HomeMy WebLinkAboutMINUTES - 01141997 - C1 r
TO: BOARD OF SUPERVISORS °
FROM: J. MICHAEL WALFORD, PUBLIC WORKS DIRECTOR
DATE: JANUARY 14, 1997
SUBJECT: Approve Delta Road Bridge Replacement Project, Knightsen Area.
Project No. 0662-6R4216, CDD-CP # 96-1
Specific Request(s) or Recommendation(s) & Background & Justification
I. RECOMMENDED ACTION:
APPROVE Project, and
FIND, on the basis of the initial study and all comments received, that there is no substantial
evidence that the project will have a significant effect on the environment,
ADOPT the Negative Declaration and Mitigation Monitoring Program (EXHIBIT A) in
compliance with the California Environmental Quality Act, (the custodian of which is the Public
Works Director who is located at 255 Glacier Drive, Martinez), and
DIRECT the Director of Community Development to file a Notice of Determination with the
County Clerk.
DIRECT the Public Works Director to arrange for the $1,250.00 Fish and Game filing fee to be
transferred to the County Clerk.
DIRECT the Public Works Director to arrange for payment of the $25.00 handling fee to the
County Clerk.
DIRECT the Public Works Director to begin right of way acquisition and to prepare contract
plans and specifications for construction.
II. FINANCIAL IMPACT:
The estimated project cost is $700,000, funded by H.B.R.R. funds (80%) and road funds
(20%).
Continued on Attachment: SIGNATURE:
RECOMMENDATION OF COUNTY ADMINISTRATOR
_RECOMMENDATION OF BOARD COMMITTEE
APPROVE OTHER
SIGNATURE(S): /
ACTION OF BOARD ON O/ - /`�' /997 APPROVED AS RECOMMENDED /OTHER_
VOTE OF SUPERVISORS
UNANIMOUS (ABSENT )
AYES: NOES:
ABSENT: ABSTAIN:
Q e29ft that NS is a tett®and eorred OW 69
:mat on aOon taken and entered on the minut®a ft
H:\MAT\DELTA\BONEGDEC.FRM R=d of Supervisors on the date shown.
PHII&MMMELOOrig.Div: Public Works(Design Division) Cleo the
Contact: V.Germany,Design 313-2296
cc: County Administrator
Attn: E. Kuevor C� (�J---
Auditor-Controller
PW Accounting
Construction
Community Development-G.Slusher
B.Fernandez
Delta Road Bridge Replacement Project
January 14, 1997
Page 2
011. REASONS FOR RECOMMENDATION/BACKGROUND:
The project includes replacing the existing deteriorating one-lane timber deck Bailey bridge
over Rock Slough with a 26-ft. wide bridge. The project also includes realigning Delta Road
approximately 100 ft. on the south side and 70 ft. on the north side of the bridge to conform
with the new bridge.
The H.B.R.R. process has determined that the existing bridge on Delta Road at Rock Slough
to be in need of replacement.
The project has been determined to be in compliance with the General Plan. A Negative
Declaration of environmental significance pertaining to this project was published. The Board
has considered the negative declaration together with all comments received during the public
review period and staffs responses to their comments.
W. CONSEQUENCES OF NEGATIVE ACTION:
Delay in approving the project will result in a delay of design and construction and may
jeopardize funding.
EXHIBIT "A"
MITIGATION MONITORING PROGRAM FOR
DELTA ROAD BRIDGE REPLACEMENT PROJECT
This Mitigation Monitoring Program has been prepared for the Delta Road Bridge Replacement
Project in accordance with the California Environmental Quality Act, requiring the establishment
of mitigation monitoring or reporting programs for projects approved by a public agency.
WATER QUALITY/RISK OF UPSET
IMPACT: Removal of existing bridge creosote pilings could result in the release of toxic
materials into Rock Slough.
MITIGATION MEASURES: The existing bridge pilings shall be retained in place and the new
bridge pilings will not be coated with protective coatings having potential toxic characteristics.
If the existing bridge pilings cannot be retained, the Contra Costa County Public Works
Department will consult immediately with the Contra Costa Water District on the proposed debris
containment barrier for a design and installation that will minimize the release of creosoted
substances into the public water supply.
MONITORING AND REPORTING REQUIREMENTS: This mitigation measure will be
incorporated into the contract specifications and will be monitored by the Resident Engineer.
During construction, a record of the mitigation monitoring shall be kept in the Resident Engineer's
file and shall be available to the Public Works Department Environmental Planner upon request.
RISK OF UPSET/HUMAN HEALTH
IMPACT: The project has the potential to release hazardous substances, such as accidental
petroleum spills, during construction.
MITIGATION MEASURES: In the event of any toxic substances discharge into Rock Slough, the
Contra Costa Water District, Diablo Water District, City of Antioch, City of Pittsburg, Southern
California Water Company and the City of Martinez shall be immediately notified by the contractor
or Contra Costa County of the type of discharge, its volume and other information on its
characteristics. Contra Costa County shall use its best efforts to work with these agencies to
contain and remove the discharged substances from the public water supply to a predetermined
site location for remediation.
MONITORING AND REPORTING REQUIREMENTS: This mitigation measure will be
incorporated into the contract specifications and will be monitored by the Resident Engineer.
During construction, a record of the mitigation monitoring shall be kept in the Resident Engineer's
file and shall be available to the Public Works Department Environmental Planner upon request.
H AMATUELTAWIITIGATE.MON
EnwhronmenW QmRfty Act
NOTICE OF
Completion of Environmental Impact Report
Negative Declaration of Environmental Significance
CONTRA COSTA COUNTY COMMUNITY DEVELOPMENT DEPARTMENT
651 Pine Street North Wing- 4th Floor- Martinez, California 94553-0095
,I Telephone: (510) 335-1213 Contact Person: Debbie Chamberlainj�i
Project Description and Location:
**See Attachment "96-1 " for Project Description"
If you require further information regarding the 2Miqct itself, please contact Bill Fernandez of the
County Public Works Department, Design Division, at (510) 313-2294. If you have any comments
regarding the environmental review of this Notice of Intent, please contact Ms. Vickie Germany at
(510) 313-2296 no later than Wednesday, December 19, 1996 at 5:00 p.m.
