Sherard , Cluff and
Allen (Ref : 5) . Shen , Cheney and Sohn , (Ref : 7 ) , conclude in part
that " . . . . . catastrophic failure and emptying of reservoir water is not
likely an immediate threat to embankment dams subjected to sudden
fault movement . "
Under the circumstances , we believe , as stated in 1980 (Ref : 3 ) , that
there can be essentially no basis for concern about the possibility of
failure by ground rupturing .
2 . Will the construction of Delta Coves increase the risk of
liquefaction or other failure of the existing levees?
No , absolutely not . Delta Coves stands alone , and will have no
influence whatsoever on the condition and performance of the existing
levees , except at the entrance channel . At that point , the nature of
the design is that the immediately adjacent sections of the existing
levees will in fact be strengthened . At Delta Coves itself ,
liquefiable and compressible foundation soils will be removed from the
new levee areas , to alleviate any risks .
3 . Will the constructiod of Delta Coves increase the risk that loss
of life will result fro■ a catastrophic breach of the existing
levees?
No . On the contrary , we believe it will decrease the potential .
It must be recognized that if the existing levees are breached, by any
means outlined at the commencement of this letter , the residents on
Stone Road will be at peril . This is true whether or not Delta Coves
Is constructed . The difference between now and the future is that
Stone Road will in effect become a cul-de-sac beyond which waters
flowing through a breach will have somewhat less room in which to
spread , and will , instead , be turned east and west by the barrier of
the Delta Coves southern levee .
If we were to mentally conjure the sudden , instantaneous disappearance
of part of the existing levee , all the way down to its base , the
prospects of the residents on Stone Road are di■ indeed . We hope ,
however , that what .we have already written has demonstrated the
implausibility of such an event . In fact , we tend to rank the
probability of it occurring at the same level as that of a meteor
striking Bethel Island of size and power comparable to the one that
created Winslow crater in Arizona .
4
File No . : 488047 . 1
14th April 1988
If the occurrence of an earthquake capable of producing liquefaction
Is assumed to be a valid proposition , then it is our opinion that this
would lead to the fastest potential failure of any of the modes
discussed in this letter . But how fast is fast? It is certainly not
instantaneous . The progress that leads to the manifestation of
41quefaction may well start during the period of ground shaking, but
the effects are normally not evident for a period of time ranging from
a few to many minutes . It has been reported that in Alaska in 1964
some liquefaction ' boils ' did not appear for as much as 30 minutes
after the cessation of the earthquake . Analyses reported by Seed
(Ref : 6 ) demonstrate a time-lag of 15 minutes for peak pore-pressures
to develop in a susceptible soil following an earthquake , i . e . when
the physical manifestations of liquefaction will appear .
Of. course , in addition to possible distress to the existing levees ,
one must recognize that the houses on .Stone Road are in precisely the
same ,jeopardy from the save liquefaction process as are the levees
themselves . If .liquefaction does occur , it is possible that
structural distress , even partial or total collapse , could be
experienced by some of the existing . residences . If , in addition ,
there is sufficient distress to the levees that water does penetrate
Into the Stone Road area, any residents trapped in their houses face a
grave hazard . The potential for the hazard of entrapment will not be
. changed by the construction of Delta Coves . . With or without Delta
Coves , inasmuch as the Typical ground surface elevation in the Stone
Road area is -5. feet , well below the river level such of the time , any
breach of the existing levees will within .a short time flood the area ,
posing an even greater threat to those trapped in their houses . This
is a circumstance which must be faced . Even assuming that today the
gradient of the water that spreads east and west along Stone Road is
less than it might be when Delta Coves is constructed , those who are
effected by the same process which effects the levees are in danger .
The only hope for those residents who are not entrapped, or who can be
quickly released from entrapment , is to get to high ground , assuming
there is some high ground remaining for sanctuary .
