HomeMy WebLinkAbout04/15/2008, C5 - ANDREWS CREEK BYPASS, SPECIFICATION NUMBER 90562 a
council MemnsDa 4/15/08
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CITY O F SAN LUIS O B 1 S P 0
FROM: Jay Walter,Public Works Director
Prepared By: Matt Hom, Supervising Civil Engineer
SUBJECT: ANDREWS CREEK BYPASS,SPECIFICATION NUMBER 90562
CAO RECOMMENDATIONS
1. Approve a purchase order in the amount of$55,113 with the Wallace Group for alternatives
analysis for the "Andrews Creek Bypass, Specification Number 90562".
2. Approve a transfer of $60,625 ($58,783 from construction and $1,842 from study) to the
design account for this project.
DISCUSSION
Backaround
In 1999 the Andrews Creek Bypass Project was constructed. The goal of this project was to
reduce flooding of Conejo Avenue. This project installed a high flow bypass system that could
allow larger flows in Andrews Creek to be diverted into two pipes, going down Andrews Street,
and into San Luis Obispo Creek.
Prior to 2005, fill material had been placed in the creek bed upstream from the Andrews Creek
bypass structure to facilitate equipment crossing. Around New Years 2005, a significant
rainstorm occurred in our area. This creek crossing fill material became saturated during the
storm, broke loose and flowed down the channel filling up the bypass structure. This caused
water, that would have normally entered the bypass structure to flow further downstream in
Andrews Creek, to travel outside of the channel and into the garage of a residence on Conejo
Street. Litigation ensued as a result and remains pending.
City staff evaluated the bypass structure and concluded that modifications could be made to
improve reliability. A non-specific CIP project was included in the 2007-09 Financial Plan and
preliminary design work began in May 2007. City staff, in response to the pending litigation, is
also considering a flood wall and swale through the drainage easement.
Alternatives Analysis
Staff requested a proposal from the Wallace Group to evaluate this area and complete hydrologic
and hydraulic analysis of the entire area, including the natural channel, existing catchments, and
the flood wall and drainage Swale concept. Additionally, staff requested Wallace Group provide
other unconsidered alternatives that might address concerns of area residents.
The scope of Wallace Group's work is to: 1) analyze the conditions of the existing watershed and
the current level of flood protection; 2) develop several conceptual alternatives for improvements
intended to provide 100-year flood projection for all at-risk properties in the area; 3) attend
meetings with project stakeholders to help facilitate selection of a preferred alternative; and 4)
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Report Title Page 2
develop a preliminary design and cost estimate for the preferred alternative to be used as a basis
for future funding authorizations.
FISCAL IMPACT
This project was approved in 2007-09 Financial Plan (refer to pages 3-284 through 3-286,
Appendix B). The project budget allows for $15,000 for Environmental Review, $15,000 for
Design Services and $100,000 for Construction funding. Previous project expenditures for
engineering and survey services have required$28,158 of this funding.
As part of the City's effort to utilize Measure Y revenues, three pre-qualified design consultants
were selected and agreements awarded in late 2007. Each of the pre-qualified design consultants
were selected for their defining areas of expertise. Wallace Group was one of the pre-qualified
design consultants and has the expertise to be of value for this specialized type of work.
The Wallace Group's proposal of $55,113 will require the transfer of funds, in the amount of
$58,783 from the construction account and $1,842 from the study account to the design account
for this project. The need for additional funding of future design and construction services will
be addressed once Wallace Group's alternatives analysis is complete and a preferred alternative
has been selected.
Project Budget Proposal Costs
Study $ 15,000 Wallace Proposal Amount $ 55,113
Design $ 15,000 Contingencies $ 5,512
Construction $ 100,000 Wallace Group Total $ 60,625
Total $ 130,000
Remaining Project Funding $ 41,217
Previous Costs $ 28,158
Remaining Funds $ 101,842
ATTACHMENT
Location Map
G:\Staff-Reports-Agendas-Minutes\_CAR\2008\CP\90562 Andrews Bypass\90562 Award Design PO.doc
ATTACHMENT 1
Location Map
Andrews Creek
Bypass Structure
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