The Justification/Copy of the Negative Declaration is available for review at the address below:
County Community Development Department (CDD) County Public Works Dept. (PWD)
651 Pine Street, 4th Floor, North Wing 255 Glacier Drive
Martinez, CA 94553-1229 Martinez, CA 94553-4897
(CDD is closed 1st, 3rd &5th Fridays) (PWD is closed every Friday)
Review Period for the Negative Declaration is: November 19, 1996 through December 19, 1996
AP 9 R 12/89 BY
Community Development Department Representative
Attachment "96-11"
Delta Road Bridge Replacement, County File #CP96-1: The project is located at the
Delta Road Bridge over Rock Slough in the Knightsen area of east Contra Costa County.
The area adjacent to Delta Road, north and south of the bridge, is reclaimed land used for
agricultural purposes.
The project consists of replacing the existing deteriorating one-lane timber deck Bailey
bridge over Rock Slough with a 26-ft. wide bridge. The project also includes realigning
Delta Road approximately 100 ft. on the south side and 70 ft. on the north side of the
bridge to conform with the new bridge. A retaining wall will be constructed on the
southeast side of the new bridge to support the realigned bridge approach. A sliver
(approximately 2,000 sq. ft.) of a 553-acre parcel, zoned for agricultural use, may be
acquired for right-of-way purposes. In addition, fences along the existing road will be
relocated to the new right-of-way line. The existing bridge will remain open during
construction of the eastern half of the replacement bridge. Once the eastern half of the
replacement bridge is complete, it will be open while the existing bridge is removed and
the western half of the replacement bridge is completed. The existing bridge is eligible for
replacement under the Federal Highway Bridge Rehabilitation and Replacement (HBRR)
program.
The project will not have a significant effect on the environment. The
recommendation is (based on the following summary of the Environmental
Evaluation:
1. The project will not create unstable earth conditions, changes in geologic
substructures or increase the exposure of people or property to geologic or water
related hazards.
2. A sliver (approximately 2,000 sq. ft.) of a 553-acre parcel, zoned for agricultural
use, may be acquired for right-of-way purposes, however, the parcel will continue
to be viable agricultural land upon completion of the project.
Construction activities will create minor, short-term, temporary impacts. But no significant
impacts will occur since the following best management practices are incorporated into the
project and in project specifications:
3. There will be no significant change in the air quality in the project area.
Construction machinery and vehicles will emit exhaust fumes and possibly
objectionable odors during construction which may temporarily deteriorate air
quality. To minimize,the impact, contract specifications shall stipulate the use of
properly tuned and muffled equipment. Air quality impacts will also be reduced by
eliminating unnecessary idling of machines when not in use. Dust palliatives or
water may be applied to minimize fugitive dust during construction, if warranted.
4. To prevent water quality impacts during construction of the retaining wall, a portion
of the cove on the southeast side of the bridge shall be dewatered. To prevent any
work materials from entering Rock Slough during construction of the new bridge
and removal of the existing bridge, precautions (e.g., the installation of a debris
containment barrier) shall be taken.
5. The project will not result in a significant reduction of any unique, threatened or
endangered species of animals. No new species of animals will be introduced into
the area as a result of the project. To avoid potential impacts to Delta Smelt and
Sacramento Splittail spawn and/or larvae, all in-water work shall be limited to the
time period of August 1 through September 14, unless modified by the U.S. Fish
and Wildlife Service (USFWS). Trees to be removed as a result of construction
shall be replaced with native species appropriate for the area at a 3:1 ratio and
exposed areas will be seeded, which will provide habitat for animal life.
6. Caltrans Standard Specifications will apply regarding construction noise. Limiting
the hours of work to 7:30 a.m. -5:00 p.m., Monday through Friday, unless modified
upon written approval, will also minimize noise impacts to nearby resident.
7. Standard construction safety practices shall be followed during construction to
ensure no accidental release of hazardous substances or increase in the potential
for exposure to these substances. No interference with an emergency evacuation
will result from this project, since providers of emergency services will be notified
of any traffic detours, and traffic control measures will also minimize the risk of
upset. The existing bridge will remain open during construction.
8. Traffic may be diverted within the proposed right-of-way during construction
activities, may create a temporary inconvenience. However, the existing bridge will
remain open during construction of the replacement bridge, and sufficient signs
warning of construction will be installed, which will minimize this impact.
9. No significant negative aesthetics will result from the project. The trees to be
removed shall be replaced with native species appropriate for the area at a 3:1 ratio
and exposed areas will be seeded.
CONTRA PUBLIC WORKS DEPARTMENT
COSTA INITIAL STUDY
COUNTY OF ENVIRONMENTAL SIGNIFICANCE
FILE:0662-6R4216
CP#:q&
PROJECT NAME: Delta Road Bridge Replacement
PREPARED BY: Maureen Tom< DAT . January 3, 1996
REVIEWED BY: DATI�: /
RECOMMENDATIONS:
( ) Categorical Exemption (Class j (r1j Negative Declaration
( ) Environment Impact Report Required ( ) Conditional Negative Declaration
The project will not have a significant effect on the environment. The
recommendation is based on the following summary of the Environmental
Evaluation:
1. The project will not create unstable earth conditions, changes in geologic
substructures or increase the exposure of people or property to geologic or water
related hazards.
2. A sliver (approximately 2,000 sq. ft.) of a 553-acre parcel, zoned for agricultural
use, may be acquired for right-of-way purposes, however, the parcel will continue
to be viable agricultural land upon completion of the project.
Construction activities will create minor, short-term, temporary impacts. But no significant
impacts will occur since the following best management practices are incorporated into the
project and in project specifications:
3. There will be no significant change in the air quality in the project area.
Construction_machinery and vehicles will emit exhaust fumes and possibly
objectionable odors during construction which may temporarily deteriorate air
quality. To minimize the impact, contract specifications shall stipulate the use of
properly tuned and muffled equipment. Air quality impacts will also be reduced by
eliminating unnecessary idling of machines when not in use. Dust palliatives or
water may be applied to minimize fugitive dust during construction, if warranted.
