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HomeMy WebLinkAboutMINUTES - 05051987 - 2.8 00S TO: BOARD OF SUPERVISORS, as the Governing Board of the Contra Costa County Flood Control and Water Conservation District. FROM: J. MICHAEL WALFORD, CHIEF ENGINEER DATE: April 28, 1987 SUBJECT: Wildcat and San Pablo Creeks Specific Requests or Recommendations & Background & Justification I. RECOMMENDED ACTION: A. ACKNOWLEDGE receipt of report from Wildcat and San Pablo Creeks Project Design Team indicating their preference for a trapezoidal rock channel section on Wildcat Creek between the railroad tracks. B. ACKNOWLEDGE receipt of report from Wildcat-San Pablo Advisory Committee recommending the gabion-walled, concrete bottom section unless additional funding can be identified for the trapezoidal rock channel . C. ACKNOWLEDGE receipt of letters stating positions for preferred a 1 terna te. D. ADOPT recommendation of the Flood Control District for a gabion-walled, concrete bottom, channel section for Wildcat Creek between the railroad tracks. E. ADOPT additional environmental enhancements to the Consensus Plan downstream of the railroad tracks on Wildcat and San Pablo Creeks. II. FINANCIAL IMPACT: Selection . of the rock-lined channel section between the railroad tracks on Wildcat Creek will require an additional local cost of $115 ,000.00 plus an additional annual maintenance cost of $3,500.00 over the gabion-walled, concrete bottom channel alternate. The Flood Control District does not have the funds for these additional costs. The current environmental enhancements have caused the project cost to go beyond current project 'funding. Continued on attachment: X yes Signature: ,J Recommendation of County Administrator Recommendation of Board Committee Approve Other: Signature(s) : Action of Board on: May 5, 1987 Approved as Recommended Other x DEFERRED decision to May 12, 1987 on channel section on Wildcat Creek between :the railroad tracks; and REFERRED to. the County Administrator. for recommendations relating to financing of the trapezoidal rock channel endorsed by the 'Wildcat/San -Pablo Design Team. Vote of Supervisors I HEREBY CERTIFY THAT THIS IS A TRUE AND CORRECT COPY OF AN ACTION TAKEN x Unanimous (Absent — ) AND ENTERED ON THE MINUTES OF THE Ayes: Noes: BOARD OF SUPERVISORS ON DATE SHOWN. Absent: Abstain: Attested Orig. Div.: Public Works (Design) Phil B c e r Clerk of the Board of Supervisors cc: County Administrator and County Administrator Auditor-Controller PW Accounting By Deputy Clerk PMc :bb bo:d.28.t4 III. REASONS FOR RECOMMENDATION/BACKGROUND: Cont'd. The Board of Supervisors originally adopted the Corps Selected Plan in February, 1985 . At that time the Design Team began to incorporate innovative ideas in the design of the project in order to meet the community's need for affordable and environmentally sensitive flood control . The Design Team developed a Consensus Plan which did meet community and environmental needs and was adopted by the Board of Supervisors in December, 1985. The Consensus Plan assumed that outside agencies would make firm commitments of adequate funding. The agencies involved with the Design Team have provided some addi- tional local funds. The State Land Commission purchased a piece of property for the project and additional enhancement. The Coastal Conservancy has approved a grant which includes funding for some project construction and land costs, however these funds are princi- pally for enhancements above and beyond the Consensus Plan. Flood Control District staff is working with the Coastal Conservancy to reach an agreement on the conditions for these funds. The East Bay Regional Park District (EBRPD) has indicated that they have funds for right-of- way purchase in connection with the project. However, they have not made a determination on what they will purchase. Even with the addition of the above funds, the District still expects to have a local fund shortfall of $300,000. We have reviewed the funding issue with the County Administrator ' s office and Special District Augmenta- tion fund money is not available. The Consensus Plan included a gabion-lined channel on Wildcat Creek from Verde School through the railroad tracks. The Army Corps of Engineers is currently completing their hydraulic analysis on this section of Wildcat Creek. However, the Corps has recommended a rock- lined trapezoidal channel in place of the gabion lining through the Verde School reach. The Design Team supports this modification. There was extensive discussion with the Design Team on the proposed channel section between the railroad tracks. Three alternatives were considered. The first alternative, which is supported by the Flood Control District staff, is a gabion-walled, concrete bottom channel section. The concrete bottom channel can be maintained from the bottom, therefore reducing the right-of-way required and also elimi- nating the need to have overland access through an industrial business site. The second alternate is a rectangular concrete channel . The Design Team and the District eliminated this alternative from consider- ation. The third alternative which is supported by the Design Team is a rock channel section. The Corps of Engineers had indicated that they expect some sedimentation in this section of the creek. The District is concerned about the additional cost to maintain and remove sediment from the rock-lined channel . Because of the width of the channel , access roads will be necessary on both sides. Also, approximately 1 ,000 LF of easement through the business to the south would be necessary to reach the channel . The Flood Control District does not have the funds for the wider right-of-way, longer bridge crossing and access easement required for the rock channel alternate. The rock channel would also have a higher yearly maintenance cost. All three alternatives are acceptable to the Corps of Engineers. Since the Design Team and Flood Control District cannot reach consensus on this issue, it has been brought to the Board for resolution. The Army Corps of Engineers has requested that we advise them of our preferred alternative so that they may proceed with their design. Additional changes have been made to the Consensus Plan for which we would like the Board's concurrence. They are as follows: 1 . The siltation basin originally planned for 3rd Street on Wildcat Creek is to be relocated to property purchased by the Flood Control District at 7th Street immediately downstream of the railroad tracks. 2. The section of channel from 3rd Street to Verde School will be an earth channel similar to the channel section downstream of 3rd Street. 3. The channel section through the Verde School property will be rock-lined instead of gabion-lined. 4. The Design Team requested additional enhancement in the Wildcat Creek marsh area. If the funding agreement with the Coastal Conservancy is worked out for this revision, the District will request the Corps to modify their plan. IV. CONSEQUENCES OF NEGATIVE ACTION. The District supports the above modifications and recommends the Board concur with them. Failure to select an alternative for the channel section on Wildcat Creek between the railroad tracks will place the Wildcat and San Pablo Creeks Contract 2 on hold until a selection is made.