Lagunitas Bridge Pipeline

North Marin Water District (District) supplies potable water to the West Marin area, including the towns of Point Reyes Station, Olema, Bear Valley, Inverness Park, and Paradise Ranch Estates.  The sole source of water conveyed to the latter four communities is via an 8-inch transmission pipeline that is connected to the bridge spanning Lagunitas Creek, a.k.a. the Green Bridge.

Because Caltrans plans to replace the Lagunitas Creek bridge beginning in 2026 (Bridge Project), the District will need to: install a temporary bypass pipeline spanning Lagunitas Creek; remove the pipeline connected to the existing bridge; and install a new pipeline on the newly replaced bridge.  The District and Caltrans are working closely to coordinate these items.

Starting in September 2025, the District will install new valving on each side of the bridge in preparation of the Bridge Project, and to accommodate the pipeline replacement work.

Prior to bridge removal, Caltrans will install a temporary casing spanning Lagunitas Creek that the District will use as a sleeve for the temporary pipeline to maintain water service to our customers during construction.

During the final stages of Caltrans’ Bridge Project, the District will install a new pipeline on the new bridge. The new pipeline will include seismic resilient expansion joints that will allow the pipeline to withstand ground movement caused by an earthquake. Additionally, the District will install bypass fittings on each side of the bridge to allow for connection of a temporary above ground pipeline should the permanent pipeline on the bridge be removed from service for any reason.