4. To prevent water quality impacts during construction of the retaining wall, a portion
of the cove on the southeast side of the bridge shall be dewatered. To prevent any
work materials from entering Rock Slough during construction of the new bridge
and removal of the existing bridge, precautions (e.g., the installation of a debris
containment barrier) shall be taken.
5. The project will'not result in a significant reduction of any unique, threatened or
endangered species of animals. No new species of animals will be introduced into
the area as a result of the project.;To avoid potential impacts to Delta Smelt and
Sacramento Splittail spawn and/or larvae, all in-water work shall be limited to the
time period of August 1 through September 14, unless modified by the U.S. Fish
and Wildlife Service (USFWS). Trees to be removed as a result of construction
shall be replaced with native species appropriate for the area at a 3:1 ratio and
exposed areas will be seeded,which will provide habitat for animal life.
6. Caltrans Standard Specifications will apply regarding construction noise. Limiting
the hours of work to 7:30 a.m.-5:00 p.m., Monday through Friday, unless modified
upon written approval,will also minimize noise impacts to nearby resident.
7. Standard construction safety practices shall be followed during construction to
ensure no accidental release of hazardous substances or increase in the potential
Initial Study
Delta Road Bridge Replacement -
Page 2
for exposure to these substances. No interference with an emergency evacuation
will result from this project, since providers of emergency services will be notified
of any traffic detours, and traffic control measures will also minimize the risk of
upset. The existing bridge will remain open during construction.
8. Traffic may be diverted within the proposed right-of-way during construction
activities,may create a temporary inconvenience. However, the existing bridge will
remain open during construction of the replacement bridge, and sufficient signs
warning of construction will be installed,which will minimize this impact.
9. No significant negative aesthetics will result from the project. The trees to be
removed shall be replaced with native species appropriate for the area at a 3:1 ratio
and exposed areas will be seeded.
What changes to the project would mitigate the identified impacts. N/A
USGS Quad Sheet:Woodward Island Base Map Sheets: J-28 Parcel #020-160-003
GENERAL CONSIDERATIONS:
1. Location:The project is located at the Delta Road Bridge over Rock Slough in the
Knightsen area of east Contra Costa County (see Figures 1 and 2). The area
adjacent to Delta Road, north and south of the bridge, is reclaimed land used for
agricultural purposes.
2. Project Description: The project consists of replacing the existing deteriorating
one-lane timber deck Bailey bridge over Rock Slough with a 26-ft. wide bridge (see
Figure 3). The project also includes realigning Delta Road approximately 100 ft. on
the south side and 70 ft. on the north side of the bridge to conform with the new
bridge. A retaining wall will be constructed on the southeast side of the new bridge
to support the realigned bridge approach. A sliver(approximately 2,000 sq. ft.)of
a 553-acre parcel, zoned for agricultural use, may be acquired for right-of-way
purposes. In addition, fences along the existing road will be relocated to the new
right-of-way line. The existing bridge will remain open during construction of the
eastern half of the replacement bridge. Once the eastern half of the replacement
bridge is complete, it will be open while the existing bridge is removed and the
western half of the replacement bridge is completed.
The proposed project also includes items # 3-9 from the summary of the
Environmental Evaluation.
3. Does it appear that any feature of the project will generate significant public
concern? [I yes [./] no [] maybe (Nature of concern):
4. Will the project require approval or permits by other than a County agency?
[.1']yes []no Agency Name(s): California Department of Fish and Game, U.S.
Fish&Wildlife Service, U.S.Army Corps of Engineers, and Regional Water Quality
Control Board.
5. Is the project within the Sphere of Influence of any city? No
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VICINITY MAP
DELTA ROAD BRIDGE REPLACEMENT PROJECT
SCALE: 1:24,000 CONTRA COSTA COUNTY
PUBLIC WORKS DEPARTMENT
255 GLACIER DRIVE
SOURCE: USGS,Woodward MARTINEZ, CA 94553
Island,California Quadrangle
FIGURE 3
PLANTING AREA FOR 1
REPLACEMENT TREES -
WILLOWS
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CATTAILS ---BLACKBERRY BUSHES
4—RETAINING WALL
4— COTTONWOOD TREES
PLANTING AREA FOR
REPLACEMENT TREE
RIGHT-OF-WAY
MAY BE ACQUIRED
SITE PLAN
SCALE: 1"=40'
Delta Road Bridge Replacement Project
CONTRA COSTA COUNTY
CEQA ENVIRONMENTAL CHECKLIST FORM
I. Background
1. dame of Proponent: Contra Costa County Public Works Department
2. Address and Phone number of Proponent: 255 Glacier Drive -
Martinez, CA 94553-4897
(510) 313-2000
3. Date of Checklist Submitted: January 3, 1996
4. Name of Proposal, if applicable: Delta Road Bridge Replacement
II. Environmental Impacts
(Explanations of all significant, (S), answers are required on attached sheets.)
*S *I
1. Earth. Will the proposal result in:
a. Unstable earth conditions or changes in geologic substructures?
b. Disruptions, displacements, compaction or overcovering of the soil?
C. Change in topography or ground surface relief features?
d. The destruction, covering or modification of any unique geologic or
physical features?
e. Any increase in wind or water erosion of soils, either on or off the site? _ J
f. Changes in deposition or erosion of beach sands, or changes in siltation,
deposition or erosion which may modify the channel of a river or stream or
the bed of the ocean or any bay, inlet or lake? _ r/
g. Exposure of people or property to geologic hazards such as earthquakes,
landslides, mudslides, ground failure, or similar hazards? _ 1
2. Air. Will the proposal result in:
a. Substantial air emissions or deterioration of ambient air quality?
b. The creation of objectionable odors? _
*Blease Note: "S" is for significant; "I" is for insignificant.
2
C. Alternation of air movement, moisture, or temperature, or any change
in climate, either locally or regionally?
3. Water. Will the proposal result in:
a. Changes in currents, or the course of direction of water movements,
in either marine or fresh waters?
b. Changes in absorption rates, drainage patterns, or the rate and amount
of surface runoff?
