Despite heavy rains and challenging conditions, the Alameda Siphon #4 Project team completed its work on the Sunol Valley side of the Coast Range Tunnel during the winter shutdown ahead of schedule.

The contractor – Steve P. Rados, Inc., worked round the clock to install a new manifold, a new bulkhead, and new connections to the three existing siphons and future siphon #4.  This work had to be done when the tunnel was empty of water.  Not only did crews have to work 20 hours a day in wet and muddy conditions, they had to run large specially-made fans to ventilate the tunnel of the naturally occurring methane gas that seeps into the tunnel when it is empty.  The team took all necessary precautions to ensure the safety of workers and the public throughout this period.

The Coast Range Tunnel is expected to be back in service on February 14th. 

The Alameda Siphon No. 4 Project extends approximately 3,000 feet from the Alameda East Portal across both the Calaveras Fault and Alameda Creek to the Alameda West Portal.

The proposed project would consist of: