HomeMy WebLinkAboutMINUTES - 05051992 - H.2 TO: BOARD OF SUPERVISORS
FROM: TRANSPORTATION COMMITTEE
DATE: May 5, 1992
SUBJECT: Soundwalls on Interstate 680.
SPECIFIC REQUEST(S) OR RECOMMENDATION(S) &BACKGROUND AND JUSTIFICATION \
I. Recommended Action:
1. After receiving considerable written comments and testimony at the public hearing, as well as
reviewing the proposal by Caltrans, the Transportation Committee recommends that the Board
of Supervisors reaffirm their support for the mitigation of noise impacts on Interstate 680 in the
Alamo area, including the installation of the proposed three walls, under the following conditions:
a. Request Caltrans to monitor the noise levels at distant receptors before these new walls
are installed and continue to monitor the noise levels after the walls are installed.
b. Request Caltrans to completely cover the soundwalls installed along the edges of the
road with vines at the earliest possible date.
C. Request that Caltrans include the landscaping of the Stone Valley Road interchange as
part of the highway planting project on Interstate 680.
d. Request Caltrans to commit to retrofit the soundwalls, including the use of sound
absorptive materials, if the study shows adverse noise impact to distant receptors and
the vines do not help in absorbing the noise energy.
e. Request Caltrans staff to make themselves available to work with community groups, as
well as the San Ramon Valley Regional Planning Commission, to review the studies
described above and to consult in the selection of a course of action, if required.
Continued on Attachment: X SIGNATURE:
_ RECOMMENDATION OF COUNTY ADMI ISTRATOR
RECOMMENDATION OF BOARD C EE
APPROVE _ OTH
SIGNATURE(S):
ACTION OF BOARD ON May 5, 1992 APPROVED AS RECOMMENDED x OTHER _
VOTE OF SUPERVISORS
x UNANIMOUS (ABSENT -- )
AYES: NOES:
ABSENT: ABSTAIN:
I hereby certify that this is a true and correct copy of
MMS:eh:fp an action taken and entered on the minutes of the
c:B05.t5 Board of Supervisors on the date shown.
ATTESTED: Jr, /? ? ;?.
Orig. Div: Transportation Committee PHIL BATCHEL16R,Clerk of the Board
cc: Community Development of Superoleors and County Administrator
Public Works
Caltrans (via P.W.D.) � L —'
C.T.C. (via P.W.D.)
loo--taln;mLA 10swcO to
Soundwalls on Interstate 680
May 5, 1992
Page 2
I. Recommended Action: (Cont.)
2. Direct the Public Works Director to:
a. Transmit the Board's decision to Caltrans.
b. Transmit to the California Transportation Commission (CTC), the Board's concern about
the cost of soundwalls and the materials currently allowed for soundwall construction and
express our support of the effort by CTC to study alternative designs and alternative
materials for soundwalls.
C. To work with Caltrans to implement the requests by the Board.
d. To seek legislation to limit the height of the exhaust stack (mufflers) on new trucks.
e. To work with the Contra Costa Transportation Authority (CCTA) to develop a program so
that new home buyers will have knowledge of the County's future transportation plans
and thereby be able to assess the potential impacts to properties they may be interested
in purchasing.
II. Financial Impact:
None. Except staff time will be involved in working with Caltrans to implement the Board's
requests.
III. Reasons for Recommendations and Background:
As part of the widening of Interstate 680 from Rudgear Road to the Alameda County line,
extensive soundwalls are included to mitigate the adverse impact of future traffic noise on
residents living near the freeway. Caltrans has spent over two years working with design review
committees in San Ramon and Danville and with the Alamo Improvement Association to develop
the architectural treatment of the soundwalls.
After the locations of soundwalls were decided and design of the soundwalls was underway, at
the request of local residents, Caltrans studies two more areas and concluded that they meet
the criteria for soundwalls. These areas are at the north-east corner of the Stone Valley Road
Interchange and on the west side of the freeway by Kemline Court. A project to construct these
two additional soundwalls is scheduled for next year.
After most of the soundwalls were built, certain residents became very critical of the soundwalls
and claimed that the soundwall construction violates the scenic highway designation of Interstate
680. Other residents living further away from the freeway alleged that the noise levels in their
residences have actually increased.
Caltrans requested that the Board of Supervisors reaffirm its support to the construction of
soundwalls before they continue with the two additional segments of the soundwall and to
complete the remaining segment north of Livorna Road on the west side of the freeway.
On April 7, 1992 the Board referred this item to the Transportation Committee for recommenda-
tion.
At the April 20 Transportation Committee meeting, 53 speakers addressed the Committee on
this matter. In addition, the Committee received over 1000 signatures petitioning Caltrans to
remove the soundwall and to restore the scenic quality of Interstate 680. The Committee also
received over 300 signatures urging the Board to reaffirm its support to the construction of the
soundwalls.
The Committee feels that noise is a significant adverse impact to nearby residents. Interstate 680
is a major inter-regional route that carries not only local traffic but through traffic originated
outside the County. In recent years, traffic on Interstate 680 has increased to a point that the
.. a
Soundwalls on Interstate 680
May 5, 1992.
Page 3
III. Reasons for Recommendations and Background: (Cont.)
freeway is congested for long periods during commute periods. The Committee is sympathetic
to these residents' problems.
The Committee is very concerned about the claims from residents living further away from the
freeway that the noise level at their residences have increased. Caltrans has assured the
committee that they have been working diligently to resolve this problem. It appears that the
solution to this problem will take time and the Committee feels that the Public Works Director
should provide the Board with periodic updates on Caltrans' progress.
The Committee is concerned about the scenic quality of the freeway. This impact, however, can
be mitigated by extensive landscaping to soften the visual impact of the soundwalls. Throughout
the entire public meeting, no resident in Alamo complained about the soundwall blocking their
view of Mt. Diablo or the Las Trampas Ridge. The Committee feels that the soundwalls will not
affect the status of Mt. Diablo as the landmark of this County nor will it affect the beauty of the
Las Trampas Ridge when viewed from other locations.
The Committee is also concerned about the height of the soundwalls. We were told that the
high walls are needed to make sure that the noise from truck exhausts stacks are blocked. With
the new emission standard for diesel trucks,the Committee wants to introduce legislation limiting
the height of exhaust stacks so that future soundwalls do not have to be as high.
One of the reasons the soundwalls became an issue was that, at the time the project was
designed, concrete in the form of blocks or pre-casted panels was the only approved material.
This severely restricted the ability of landscape architects to design walls to fit the surrounding
landforms. The California Transportation Commission is looking into alternative material for
soundwalls. The Board should express its support to that effort.
IV. Consequences of Negative Action:
Negative action on the part of the Board will bring this item back to the Transportation
Committee for further study. Caltrans may decide on this issue without the benefit of knowing
the Board's position.