C. Alterations to the course or flow of flood waters?
d. Change in the amount of surface water in any water body?
e. Discharge into surface waters, or in any alteration of surface water
quality, including but not limited to temperature, dissolved oxygen
or turbidity?
f. Alteration of the direction or rate of flow of ground waters?
g. Change in the quantity of ground waters, either through direct additions
or withdrawals, or through interception of an aquifer by cuts
or excavations?
h. Substantial reduction in the amount of water otherwise available
for public water supplies?
i. Exposure of people or property to water related hazards such as
flooding or tidal waves?
4. Plant Life. Will the proposal result in:
a. Change in the diversity of species, or number of any species of plants
(including trees, shrubs, grass, crops, and aquatic plants)?
b. Reduction of the numbers of any unique, rare or
endangered species of plants?
C. Introduction of new species of plants into an area, or in a barrier
to the normal replenishment of existing species?
d. Reduction in acreage of any agricultural crop? _
*Blease Note: °"S" is for significant; "I" is for insignificant.
3
5. Animal Life. Will the proposal result in:
a. Change in the diversity of species, or numbers of any species of animals
(birds, land animals including reptiles, fish and shellfish, benthic
organisms or insects)?
b. Reduction of the numbers of any unique, rare or endangered
species of animals? _
C. Introduction of new species of animals into an area, or result in
a barrier to the migration or movement of animals? Y
d. Deterioration to existing fish or wildlife habitat?
6. Boise. Will the proposal result in:
a. Increases in existing noise levels?
b. Exposure of people to severe noise levels?
7. Light and Glare. Will the proposal produce new light or glare?
8. Land Use. Will the proposal result in a substantial alteration of the present
or planned land use of an area? _
9. Natural Resources. Will the proposal result in:
a. Increase in the rate of use of any natural resources?
10. Risk of Upset. Will the proposal involve:
a. A risk of an explosion or the release of hazardous substances
(including, but not limited to, oil, pesticides, chemicals or
radiation) in the event of an accident or upset conditions?
b. Possible interference with an emergency response plan or an
emergency evacuation plan?
11. Population. Will the proposal alter the location, distribution, density, or
growth rate of the human population of an area? _
*P[leaise Note: "S" is for significant; 'T' is for insignificant.
4
12. Housing. Will the proposal affect existing housing, or create a demand
for additional housing?
13. Transportation/Circulation. Will the proposal result in:
a. Generation of substantial additional vehicular movement? V
b. Effects on existing parking facilities, or demand for new parking? _
C. Substantial impact upon existing transportation systems?
d. Alterations to present patterns of circulation or movement
of people and/or goods? _
e. Alterations to waterborne, rail or air traffic?
f. Increase in traffic hazards to motor vehicles, bicyclists or pedestrians?
14. Public Services. Will the proposal have an effect upon, or result in a need for new or altered
governmental services in any of the following areas:
a. Fire protection? _
b. Police protection?
C. Schools?
d. Parks or other recreational facilities?
e. Maintenance of public facilities, including
roads?
f. Other governmental services? _
15. Energy. Will the proposal result in:
a. Use of substantial amounts of fuel or energy?
b. Substantial increase in demand upon existing sources of energy,
or require the development of new sources of energy?
*Blease Note: "S" is for significant; ""iT' is for insignificant.
5
16. Utilities/Service Systems. Will the proposal result in a need for new systems, or substantial
alterations to the following utilities?
a. Power or natural gas? _ 0_
b. Communications systems? _
C. Water? _
d. Sewer or septic tanks? V
e. Storm water drainage? _
f. Solid waste and disposal? d'
17. Human Health. Will the proposal result in:
a. Creation of any health hazard or potential health hazard (excluding
mental health)?
b. Exposure of people to potential health hazards?
18. Aesthetics. Will the proposal result in the obstruction of any scenic vista
or view open to the public, or will the proposal result in the creation of an
aesthetically offensive site open to public view?
19. Recreation. Will the proposal result in an impact upon the quality or quantity
of existing recreational opportunities? _
20. Cultural Resources.
a. Will the proposal result in the alteration of the destruction of a
prehistoric or historic archaeological site? _
b. Will the proposal result in adverse physical or aesthetic effects to a
prehistoric or historic building, structure, or object?
C. Does the proposal have the potential to cause a physical change which
would affect unique ethnic cultural values? _ J
d. Will the proposal restrict existing religious or sacred uses within the
potential impact area? _
*Blease Note. "S" is for significant; "I" is for insignificant.
6
21. Mandatory Findings of Significance.
a. Does the project have the potential to degrade the quality of the
environment, substantially reduce the habitat of a fish or wildlife species,
cause a fish or wildlife population to drop below self sustaining levels,
threaten to eliminate a plant or animal community, reduce the number or
restrict the range of a rare or endangered plant or animal, or eliminate
important examples of the major periods of California history or prehistory?
b. Does the project have impacts which are individually limited, but
cumulatively considerable? (A project may impact on two or more separate
resources where the impact on each resource is relatively small, but where
the effect of the total of those impacts on the environment is significant.) _ V
C. Does the project have environmental effects which will cause substantial
adverse effects on human beings, either directly or indirectly? _
III. Discussion of Environmental Evaluation. (see attached supplement)
IV. Determination
On the basis of this Checklist and Environmental Evaluation:
1 find that the proposed project COULD NOT have a significant effect on the environment, and
a NEGATIVE DECLARATION will be prepared.
❑ I find that although the proposed project could have a significant effect on the environment, there
will not be a significant effect in this case because the mitigation measures described in Exhibit
"A" have been added to the project. A NEGATIVE DECLARATION WILL BE PREPARED.
❑ I find the proposed project MAY have a significant effect on the environment, and an
ENVIRONMENTAL IMPACT REPORT is required.
Date ignatur
Reviewed By:
VG:mat
c:deftalbridge.chk
*Please Note: "S" is for significant; "I" is for insignificant.
ENVIRONMENTAL EVALUATION
Delta Road Bridge Replacement
The project consists of replacing the existing deteriorating one-lane timber bridge over
Rock Slough with a 26-ft. wide bridge (see Figures 1 - 3). The project also includes
realigning Delta Road approximately 100 ft. on the south side and 70 ft. on the north side
of the bridge to conform with the new bridge. A retaining wall will be built on the southeast
side of the bridge to support the realigned bridge approach. In addition, fences along the
existing road will be relocated to the new right-of-way liner The existing bridge will remain
open during construction of the replacement bridge.
