RPVCCA_SR_2011_01_18_09_San_Ramon_Canyon_Project_Study_ReportCITY OF
MEMORANDUM
RANCHO PALOS VERDES
TO:
FROM:
DATE:
SUBJECT:
REVIEWED:
Project Manager:
HONORABLE MAYOR &CITY COUNCIL MEMBERS
RAY HOLLAND,INTERIM DIRECTOR OF PUBLIC ~
WORKS
January 18,2011
SAN RAMON CANYON -PROJECT STUDY REPORT
CAROLYN LEHR,CITY MANAGERc:&-.
Alan Braatvedt,Project Enginee~
RECOMMENDATIONS
1.Receive and File the Project Study Report for San Ramon Canyon Drainage;
2.Set March 1,2011,during the regularly scheduled City Council Meeting,as the
date to conduct a Public Workshop for the San Ramon Canyon Project Study
Report.
BACKGROUND I ANALYSIS
Conditions within the San Ramon Canyon contribute to a serious threat to the
accessibility of the City from the east during rain events due to flooding on 25 th Street.
Land movement and erosion within the canyon are creating a scenario for potential loss
of the access corridor along Palos Verdes Drive East.To address these threats,City
Council awarded a contract to Harris and Associates on March 16,2010 to produce a
Project Study Report for the San Ramon Canyon Drainage System.The project studies
included tasks like:the production of a detailed topographical survey,geological
investigation and report,a biological review,an environmental study,and production of
a number of storm drainage designs.The information was used to generate the Project
Study Report,which evaluated the various designs and made a recommendation of the
most suitable alternative.
The report proposes various alternatives and will be used as the basis for a final design
and can be used as a tool to solicit support and funding for the project.
Two of the alignments explored start adjacent to the upper PVDE switchback,and take
into account the feasibility of the design,constructability,geological considerations,
environmental impacts and right-of-way requirements.
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•One alignment follows the natural stream-bed and relies on the existing storm
drainage system (2A)in the City of Los Angeles beginning at 25 th Street.The
existing system has some major shortcomings,will require purchasing right of way,
and will require considerable coordination with outside agencies.
•The recommended alignment (1A)is totally within the City of RPV.The pipe would
run through a tunnel that extends from the upper switchback to an existing
easement in Shoreline Park south of Palos Verdes Drive South. From there it runs
parallel to the City boundary,within RPV,underground to its discharge point onto
the beach.
The Project Study Report is available for review at City Hall and is on file with the City
Clerk's Office.Staff proposes to present the Project Study Report in greater detail to
City Council at a workshop.Staff is suggesting scheduling the Workshop for March 1,
2011 to facilitate discussion on the merits of the designs.
Pursuant to City Council direction.-fMarch 16,2010),Harris &Associates is designing a
shovel ready project to provide short term stability for the PVDE Switchback.The
establishment of beacons to monitor the stability of the area in and around the
switchbacks and cataloging the ongoing bank erosion in the vicinity of the switchback is
also underway.Staff intends to present the shovel ready project and report on the
canyon monitoring at a Workshop in March.
FISCAL IMPACT
The Receiving and Filing of this report does not constitute a Fiscal Impact,however,the
programming level estimates for the two alternatives discussed range from $18.0 Million
to $19.2 Million.
CONCLUSION
The report establishes a clear and feasible method to manage drainage within the San
Ramon Canyon and the problems associated with erosion generated in RPV within the
canyon.The City Staff therefore recommends that:the City Council receive and File the
Project Study Report;and Set March 1,2011,during the regularly scheduled City
Council Meeting,as the date to conduct a Public Workshop for the San Ramon Canyon
Project Study Report.
Attachment:Project Study Report (see separate San Ramon Project Study Report binder)
Sketch of Alternatives
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