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Our Opinion: Worth its salt?

August 25, 2001

The local proposal that could result in a million acre-feet of water being made available through reuse by the state's south coast cities sounds interesting.

The proposal belongs to the city of Brawley.

The idea is to reduce the quantity of total dissolved solids — salts — in Colorado River water from about 700 parts per million to about 100. The south state uses about 5.2 million acre-feet yearly of Colorado River water, though its legal apportionment is only 4.4 million. Water from the Colorado is blended with water from the State Water Project, reducing the TDS to about 550 ppm.

By the time the water is used by the consumer, and more salt is added, the water is likely available for reuse only once. If the water were reduced in TDSs before it reaches the municipalities that use it, the water likely could be reused as many as three times. It could be reused in industry, agriculture and put back into the ground for withdrawal later as fresh water.

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Using Brawley's estimates, there could be as much as a million acre-feet of new water available for reuse by desalting river water. There would, of course, have to be investments in wastewater recovery and treatment made by the cities and agencies that lie on the coast to take advantage of the less salty water.

The proposal differs from San Diego's failed "toilet-to-tap" idea in that no one is proposing treated wastewater be sent back to anyone's tap for human consumption.

The proposal suggests the $600 million desalinization plant be built by the Metropolitan Water District of Southern California, a cooperative of 26 cities and water agencies serving 17 million people in six counties. The desalted water would be equal the entire yearly flow of MWD's Colorado River Aqueduct, or about 1.4 million acre-feet.

Besides the cost to build, operate and maintain the desalting plant, there would be a yearly loss of about 60,000 acre-feet to a waste stream from the plant.

Sixty-thousand acre-feet is a lot of water by today's standards.

Under the proposal, the waste stream would flow down hill 2,000 vertical feet and be the motive force behind the generation of 8 megawatts of electricity. That power would be sold on the open market, with proceeds of about $1 million yearly going to the city of Brawley.

That's a lot of money.

In exchange, the city of Brawley is lending its name as a municipality to lock up the idea before the Federal Energy Regulatory Commission. The city is making token contributions not expected to exceed $50,000.

One million dollars a year on a $50,000 investment is a pretty good return in anybody's book.

If it comes true.

There are a number of questions, however.

One is, where is Brawley going to find someone to invest in the power plant?

What will be the cost to clean up the salty wastewater — expected to have as much as 12,000 ppm TDS — after it drives the power turbine and flows into the Salton Sea.

Does anybody really expect the Coachella Valley Water District to allow 60,000 acre-feet of such water to flow down its wasteway when in today's litigious society it could be held financially responsible for its effects?

If the water does make it into the Salton Sea, what are the costs to reduce its effects on the sea's ecology and to eventually clean it up?

Despite the questions, and many other we could never think of, the idea still remains interesting, and we are sure we will hear much about it in the future.

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