This past weekend before heading off on a short hike at Henry Coe State Park I checked the park's website for a map. On the front page there was a notice about the Santa Clara Water District's proposal to build a dam in or about the park. A summary of the proposed dams can be found here. The proposed Coe Reservoir looks like it would have the biggest impact on the park. From the website:

The Coe Reservoir (referred to by some as The China Hole Dam), with a dam a short distance downstream of China Hole. The dam would back water up the East Fork of the Coyote Creek for about seven miles, up the Middle Fork about four miles, up Kelly Cabin Canyon about four miles, and up the Little Fork, Rock House Canyon, Little Long Canyon, Water Gulch, and other drainages for varying distances.