Sites Reservoir: New Water North of the Delta

Zone 7 is one of 24 public water agencies participating in Sites Reservoir, a new off-stream storage facility planned for Colusa County, north of the Sacramento–San Joaquin Delta.

The numbers from the newly adopted Capital Improvement Plan: Zone 7's share is $208 million in capital costs, with a total obligation of $553 million over 46 years. The total project cost across all participants is approximately $7.5 billion. Construction is expected to begin in 2027, with the reservoir operational by 2034.

Why Sites matters for the Tri-Valley

Sites Reservoir is located north of the Delta. That means the water it stores does not depend on Delta conveyance infrastructure to reach Zone 7's system. In a world where the State Water Project delivers just 54% of contractual allocations and that number is declining, having a supply source that routes around the Delta's vulnerabilities is a meaningful hedge.

It's also a portfolio play. Zone 7's water strategy isn't a bet on any single project — it's a combination of local groundwater management, Chain of Lakes storage, state deliveries, and new regional sources. Sites Reservoir fills the "new regional source" slot in that portfolio.

The construction decision

The construction participation decision is expected this year — 2026. That means the current board, and potentially the next one, will be weighing in on a $208 million capital commitment.

These are exactly the decisions that drew me to this race. A $208 million investment in a multi-agency reservoir requires the same kind of engineering due diligence and financial oversight that I've practiced at the board level for the past decade. What's the cost risk if construction overruns? What's the delivery timeline risk? What happens if other participating agencies scale back?

Zone 7's staff has been doing this analysis. A board member's job is to ask the right questions and make sure the answers hold up.