Friday, February 27, 2009

Westward Ho: A Water Transfer System

It is becoming more and more apparent that the U.S. must transfer some of the excess water that floods the Mid-Western states to the dry Western states. My colleagues and I have been researching this for several years, and have some ideas. We conclude that it is in the national interest to do, and should be a no-brainer.  

Ancient civilizations realized the critical need for water, and did what it took to move the water to where it was needed. The Romans of course built their famous aqueducts, and the ancient Chinese routed water also. Many others did, too.  

While the current Presidential administration is passing out money as if it grew on Sequoia trees, this is a project that should be on the list. 

California has an extensive history with water projects, with routing water from the Sacramento River south to Los Angeles, from the Owens Lake area to Los Angeles, and more recently the Colorado River to Los Angeles and San Diego. However, none of these is adequate given the growing California population, droughts, and decreased snow in the Sierra Nevada Mountains.  

An amazing fact is that water pumps consume approximately 10 percent of all the power sold in California. Some of that is recovered as hydroelectric power.  The recovery of power from water factors in this.

One possibility on the national level is a water transfer system from the Missouri River at Kansas City, that runs approximately 800 miles southwest to the continental divide in New Mexico, just south of Interstate 40. From there the water would flow into tributaries of the Colorado River. The hydroelectric plants are already in place on Hoover Dam and Glen Canyon Dam. Therefore, some of the power expended to pump the water uphill and 800 miles would be recovered. The elevation change is on the order of 6,000 feet.  

The water route will be through the U.S.' great wind corridor, so it is conceivable to use windmills to provide energy to the pumps. How the water is transferred is of course an engineering problem, one solution is to use a buried pipeline, or build a series of open canals with a slight downward slope to the southwest, and install water lift (pumping) stations at regular intervals. Something of the same magnitude was done by the construction of the Erie Canal in New York, which runs approximately 365 miles, and 600 feet uphill. It took 8 years to build and was finished in 1825.  

This is the type of project that has enormous benefits for almost all Americans, and would certainly be less expensive than building and operating desalination plants using reverse osmosis. The existing lakes Mead and Powell could store the water as necessary. One benefit is an assured supply of agricultural products from the fertile but arid California farmlands and dairies. California supplies a large part of the nation's foods, when there is adequate water.

An advantage of the buried pipeline alternative is no water loss due to evaporation, but a disadvantage is higher initial cost, and higher pumping costs due to friction as the water flows through the pipe.

An advantage of the open canal design is lower pumping cost, but a disadvantage is slight water losses due to evaporation.

The amount of power required to pump the water is tremendous, at roughly 800,000 HP for a flow of 1,000 cubic feet per second.

Given a simple design of 800 miles broken up into 10 mile sections of canal, with a pump at each section, would require 80 pumping stations at 10,000 HP each. The 10,000 HP is roughly 7.5 MW of energy. Of course, an actual design would follow the contour of the land and have pumps sized appropriately for each section. Even if all 80 pumping stations are built, the amount of power required is approximately 600 MW.

The Missouri River flow varies of course, but is somewhat regulated by a series of flood-control dams upstream. The USGS shows the typical flow is about 4,000 to 5,000 cubic feet per second. Therefore, diverting 1,000 cubic feet per second would not likely be a problem. Diverting twice that amount, or three times that amount, could conceivably cause problems.

This would be a job for the Army Corps of Engineers, and is a worthy challenge to their expertise.

Addendum: I added a second piece to this at Wind, Water, Farms and Power Generation.

Roger E. Sowell, Esq. Legal website is here.

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