In the process of preparing the Checklist and conducting the evaluation, the following
references (which are available for review at the Public Works Department located at 255
Glacier Drive, Martinez, except where otherwise noted) were consulted:
REFERENCES:
1. Contra Costa Resource Mapping System (available at the Community Development
Department, 651 Pine Street, 2nd Floor, North Wing, Martinez, CA 94553)
2. The County General Plan and EIR on the General Plan (January 1991)
3. RAREFIND - California Natural Diversity Data Base (August 8, 1995)
4. U.S. Fish and Wildlife Service Species List for Contra Costa County (April 10,
1995)
5. Field Reviews (March 14, 1995, and October 5, 1995)
6. Sonoma State University - Archaeological Survey (September 5, 1995)
7 Cultural Resources Assessment for Delta Road Bridge Replacement (September
5, 1996)
8. Contra Costa County Important Farmland 1992 map, California Department of
Conservation
9. U.S. Army Corps of Engineer Nationwide Permit with in-water time restriction
conditioned by the U.S. Fish & Wildlife Service (USFWS)
10. Mike Rugg, Department of Fish and Game (personal conversation, December 14,
1995)
1. Earth
(A - G) According to the County Resource Mapping System, soils of Veale Tract (the
southern side of the bridge) consist of Sacramento clay, alkali (nearly level). Piper loamy
soil (0 to 2 percent slope) is found on Holland Tract (the northern side of the bridge). The
Sacramento clay, alkali, has no hazard of erosion, while the Piper loamy soil has a hazard
of wind erosion when soil is exposed or tilled. The project is located on levees constructed
of material hauled in from off-site, prior to 1916. Activities associated with the project will
result in a minor, insignificant change in topography and will also increase the exposure
of soils to water and wind erosion during construction, but these impacts are insignificant
and temporary. Adherence to standard dust control and erosion control practices during
construction, including, but not limited to, general watering of exposed areas and/or use
of chemical stabilizers will minimize erosion impacts. These measures shall be
ENVIRONMENTAL EVALUATION
Delta Road Bridge Replacement
Page 2
incorporated into the construction contract. An earthquake fault with an uncertain location,
runs in a north-south direction in the vicinity of the project and the project area is
susceptible to damage resulting from liquefaction. However, the potential for damage to
the bridge due to liquefaction will be eliminated by the densification of unstable soils
(unconsolidated sand) in the area of the bridge abutments and bents, as needed. Three
methods of soil densification are being considered, including a stone column method,
compaction method, and the vibrating probe method. Based upon the proposed locations
of the abutments, the majority of the densification work will be performed on land and not
in the slough. Replacing a deteriorating bridge with one designed to today's standards,
including performing the densification procedure, will not result in an increase of exposure
to geologic hazards, nor will it result in unstable earth conditions or changes to the
geologic substructure. The project is not expected to result in modifications to the channel
of Rock Slough as a result of changes in deposition or erosion.
2. Air
(A- B) Short-term emissions and objectionable odors are generated during construction
activities, but they are minor and temporary. To minimize this impact, contract
specifications shall stipulate the use of properly tuned and muffled equipment. Air quality
impacts will also be reduced by eliminating unnecessary idling of machines when not in
use. These measures could reduce construction period emissions by up to 50 percent.
Implementation of dust control practices noted in #1- Earth (A - G), will also minimize air
quality impacts.
(C) Realigning the approaches, installing the new bridge, and removing the existing bridge
will not cause an alteration of climate, air movement, moisture, or temperature.
3. Water
(A- 1) Delta Road bridge crosses over Rock Slough (see Figures 2 - 3). According to the
Contra Costa Resource Mapping System, the project area is in a flood hazard area.
However, replacing the bridge and realigning the approaches will not increase the
exposure of people or property to flooding. In addition, the project will not impair the flow
of water in marine or fresh waters, nor will it alter the course or flow of flood waters. The
rate and amount of runoff is not expected to substantially increase due to the project's
impervious surface area. Although Rock Slough is the intake for the Contra Costa Water
District's supply, the project will not result in a substantial reduction of the amount of water
available for this water supply.
A retaining wall is proposed at the toe of the southeast embankment of the bridge. To
prevent water quality impacts during construction of the retaining wall, a portion of the
cove on the southeast side of the bridge shall be dewatered. To prevent any work
materials from entering Rock Slough during construction of the new bridge and removal
of the existing bridge, precautions (e.g., the installation of a debris containment barrier)
ENVIRONMENTAL EVALUATION
Delta Road Bridge Replacement
Page 3
shall be taken. According to water quality experts with the Department of Fish and Game
(Rugg, December 14,1995), piledriving in the slough is not likely to create significant water
quality impacts. Since soil densification procedures would have similar or lesser impacts
than pile driving (see #1-Soils), no significant water quality impacts will result from this
procedure. Standard construction safety practices (see #2-Air and #13-Transportation/
Circulation), shall be followed in order to reduce the possibility of a spill of gasoline, oil,
or other pollutants which could have a significant impact-on water quality.
4. Plant
(A- D) The County Resource Mapping System, field reviews, review of USFWS Species
List and RAREFIND showed no unique, threatened, or endangered species of plants in
the project area. Plant life in the project area consists of riparian vegetation, including a
small stand of four cottonwood trees (Populus fremontii), ranging in size from 12 to 18-
inches in diameter at breast height (dbh), on the southeast bank and some shrubby willows
(Salix sp.) on the southwest, northeast and northwest banks (see Figure 3). The
understory on the north and south banks consists of blackberry bushes. Wetland
vegetation is limited to small patches of water hyacinths (Eichhornia crassipes) and
cattails (Typha sp.) on the southwest, northeast, and northwest banks. The project will
result in the removal of the cottonwood trees and blackberry bushes on the southeast side
of the bridge. Trees shall be replaced with native species (up to one-gallon size) at a 3:1
ratio (i.e., three trees planted for each one removed). Disturbed areas will be seeded with
native grasses and flowers. The project will not create a barrier to the normal
replenishment of existing species.
Although a sliver (approximately 2,000 sq. ft.) of a 553-acre parcel, zoned for agricultural
use, may be acquired for right-of-way purposes, the parcel will continue to be viable
agricultural land upon completion of the project.