Today , the nearest dependable high ground (defined as ground above an
elevation of +6 feet) is 1500 feet from the houses strung along the
inside toe of the levee on the south side of Stone Road . This is true
for a house - opposite the end of the proposed Palermo Way . For all
other houses the distance to existing high ground is greater . Today ,
to get to that high ground residents will have to scramble across a
soft , probably wet and mushy , peaty surface and/or through a bramble
thicket , as well as clamber over or through a Wire fence . In the
future , if the Delta Coves project is approved , the residents of that
same house will have to move a distance of no more than 450 feet to
get to unquestioned firm high ground of elevation +9 . 5. feet , with
fewer obstructions in the way . For all other houses along the stretch
of Stone Road directly influenced by the Delta Coves construction , the
Y
5
File No . : 488047 . 1
14th April 1988
+ current distance to high ground is longer than 1500 feet , and the
future distance will be no greater than , and in most instances less
than, 450 feet .
In .Summary
The potential for an instantaneous disaster is considered too remote
to quantify .
The construction of Delta Coves will not in any way influence the
integrity or performance of the existing levee .system .
The best mitigation of the supposed hazard of the Stone Road area
being "confined" by the Delta Coves south levee , leading to the
conjecture of a more rapid movement of water in the Stone !toad area if
these is a levee failure , is to construct Delta Coves . The mitigation
is .superior to the conjectured hazard , because of the much shorter
path to safety for the influenced residents .
Very truly yours ���F !'q�
WILLIAM F. -TQN INC. %�� �pN� F. j0 ��\
� r
vF Na. 448
7r -
William F . Jone P .E . �, a
Geotechnical E glneer N. 4 &t TECH�1Z�
0 f C���';
cc : 1 to Mr . Scott
1 to Mr . Jacobsen
1 .to Mr Weisenberg
6
File No . : 488047 . 1
14th April 1988
R E F E R E N C E S
1 . State of California , Department of Water Resources , "Seismicity
Hazards in the Sacramento-San Joaquin Delta , " October 1980 .
2 . U . S . Department of the Interior , "Geologic Maps of the
Sacramento-San Joaquin Delta , " 1982 .
3 . William F . Jones , Inc . , "A Soil and Geologic Investigation for
Delta Coves , Bethel Tract , Contra Costa County , California , " June
1980 .
4 . Oakland Tribune , 26 January 1980 .
5 . Sherard , Cluff and Allen , "Potentially Active Faults in Dam
Foundations , " Geotechnique , September 1974 .
6 . H . Bolton Seed , "Soil Liquefaction and Cyclic Mobility Evaluation
for Level Ground during Earthquakes , " Journal of the Geotechnical
Engineering Division , ASCE , February 1979 .
7 . Shen , Cheney and Sohn , "Rupture of Embankment Dams due to Fault
Movement , " Proceedings of the Trilateral Seminar-Workshop on
Lifeline Engineering, Taipei , Taiwan , November 1985 .
ADDITIONAL REFERENCES .REVIEWED BUT NOT QUOTED
a . Finch , "Earthquake Damage in the Sacramento-San Joaquin Delta, "
California Geology , February 1985 .
b . Newmarch , "Subsidence of Organic Soils., Sacramento-San Joaquin
Delta , " California Geology , July 1981 .
C . Prokopovich , "Tectonic Subsidence in California ' s Sacramento-
San Joaquin Delta , " Bulletin of the Association of Engineering
Geologists , February 1988 .
d . State of California , Department of Water Resources , "Preliminary
Report on Findings and Recommendations based on the Inspection
of Delta Levees during October 1980 , " November 1980 .
e . State of California , Department of Water Resources , "Report on
Causes of Subsidence in the Sacramento-San Joaquin Delta and
A Strategy for Controlling its Rate , " September 1980 .
7
William F� Jones, Inc. - Consulting Engineers William F. Jones, C.E., G.E.
Soil, Foundation and Geological Engineering James B. Baker, C.E.G.
865 Woodside Way, San Mateo, California 94401- Pan. A. Grishaber, P.E.
(415) 342-9496 RECEI�1E�n I F. Dyckman, P.E.
• Dua e A. Pankhurst, B.Sc.
MAY h 1958
C U R R I C U L U M V I T A E
CLERK BOARD OF SUPERV
WILLIAM F. JONES, P.E. By c aAc r co.
•.... oeputy
EDUCATION
University of Newcastle-upon-Tyne (formerly University of Durham), England, B.Sc.
in Civil Engineering, 1949.
California Institute of Technology, M.S. in Civil Engineering, 1950.
