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HomeMy WebLinkAboutMINUTES - 08102010 - C.70RECOMMENDATION(S): AUTHORIZE the Shadow Creek Residents’ Association to conduct soil and road stabilization procedures for the down slope section of Bourne Lane within a deed restricted open space area of the Shadow Creek Manor project in the Danville/Tassajara area. FISCAL IMPACT: None. BACKGROUND: The affected project is the Shadow Creek Manor project, which is located between the Blackhawk and Bettencourt Ranch residential projects in the Danville/Tassajara area. The downhill side of a private road, Bourne Lane, and an adjoining open space parcel have recently experienced some slope failure. At the time the subdivision was established, the development rights over the open space parcel were conveyed to the County. The property is zoned Planned Unit (P-1) District. Around 2005, the area experienced slope failure and a similar slippage occurred. At that time, a development plan to allow proposed APPROVE OTHER RECOMMENDATION OF CNTY ADMINISTRATOR RECOMMENDATION OF BOARD COMMITTEE Action of Board On: 08/10/2010 APPROVED AS RECOMMENDED OTHER Clerks Notes: VOTE OF SUPERVISORS AYE:John Gioia, District I Supervisor Gayle B. Uilkema, District II Supervisor Mary N. Piepho, District III Supervisor Susan A. Bonilla, District IV Supervisor Federal D. Glover, District V Supervisor Contact: Tanner Humiston, 925-335-1202 I hereby certify that this is a true and correct copy of an action taken and entered on the minutes of the Board of Supervisors on the date shown. ATTESTED: August 10, 2010 David J. Twa, County Administrator and Clerk of the Board of Supervisors By: EMY L. SHARP, Deputy cc: Bob Drake, Ryan Hernandez, Tanner Humiston C.70 To:Board of Supervisors From:Catherine Kutsuris, Conservation & Development Director Date:August 10, 2010 Contra Costa County Subject:Authorize Road Stabilization Improvements within Deed Restricted Open Space of Shadow Creek Manor Project, in the Danville/Tassajara area. BACKGROUND: (CONT'D) repair and soil stabilization improvements, as recommended by a geotechnical consultant, was submitted to the County by the Residents’ Association and approved by the Zoning Administrator. The road was repaired and the County was not aware of any public controversy associated with these improvements. Recently, evidence of a new soil slippage affecting another section of Bourne Lane has surfaced approximately 50 feet north of the road repairs that were performed in 2005. Again the Residents’ Association retained a geotechnical consultant, Cal Engineering and Geology (CE&G), who performed an assessment and monitoring of the area. Through physical monitoring of the area, which consisted of drilling and sampling exploratory borings and analyzing changes in slope over time through the use of inclinometers, they determined that the slope had shifted significantly since readings taken at the same location on December 31, 2007. CE&G proposed using stabilization piers, a concrete waler (a bracket system), and tieback anchors for repairing the subject area. The CE&G report has been peer reviewed by the County Planning Geologist consultant. Bourne Lane is a cul-de-sac road (with a separate emergency vehicle only access on its west side) that serves a dozen residential lots. The repair work will require alterations that will temporarily narrow Bourne Lane to a one-lane road. The San Ramon Valley Regional Valley Fire Protection District has reviewed the plans and has no objection to them. No other nearby residential projects (e.g., Blackhawk, Bettencourt Ranch) will be affected by the proposed improvements. On July 7, 2010, the Zoning Administrator approved the application, File #DP10-3023, to amend the Shadow Creek Manor Final Development Plan to allow the proposed improvements subject to conditions. One of the conditions imposed on the project is that, prior to issuance of building and/or grading permits, the Board of Supervisors must authorize the proposed improvements within the deed-restricted open space parcel where the County holds development rights (i.e., scenic easement). CONSEQUENCE OF NEGATIVE ACTION: CHILDREN'S IMPACT STATEMENT: ATTACHMENTS Maps & Photographs DP10-3023 Findings and COAs approved by ZA on 7/7/2010 Geological Peer Review Project Plans