5. Animal Life
(A - D) The project will not result in a significant reduction of any unique, threatened or
endangered species of animals according to the County Resource Mapping System, field
reviews, and review of USFWS Species List and RAREFIND. No new species of animals
will be introduced into the area as a result of the project. To avoid potential impacts to
Delta Smelt and Sacramento Splittail spawn and/or larvae, all in-water work shall be
limited to the time period of August 1 through September 14, unless modified by the U.S.
Fish and Wildlife Service (USFWS). Trees to be removed as a result of construction shall
be replaced with native species appropriate for the area at a 3:1 ratio and exposed areas
will be seeded, which will provide habitat for animal life. In addition, the project will not
result in the deterioration to existing fish or wildlife habitat.
ENVIRONMENTAL EVALUATION
Delta Road Bridge Replacement
Page 4
6. Noise
(A & B) The County Resource Mapping System for the project area does not indicate a
noise level along Delta Road for the year 2005. The dominant source -of noise in the
project area comes from vehicles using Delta Road (see,Figure 2).
In general, construction activities produce noise levels-of 86 dBA at 50 feet, while pile
driving produces a noise level of 100 dBA at 50 feet, which is well below the threshold of
pain of 120-140 dBA. Best management practices noted in #2 -Air (A & B), and limiting
work hours to 7:30 a.m. -5:00 p.m., Monday through Friday, unless modified upon written
approval, reduce construction noise levels and shall be incorporated as part of the
construction contract.
Once the project is complete, the realigned bridge approach will be less than ten ft. closer
(i.e., instead of the bridge approach being 60 ft. from the residence, the road will be moved
to approximately 50 ft. away) to the residence on the southeast side of Delta Road,
however, since the project will not significantly increase the capacity of the roadway
outside of the project limits, it will not result in a noise increase of more than six decibels,
nor will the noise standard of 60 dB at the exterior of the residence be exceeded,
therefore, no significant impacts will result from the proposed project (per General Plan
E I R pp. 4.6-80 - 81).
7. Light and Glare
Replacing the Delta Road bridge with a wider bridge and realigning the bridge approach
will produce a minor, insignificant amount of new light or glare.
8. Land Use
Replacing the Delta Road bridge and realigning the approaches will increase the safety
at the Delta Road crossing of Rock Slough. Capacity of the roadway outside of the project
limits will not increase. The project will not result in a substantial alteration of the present
or planned land use of an area. The existing land use within the project limits is
agricultural. This area is classified as farmland of statewide importance. The project may
change less than 2,000 square feet of the parcel on the southeast side of the bridge, which
is an insignificant impact (see Figure 3). If the right-of-way is required, the land owner will
be compensated for the loss of property.
The project is consistent with the County General Plan Transportation and Circulation
Element Goal #5-A (To provide a safe, efficient and balanced transportation system), Goal
#5-B (To coordinate the provision of streets, roads, transit and trails with other
jurisdictions), Policy#5-8 (Existing circulation facilities shall be improved and maintained
by eliminating structural and geometric design deficiencies), and Policy #5-16 (The design
ENVIRONMENTAL EVALUATION
Delta Road Bridge Replacement
Page 5
and the scheduling of improvements to arterials and collectors shall give priority to safety
over other factors including capacity).
9. Natural Resources
During construction the project will use paving materials (i.e., asphalt) which will not
significantly impact this resource. The use of oil and gasoline to operate the machinery
for construction purposes is negligible and of a short-term, temporary nature. -Best
management practices noted in #2 - Air will minimize the consumption of natural
resources.
10. Risk of Upset
(A) The project has the potential to release hazardous substances, such as accidental
petroleum spills, during construction. Per specifications, standard construction safety
practices (see #2-Air and #13-Transportation/Circulation) shall be followed during
construction to ensure no accidental release of hazardous substances or increase the
potential for exposure to these substances. The County Resource Mapping System for the
project area did not identify any petroleum pipelines or electric transmission lines.
(B) No interference with an emergency evacuation will result from this project. Providers
of emergency services will be notified of any traffic detours. As discussed in #13 (D & F) -
Transportation/Circulation, the traffic control measures will also minimize the risk of upset.
The existing bridge will remain open during construction of the eastern half of the
replacement bridge. The eastern half of the new bridge will be open during the removal
of the existing bridge and construction of the western half of the new bridge.
11. & 12. Population & Housing =
The project will not result in a change in the location, distribution, density, or growth rate
of human population in the area. The project will not affect existing housing, or create a
demand for additional housing (see #8 Land Use).
13. Transportation and Circulation
(A - F) The Delta Road bridge is the only access to Holland Tract in the Delta. The
average daily vehicle trips on Delta Road are 269. The existing one lane, deteriorating
timber bridge is substandard with respect to current standards in width and decking
material. While the 26-ft. wide replacement bridge will increase the safety on Delta Road,
it will not significantly increase the capacity of the roadway outside the project limits.
The project is consistent with the Transportation and Circulation Element of the General
Plan (see #8 - Land Use). Replacing the bridge and realigning the approaches will not
ENVIRONMENTAL EVALUATION
Delta Road Bridge Replacement
Page 6
generate additional traffic, increase the demand for additional parking, alter circulation
patterns or impact existing transportation systems, except during construction when
vehicles associated with those activities utilize the local street system; however, the
amount of additional traffic is insignificant. Traffic may be diverted within the proposed
right-of-way during construction activities, which may create a temporary inconvenience.
However, the existing bridge will remain open during construction of the replacement
bridge, and sufficient signs warning of construction will be installed, which will minimize
this impact. The project will not alter waterborne, rail or air traffic as no water, rail or air
transportation facilities are located in the immediate vicinity of the project area.
14. Public Service
(A- D, F) The bridge replacement and road realignment will not increase the need for fire
or police protection, schools, parks, or other governmental services.
(E) Delta Road is currently maintained by the County. Periodic maintenance of road
improvements will continue to be performed by the County.
15. Energy
Minor amounts of non-renewable fuel resources will be consumed during construction, but
this is a short-term, temporary and minor impact. Eliminating unnecessary idling of
machines when not in use and using properly tuned equipment, as mentioned in #2 - Air
(A - C) minimize the consumption of energy resources.
