HomeMy WebLinkAbout05/19/1998, C5 - APPROVAL OF REPAIRS FOR RETAINING WALLS AT SYLVIA COURT council M ►q , A4 G
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CITY O F SAN LUIS O B I S P O
FROM: John Moss,Utilities Director/,"'
Prepared by: Dan Gilmore,Utilities Engin
SUBJECT: APPROVAL OF REPAIRS FOR RETAINING WALLS AT SYLVIA COURT
CAO RECOMMENDATION
Authorize the CAO to approve the following actions:
1. Negotiation and execution of a consultant services contract for design of the retaining
wall repairs,
2. Approval of final plans and specifications and authorizationfor solicitationof bids,
3. Award of construction contract to lowest qualified bidder,and
4. Transfer of needed funds to pay for construction work,up to a total authorized fimding
level of$250,000.
DISCUSSION
Background
On Friday, January 23, 1998, the City's 16-inch high-pressure waterline serving the Terrace Hill
Tank ruptured. On February 6, 1998,two retaining walls behind properties on Sylvia Court failed.
Staff subsequently contacted a local geotechnical firm to survey the site and provide
recommendations for temporary measures to stabilize the area. Plastic sheeting was installed over
the entire slope area above the failed wall to reduce additional water entering the slide and
minimize the potential for additional soil movement.
Following the implementation of measures to prevent additional damage to the residences, staff
requested the geotechnical firm Earth Systems to prepare a written summary of their survey and
their conclusions relative to the cause of the slope and retaining wall failures in the area.. In short,
their opinion is that the slope failure was not a result of the broken waterline. The time period
between the pipeline break and the wall failures was too long,and the distance from the break to the
wall failure location too great to have been the result of the pipeline failure. While the geotechnical
consultant has provided good reasoning that the City is not responsible for the retaining wall
failures, it is recognized that other experts could argue that the pipeline break contributed to the
wall failure. At a Closed Session on May 5, 1998,Council determined that it is in the best interest
of the City to perform these needed repairs in cooperation with the affected property owners.
Proposed Project Schedule
The goal for the project would be to complete construction work prior to next winter. This means
that the project schedule should be developed to complete construction by November. Due to the
short period of time available to complete the necessary design and construction, staff is asking
Council to authorize the CAO to approve all aspects of the project The following schedule has
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Council Agenda Report-Approval of Repairs for.Retaining Walls at Sylvia Court
Page 2
been developed to guide progress and ensure completion of the retaining wall repairs prior to the
next rainy season.
SCHEDULE
Items/Tasks Dates
1. Council approves "fast tracking" project, authorizes CAO to award May 19
contracts for design and construction
2. Award design contract May 25
3. Preparation of plans and specifications June-July
4. Advertise for bids August 1
5. Bid opening August 17
6. CAO awards contract August 19
7. Begin constriction September 2
8. Complete construction November 16
The schedule identified above is very aggressive and will require that normal procedures for
initiating and completing construction of a project of this type be modified. If the Council concurs
with the CAO recommendations,staff will negotiate with several local engineering firms for the
preparation of plans and specifications and the City Administrative Officer will approve the
contract for consultant services,approve plans and specifications and request for bids,and award of
contract to the lowest responsible bidder. The requested modifications to normal City procedures
are necessary to complete the wall construction before next winter.
CONCURRENCES:
The City Attorney and the Risk Manager both concur with the recommended actions.
FISCAL E%IPACT:
The cost of repairing the retaining wall damage is estimated to cost up to $200,000. Design of the
repair work is estimated at $30,000. At the appropriate time, staff will ask the CAO to approve
transfer of the necessary monies from Water Fund balance to the associated project account.
Adequate working capital is available to fund the proposed project and retain balances within
minimum policy levels. There will be no impact to the Operating Budget
ALTERNATIVES:
Defer the project to follow standard procedures. This is not recommended, since any delay
would likely result in failure to make the necessary repairs prior to the onset of the next rainy
season. This could cause additional damage and may expose the City to increased liability.
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