Controlled explosions might be loud in northern Morgan Hill

This story is based on a press release dated September 11, 2023

Photo courtesy Valley Water
The western end of the outlet tunnel on Anderson dam under construction. When complete it will be capable of releasing water 10 times faster than in the past.


Starting Sept. 12, 2023, construction crews working on the Anderson Dam Tunnel Project will begin the controlled blasting of hard rock to continue tunnel excavation. Over the next few weeks, scheduled contained detonations are expected to occur Monday through Friday and possibly on Saturdays between 8 a.m. and 7 p.m.

Residents residing within several hundred feet of the tunnel entrance site, located off Cochrane Road, may hear a series of short and long warning horn alarms before and after controlled blasts. These safety precautions are in place to protect construction crews and are similar to measures employed in residential and commercial areas for comparable public works projects. Trained personnel will oversee the detonations, ensuring the utmost safety with noise and vibration monitoring, storage, handling restrictions and additional precautionary measures.

The work on Valley Water’s Anderson Dam Tunnel Project, which began in May of 2021, is progressing as crews have since excavated nearly 775 feet of the 1,700-foot-long tunnel. This tunnel will provide greater control over reservoir water levels.

Valley Water remains committed to keeping the community informed about project developments. Regular updates will be shared through our NextdoorFacebook and website. Information can also be found on the City of Morgan Hill’s social media channels.

Valley Water is grateful for the community’s patience and understanding as we progress on this vital safety and water supply project.