PROFESSIONAL REGISTRATION:
California, C.E. 9565 (2/24/55); G.E. 448 (9/9/87)
Nevada, C.E. 1337 (4/17/59)
Hawaii, C.E. 2505 (10/14/69)
PROFESSIONAL EXPERIENCE:
1976 - President, William, F. Jones, Inc., Consulting Engineers, Sunnyvale, and
San Mateo, California.
1973 - 1975 Owner, William F. Jones, P.E., Consulting Engineer, Sunnyvale and San
Mateo, California.
1971 - 1973 President, Gribaldo, Jones and Associates, Consulting Soil, Foundation
and Geological Engineers, Mountain View, California.
1962 - 1971 Vice-President, Gribaldo, Jacobs, Jones and Associates, Soil, Foundation
and Geological Engineers, Mountain View, California.
1958 - 1962 Vice-President of Testing and Controls, Inc., Soil and Materials Testing
Laboratories, Mountain View, California.
1955 - 1958 Chief Civil Engineer, Skidmore, Owings and Merrill, Architects-Engineers,
San Francisco, California.
1952 - 1955 Project Engineer at California Institute of Technology, for U.S. Navy
sponsored research on vibration compaction of soils; also with Frederick
J. Converse, Soil and Foundation Engineers, Pasadena, California.
1950 - 1952 Waterhouse and Rounthwaite, Consulting Civil Engineers of
Newcastle-upon-Tyne, England.
Exhibit M
October 1987
WILLIAM F. JONES, P.E.
Curriculum Vitae - continued
PROFESSIONAL ORGANIZATIONS:
National Society of Professional Engineers (NSPE);
California Society of Professional Engineers (CSPE);
Consulting Engineers Association of California;
U.S. National Committee of International Association
of Soil Mechanics and Foundation Engineering;
Structural Engineers Association of Northern California;
Seismological Society of America;
Engineers Club of San Francisco;
Engineers Club of San Jose;
Soil and Foundation Engineers Association;
National Academy of Forensic Engineers.
HONORS AND POSITIONS HELD:
Rotary International Foundation Fellow;
Member of Sunnyvale Board of Building Code Appeals;
President of Community Associations in Palo Alto and Sunnyvale;
President of Per.insula Chapter, (CSPE);
Vice-Chairman of Professional Engineers in Private Practice Section (PEPP) of NSPE;
President of California Society of Professional Engineers;.
Chairman of Private Practice Section of California Society of Professional Engineers
(CSPE-PEPP); '
Member of Soil and Foundation Committee of Consulting Engineers Council/USA,
and of the Consulting Engineers Association of California;
Chairman of Architects-Engineers Conference Committee of California;
Vice-President of National Society of Professional Engineers (Western Region);
Member of Seismology Committee of the Structural Engineers Association of
Northern California, and of its Site Response Subcommittee, and of its Soil-Structure
Interaction Subcommittee;
Member of Building Codes Committee, and Chairman of its Foundation
Subcommittee, American Society of Civil Engineers and Structural
Engineers Association of Northern California;
Member of Consultants Office Management Committee of NSPE-PEPP;
Chairman of the Registration and Qualifications for Practice Committee of NSPE;
Member of Political Contributions Task Force of NSPE-PEPP;
Chairman of the CSPE-PEPP;
Director of California Society of Professional Engineers;
Governor of NSPE-PEPP.
October, 1987
WILLIAM F. JONES, P.E.
Curriculum Vitae - Continued
NSPE or NSPE-PEPP Committee Activity
Committee on Federal Procurement of A/E Services (NSPE):
Registration and Qualifications for Practice Committee (NSPE) (Four years, of which two
as Chairman);
Awards Committee (NSPE-PEPP);
Directory Committee (NSPE-PEPP)(Chairman);
Consultants Office and Management Committee (NSPE-PEPP);
Membership Committee (NSPE-PEPP);
Professional Development Committee (NSPE-PEPP);
Ad Hoc Committee on Political Contributions (NSPE-PEPP).
CSPE Committee Activity
Numerous. Currently:
Ethical Practices Committee (Chairman);
Nominating Committee;
Past-Presidents' Council;
PEPP Chairman and Representative (Governor) to NSPE-PEPP;
New Building Committee;
Board of Directors of CSPE.
October, 1987