16. Utilities
The project will result in the relocation of some utilities and all relocation activities shall be
coordinated with the appropriate utility agencies.
17. Human Health
The project has the potential to release hazardous substances during construction.
Potential health hazards due to accidental petroleum spills shall be minimized by following
best management practices noted in #10 - Risk of Upset (A). Air quality impacts, which
could affect human health, can be minimized by the measures noted in # 2 -Air (A & B).
The project will not create any known health hazard or increase the potential for exposure.
18. Aesthetics
As mentioned in #4 - Plants, four cottonwood trees will be removed as a result of the
ENVIRONMENTAL EVALUATION
Delta Road Bridge Replacement
Page 7
realigning the bridge approaches (see Figure 3). Since the trees will be replaced at a 3:1
ratio, within the existing right-of-way upon completion of the project, no significant impacts
will result from the project.
19. Recreation
The County Resource Mapping System and the field reviews did not identify any
recreational opportunities in the project area. As mentioned in #13 - Circulation and
Transportation, Delta Road serves as the only access to Holland Tract, where several
marinas are located. The project itself will not affect these recreational areas, however,
access to the areas may be delayed as a result of construction activities.
20. Cultural Resources
(A - D) The County General Plan has designated the project area as an archeological
moderately sensitive area. However, according to the County Resource Mapping System,
the Cultural Resources Assessment , the Contra Costa Historical Society and a records
search of the Northwest Information Center at Sonoma State University, no historical or
archaeological sites exist within the project area. Neither the Delta Road Bridge, nor the
levees are historic structures. In addition, construction activities will only occur in areas
already previously disturbed, such as on the levees. The contract specifications shall
include measures related to discovery of cultural resources.
21. Mandatory Findings of Significance
(A - C) Due to construction equipment, air quality may be temporarily degraded at the
project site. However, no permanent long-term impacts will result (see #2 - Air). The
proposed project will not substantially reduce the habitat of a fish or wildlife species, nor
will it cause fish and wildlife population to drop below self sustaining levels. In addition,
the project will not threaten to eliminate a plant or animal community, reduce the number
or restrict the range of a rare or endangered plant or animal (see #4 - Plant Life and #5 -
Animal Life). The project does not have the potential of eliminating examples of the major
periods of California history or prehistory (see #20 - Cultural Resources). There are no
cumulative impacts associated with the project. In addition, there will be no adverse
environmental effects on human beings (see #17 - Human Health).
:mat
defta\bridge.sup
CONTRA COSTA
--------- 1AlATER DISTRICT
C=D 1331 Concord Avenue RECEIVED
P.O.Box H2O
Concord,CA 94524
190,1
(510)688-8000 FAX(510)688-8122 D E 6
DESIGN
PUBLIC WORKS DEPT
December 19, 1996 Via Fax 5101313-2333
Directors
Joseph L.Campbell Vickie Germany
President Contra Costa County
James Pretti Public Works Department
Vice President 255 Glazier Drive
Elizabeth R.Anello Martinez, CA 94553 -4897
Bette Boatmun
Noble O.Elcenko,D.C. Subject: Comment on Delta Road Bridge Replacement Proposed
Walter J.Bishop CEQA Negative Declaration
General Manager
Thank you for the opportunity to review and comment on the Notice of Negative
Declaration of Environmental Significance on the Delta Road Bridge Replacement
Project. The Contra Costa Water District (CCWD) comment covers the Water Quality
section(3.e.)contained in the Environmental Checklist Form. The Project is not within the
existing CCWD service area boundaries. The reason for CCWD's comment is that the
Project construction will occur in and over Rock Slough, which contains the raw water
supply (from the Central Valley Project)used by CCWD and its raw water customers for
treatment and distribution to over 400,000 residents,businesses,industries and other users
in Contra Costa County. Rock Slough conveys this raw water supply to the Contra Costa
Canal, located approximately 1.2 miles to the west of the Project.
The Project is the replacement of the existing deteriorating one-lane timber bridge over
Rock Slough with a 26-foot wide two lane bridge. The Project also includes realigning
Delta Road approximately 100 feet on the south side and 70 feet on the north side of the
bridge to conform with the new bridge. A retaining wall will be built on the southeast side
of the bridge to support the realigned bridge approach. In addition, fences along the
existing road will be relocated to the new right-of-way line. The existing bridge will
remain open during construction of the replacement bridge. The Project is located at the
Delta Road bridge over Rock Slough in the Knightsen area of east Contra Costa County.
The area adjacent to Delta Road, north (Holland Tract) and south (Veale Tract) of the
bridge, is reclaimed land used for agricultural purposes.
CCWD would generally comment that the Federal Endangered Species Act (FESA),
including the recent listing of the California red-legged frog, should be addressed in the
environmental document, and encourages agencies to coordinate, if necessary, with the
U.S. Fish and Wildlife Service. CCWD notes that FESA issues are discussed in the Plant
Life and Animal Life sections (4. and 5).
Preliminary discussions with the Contra Costa County Public Works Department (see
attached CCWD comment letter dated September 18, 1996 on the Preliminary Project
Notice) indicated that the original creosoted pilings supporting the existing bridge
structure will be retained in order to prevent any disturbance and release of toxic materials
into the municipal water supply. It was also indicated that the new bridge would not
contain pilings with creosote or other protective coatings with toxic characeristics.
However, the Project Description in the Notice does not indicate that the existing pilings
will be retained and that the new pilings will not have toxic coatings. In order to provide
Delta Bridge Road Replacement Negative Declaration
December 19, 1996
Page 2
greater assurance that water quality is protected during the Project construction, it is
requested that the following mitigation measure be included as part of the adoption of the
Negative Declaration:
Mitigation Measure 1. The existing bridge pilings shall be retained in place and
the new bridge pilings will not be coated with protective coatings having
potential toxic characteristics. If the existing bridge pilings cannot be retained,
the Contra Costa County ]Public Works Department will consult immediately
with the Contra Costa Water District on the-proposed debris containment
barrier for a design and 'installation that will prevent the release of creosoted
substances into the public water supply.
