Matt Weiser June 9 2017 Water Deeply see full article here
A newly certified carbon trading protocol could help solve a number of problems in the West’s largest estuary, including flood risk, water pollution, habitat loss and threats to a critical freshwater supply.
…The largest estuary on the West Coast of the Americas, the Delta is a network of some 70 islands protected by more than 1,000 miles of levees. The soil on these islands is some of the richest farmland in the world because it is composed of organic material: decaying plants that accumulated over millennia.
But when the levees were built 150 years ago to create farms, this dried out the soil, causing it to oxidize and decompose. As a result, the surface of many islands has slowly sunk below sea level. This results in a stronger leverage force on the levees, making them more vulnerable to failure. That’s a problem because the Delta is also the source of freshwater for 25 million Californians and more than 3 million acres of farmland. If numerous islands flooded due to levee failures, seawater could rush into the estuary and compromise the freshwater supply…
Campbell Ingram: For every inch of elevation that you don’t lose in a given year due to ongoing agricultural practices, you’re not increasing hydrologic pressure on the levee. And for every inch that you then accrete in elevation, you’re reducing that pressure. It’s a slow process, but it’s at least moving in the right direction.
A wetland compared to a monoculture of corn is typically going to have higher biodiversity, more use by waterfowl and amphibians and giant garter snakes. You can have some water quality benefits. And obviously the greenhouse gas emissions reduction and subsidence reversal….
…The Air Resources Board recently put out their latest scoping plan, and in that they describe a target of 15,000 to 30,000 acres of managed wetlands in the Delta in the next 13 years. This is one of the best uses of the western Delta because of its importance to the water supply….