Napa River Watershed Gravel Augmentation Study
Cobble on alluvial fan on Ritchie Creek
The Napa River supports a run of Chinook salmon that spawn in the main channel. Like many creeks and rivers in California, the Napa River has an entrenched channel with high velocity storm flows. These conditions scour gravel from the river and limit spawning habitat. Many creeks in the Napa Valley are alluvial fans where they exit their canyons and course across the valley floor. An alluvial fan is mostly cobble, gravel, and sand with a number of different channels. Gravel may fill the creek channel, causing flooding and warranting removal of cobble and gravel.
The Fish Friendly Farming program is working with regulatory agencies and landowners on a number of alluvial fan creeks to devise a method to remove the cobble and gravel from creeks and place it in the river to increase Chinook salmon habitat. This project began in July 2008 and will require several years of study and permit negotiations before it can be implemented. Funding is provided by the Ecosystem Restoration Program of the CALFED Bay-Delta Program.
< back to index
>> Next project