Case Study: Napa Salt Ponds and Federal Oversight of the Bay

Aerial photos of the Napa salt ponds
Aerial photos before and after the levees were breached at the former Cargill salt ponds in the Napa River (Google Earth). Future public access opportunities will include walking trails, fishing, kayaking, and more.

After Cargill and developer DMB’s sudden withdrawal last May of their initial proposal to pave over San Francisco Bay salt ponds in Redwood City, the companies have been busy lobbying federal agencies to exempt the below-sea-level ponds from important environmental regulations that protect the Bay from being filled. Cargill/DMB’s stated intention is to bring back another proposal to put thousands of houses on this 1,400-acre restorable site.

We have written in the past about Cargill’s flawed arguments for why they think the Clean Water Act doesn’t apply to them. (See “Cargill’s 370-Page Attack on the Bay,” Part I and Part II) Another key reason the Army Corps of Engineers and the Environmental Protection Agency should ensure federal oversight over the Redwood City salt ponds is the fact that these agencies have a long-history of asserting jurisdiction over San Francisco Bay salt ponds, including ponds nearly identical to those in Redwood City.

Exhibit A is the Former Salt Ponds along the Napa River in the North Bay

Now being restored back to wetlands and abundant with wildlife, Cargill’s former salt ponds along the Napa River are now known as the “Green Island Unit.” Like Redwood City’s ponds, they were former Bay marshes, diked off for salt making over 50 years ago and used by Cargill as “crystallizers” for the saltiest part of the salt production process.

Cargill sold the Napa ponds to the State in 2003 so they could be restored back to marshes. Thanks to federal stimulus funds and the support of generous private foundations, the levees have since been breached, the site connected back to the Bay tides, and if you visit the area now, it’s nearly impossible to determine where the Napa River ends and the former salt ponds begin. It’s all flooded with water.

In a submission to regulatory agencies in 1996, before Cargill sold the site, the company gave similar assertions to federal agencies about why the Napa ponds should not be governed under the Clean Water Act. Cargill claimed that the millions of gallons of water pumped from the Bay into the salt ponds was not water at all and that the Napa salt ponds are a “highly manipulated industrial facility” supporting “little to no biological activity,” despite their use by migratory shorebirds. (Sound familiar? See “Cargill Misleads Gov’t Agencies about Salt Pond Wildlife“)

100% “Waters of the United States”

When federal agencies finally decided on the jurisdictional status of the Napa salt ponds, the results were clear: As below sea-level, diked off tidal waters adjacent to and formerly part of the Napa River, the Napa salt ponds are entirely “waters of the United States,” wrote the Army Corps of Engineers in 2008.

Despite Cargill’s repeated claims to the opposite, the Army Corps ruled that the Napa salt ponds are unequivocally subject to the important federal environmental rules enshrined in the Clean Water Act and the Rivers and Harbors Act. If anyone wanted to fill these ponds, they would have to get a permit from federal agencies first.

Will the Army Corps follow this strong precedent and continue to assert jurisdiction over the Bay’s salt ponds – this time in Redwood City? We’ll find out soon.

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