Under Checklist element 10., Risk of Upset and Checklist element 17.,Human Health it is
indicated that the Project has the potential to release hazardous substances, "such as
accidental petroleum spills, during construction". The approach to prevent such
occurences is to follow "standard construction safety practices" as the best management
practices. However, there is no provision indicated on how an accidental spill would be
contained, nor any requirement that CCWD is immediately notified if toxic substances are
within the vicinity of the Contra Costa Canal. Such immediate notification would allow
CCWD to take actions that could prevent contaminated waters from either(1) entering the
Canal, or(2)being withdrawn by customers (note: Pumping Plant No. 1 is located 4 miles
from the Canal intake and the Randall-Bold Treatment Plant turnout is located
approximately 8.4 miles from the Canal intake, which serves approximately 15,000
residential customers in Oakley.) In order to provide an emergency action to protect
human health during the Project construction, it is requested that the following mitigation
measure is included as part of the adoption of the Negative Declaration:
Mitigation Measure 2. In the event of any toxic substances discharge into Rock
Slough, the Contra Costa Water District, Diablo Water District, City of Antioch,
City of]Pittsburg, Southern California Water Company and the City of Martinez
shall be immediately notified by the contractor or Contra Costa County of the
type of discharge, its volume and other information on its characteristics. Contra
Costa County shall use its best efforts to work with these agencies to contain and
remove the discharged substances from the puhlic water supply to a
predetermined site location for remediation.
In order to implement the requested mitigation, it requested that a Mitigation Monitoring
and Reporting Plan is adopted by the Contra Costa County Board of Supervisors at the
time of the adoption of the Negative Declaration.
If you have any questions on the comments or require further information on the CCWD
or the Contra Costa Canal system, please contact Dennis Pisila, Senior Planner at
510/688-8119.
Sincerely,
G ��
Gregory Gartrell
Director of Planning
Attachment: CCWD letter dated September 18, 1996
GG/DP
cc: Joel A Medlin,Field Supervisor, U.S. Fish and Wildlife Service, Sacramento
Robert Edwards, Chief,Engineering,Maintenance & Operation, USBR,Tracy
Mike Yeraka, General Manager,Diablo Water District, Oakley
Stan Davis, Director of Public Works, City of Antioch
Robert Soderbery, Director of Public Works, City of Pittsburg
Dick Leonard, Southern California Water Company,Bay Point
Richard Singletary, Superintendent,,, Water Treatment Plant,City of Martinez
Bill Fernandez , Public Works Department, Contra Costa County
Debbie Chamberlain, Community Development Dept., Contra Costa County
Contra Pub is Works Department J. Michael Walford
Public Works Director
Costa 255 Glacier Drive
Count Martinez, California 94553-4897 Milton F. Kubicek
FAX: (510) 313-2333 Deputy-Engineering
Telephone: (510) 313-2000 Patricia R. McNamee
Deputy-Operations
December 31, 1996 Maurice M. Shiu
Deputy-Transportation
S. Clifford Hansen
Deputy-Administration
Our File- Delta Road Bridge Replacement Project
Project No. 0662-6R4216, CP 96-01
Gregory Gartrell, Director of Planning
Contra Costa Water District
1331 Concord Avenue
Concord, CA 94524
Dear Mr. Gartrell:
Thank you for your response to the November 19, 1996, "Notice of Intent to Adopt a
Negative Declaration"for the proposed Delta Road Bridge Replacement Project, CP# 96-
01 . The mitigation measures suggested in your December 19, 1996, letter have been
incorporated into a Mitigation Monitoring Program (see EXHIBIT "A").
The Negative Declaration and the Mitigation Monitoring Program are scheduled to go
before the Contra Costa County Board of Supervisors on Tuesday, January 14, 1997. If
you have any questions, please contact Maureen Toms at (510) 313-2366.
Sincere)
Vickie Germany, AICP
Environmental Planner
Design Division
VG:matjlg
cc: P.McNamee,Administration
M.Hollingsworth, Design
D.Regan, Design
H:\MAT\DELTA\CCWD.RSP
G:\DESIGN\MAT\CCWD.RSP
EXHIBIT "A"
MITIGATION MONITORING PROGRAM FOR
DELTA ROAD BRIDGE REPLACEMENT PROJECT
This Mitigation Monitoring Program has been prepared for the Delta Road Bridge Replacement
Project in accordance with the California Environmental Quality Act, requiring the establishment
of mitigation monitoring or reporting programs for projects approved by a public agency.
WATER QUALITY/RISK OF UPSET"
IMPACT: Removal of existing bridge creosote pilings could result in the release of toxic
materials into Rock Slough.
MITIGATION MEASURES: The existing bridge pilings shall be retained in place and the new
bridge pilings will not be coated with protective coatings having potential toxic characteristics.
If the existing bridge pilings cannot be retained, the Contra Costa County Public Works
Department will consult immediately with the Contra Costa Water District on the proposed debris
containment barrier for a design and installation that will minimize the release of creosoted
substances into the public water supply.
MONITORING AND REPORTING REQUIREMENTS: This mitigation measure will be
incorporated into the contract specifications and will be monitored by the Resident Engineer.
During construction, a record of the mitigation monitoring shall be kept in the Resident Engineer's
file and shall be available to the Public Works Department Environmental Planner upon request.
RISK OF UPSET/HUMAN HEALTH
IMPACT: The project has the potential to release hazardous substances, such as accidental
petroleum spills, during construction.
MITIGATION MEASURES: In the event of any toxic substances discharge into Rock Slough, the
Contra Costa Water District, Diablo Water District, City of Antioch, City of Pittsburg, Southern
California Water Company and the City of Martinez shall be immediately notified by the contractor
or Contra Costa County of the type of discharge, its volume and other information on its
characteristics. Contra Costa County shall use its best efforts to work with these agencies to
contain and remove the discharged substances from the public water supply to a predetermined
site location for remediation.
MONITORING AND REPORTING REQUIREMENTS: This mitigation measure will be
incorporated into the contract specifications and will be monitored by the Resident Engineer.
During construction, a record of the mitigation monitoring shall be kept in the Resident Engineer's
file and shall be available to the Public Works Department Environmental Planner upon request.
H:MATUELTAWIITIGATE.MON