Fixing the Sacramento River Delta

Thanks to Follower Mic for sending along this link about a month ago: http://www.businessweek.com/ap/financialnews/D9FBLI101.htm
The Sacramento River Delta is the largest river delta on the west coast of the United States. It is remarkable for many things, including its unique location — it’s not on the coast! The Delta is almost in the middle of the state of California, set several miles away from the Pacific Ocean, with the sprawling San Francisco Bay in between.
Technically, San Francisco Bay is part of the Pacific Ocean, and it has the salt water environment to prove it. In this photo, we see the interface between the Delta and the Bay. But where does one end and the other begin?
To answer that question, we rely on one of our old adages: Water flows downhill.
The important line of delineation between the Bay and the Delta is where fresh water meets salt water. And this location changes, based on two key factors: the level of the ocean and the level of the fresh water. The true boundary is the point at which these two elevations are the same.
The height of the oceans has been subject of much speculation of late, courtesy the global warming controversy. “Warmists” contend that higher Earth temperatures will cause permanent ice, notably the polar ice caps, to melt into the oceans, causing sea level to rise. Al Gore estimated that the rise could exceed 20 feet. In the case of the Delta, that would push the boundary of the Bay all the way to Sacramento and beyond, and thus totally transform this aquatic ecosystem into a marine one — and completely decimate California’s State Water Project. “Deniers” like me remain concerned, but don’t link fossil fuel combustion and capitalism to ecological cataclysms such as this. Other threats to our system seem far more likely.
But there is no controversy over ocean tides. You can easily access tide tables that predict, with uncanny accuracy, the level of the ocean at different locations and times. The important thing here is that the level of the ocean changes — by several feet — on a normal basis. And increases in sea level push the Bay farther into the Delta.
And what of the fresh water level? During late Winter and Spring, high outflows from the tributaries to the Delta raise the water level, and thus push the boundary towards the Bay. And during low flow periods, such as droughts, the fresh water level declines, allowing the Bay to move farther east into the Delta.
Pumping fresh water out of the Delta also causes a decline in the fresh water level. So our water system operations definitely impact the Bay-Delta boundary.
Not knowing where the boundary is or will be presents water system managers with a huge operational challenge. Failure to locate the boundary would lead to sea water entering drinking water and irrigation systems throughout the State — now that’s an environmental disaster!
What tools do our water managers have to deal with this reality? First and foremost: monitoring. A team of professionals is at this every single day, to minimize the intrusion of sea water into drinking water. But today, that’s really their only tool. Pumping from the Delta is increased or decreased in response to the monitoring results — and in response to other environmental concerns.
Almost everyone agrees that this situation is poor for the environment, for water quality, and for water supply. And almost everyone also agrees on the solution: don’t pump from the Delta; pump from the higher elevation of the Sacramento River before it enters the Delta. This will require the Peripheral Canal. The article today is just one more example of how difficult it will be to implement the best solution to this problem. Will our politicians allow the Canal to be built, or will California suffer unimaginable damage for generations to come, once the Bay-Delta interface overruns our pumping systems, when the sea flows downhill into our water supply?

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