Ross Valley Sanitary District

Start Date: June 2, 2010

Project Description: The Kentfield Force Main (KFM) project will replace a large sewer pipe running along Corte Madera Creek and down South Eliseo Drive.  The upgrade to this vital link in our collection system serving about 60% of our customers will increase capacity, reliability and address seismic concerns. 

Segment 1

June 21, 2010 – Work began to upgrade/repair a 30-inch gravity pipe that will handle wastewater flows that will be diverted from the old force main while repair work is done. The pipe will be used in conjunction with new forced main once it is completed to significantly increase the reliability and capacity of the system. The pipe was first hydro-cleaned to prepare it for upgrading.

July 16, 2010 – With the gravity pipe clean, a new liner was installed using Cured In Place Pipe technology (CIPP). This upgrade renders the pipe as good as new.

August 2, 2010 – Wastewater collection flows are diverted from the existing KFM to the newly repaired/upgraded gravity pipe and the old KFM is then drained to avoid spills during repair.

August 2, 2010 – The first section of the KFM to be replaced runs from the east end South Eliseo Drive (by the bike path) to the west end of Corte Real. The old 36” pipe is replaced by a new HDPE 42” main.

September 1, 2010 – Grout injection stabilization of the berm begins.  Please note that for your protection, the path will be closed for the next couple of months.  Pedestrian and bike traffic will be detoured to the path north of Creekside Park to Sir Francis Drake Blvd.

October 15, 2010 – With the new force main installed along South Eliseo, wastewater flow is restored to both the old and new sections of the KFM to accommodate heavy demand during the winter months. Stabilization work on the berm running along Corte Madera Creek is completed in preparation for Segment 2 of the KFM Project that begins next spring. 

December 15, 2010 – Grout injection projected to be complete.  Segment 1A construction projected to be complete.

Segment 2

July 5 2011 – Work resumes on the KFM Project and the section of the main that runs from the Bon Air bridge along Corte Madera Creek to the pump station near Stadium Way and across from Kent Middle School is upgraded.

October 15 2011 - With the force main pipeline installed in the berm and reconnected to the pump station and the recently-installed Segment 1A of force main, wastewater flow is restored to the KFM to accommodate winter flows.

December 15 2011 – KFM Project is complete. Project area restored and pathway reopened.

Public Outreach Notification

Detour Map

Start Date: October 2011

Project Description: The William/Holcomb/Meadowood CIP – Phase 2 (WHM Ph 2) project will redirect flow through a new gravity sewer creek crossing and eliminate a sewer siphon which has been a known maintenance issue. The project includes construction of approximately 65 feet of gravity sewer under Larkspur Creek to replace the existing siphon and approximately 695 feet of pipeline on the south side of the creek in an existing dirt pathway trail between Meadowood Drive and Heatherwood Park. Open trench methods will be used to install the new 12-inch PVC C900 sanitary sewer pipeline and connect it to the existing 18-inch diameter pipeline on the north side of the creek.

October 11, 2011 – The dirt pathway along Larkspur Creek is closed between Meadowood Drive and Heatherwood Park.

October 15, 2011 – The new Larkspur Creek crossing work is completed.

October 31, 2011 – The installation of new pipeline along the dirt pathway is completed and the path is reopened.

November 2011 – WHM Ph 2 Project is complete.