Truth, Justice, and the American way. TRUTH: Helping to correct people's misconceptions about history, science, and the state of the world. JUSTICE: Meant in the biblical sense. Fair treatment of other people, rational laws, and assisting the disadvantaged. THE AMERICAN WAY: A classless society where everybody has an opportunity to meet their potential and for economic advancement, regardless of race, ancestry, religion, gender, or sexual orientation.

Saturday, May 23, 2015

Dealing with Droughts

California and 15 other states need more than water conservation to meet long-term water needs. Our state and local governments must make real changes to avoid severe problems. Drought years are natural throughout the US, but in the past few years, changes in Arctic ice make droughts more likely. For decades the US has been using well water beyond nature's capacity to replenish the aquifers (ground water). The increase in population and food exports just makes this worse.

States currently in multi-year droughts would require multi-year heavy rains to refill the reservoirs. All of the states West of the Rockies (except Hawaii) are currently in a drought. In California, where there have been 4 drought years in a row, the probability of a drought year next year is over 75%.

Severe water rationing may become necessary. This could include restricting tap water to certain hours of the day (like the rolling electrical blackouts a few years ago), reducing the pressure in water mains, elimination of all potable water for landscaping, and closing of businesses that do not recycle their water.

In California, severe water rationing has already hit agriculture. Farmers are not allowed to use water from rivers and reservoirs, so farmers are pumping from local wells. Some of the irrigation water sinks back into the aquifer, so it will be available for wells in the future. However, another drought year would empty many of the wells and severely reduce the US production of vegetables and cotton.

A proposal

 Starting immediately, all penalties for over-use of water should be used to increase the amount of water available.
To solve this long term problem, one needs a plan with a time-line and objectives. This proposal was submitted to the California State Resources Board and California governor several months ago.

Summer 2015, all processed sewage should be recycled. Water not used locally should be pumped to agricultural areas or used to recharge aquifers (pumped through plants and gravel into ground water). The cost is low, requiring that gravel-bottomed ponds (with recharge wells) be placed in overflow basins, and pumps and pipes to get the water there. Using the gravel, ponds, and plants ("Bio-filters") helps to purify the water before it enters the aquifer.

Spring 2016, excess recycled water should be made available for agricultural use. Possibly by pumping recycled water from cities for aquifer recharging in the Sacramento area. Most of this water would be pumped up-stream, so a large pipeline and pumps should be installed. Because most of this pipe would be installed next to the state's aqueducts, there would be no additional land costs and an emergency waiver of environmental impact reports would probably be approved. Water could be made available for environmental improvements to Owens Lake and the San Francisco Delta.

By the 2016-2017 rain season, the state's waste water processing plants should be expanded to handle the water from storm drains (rivers and washes). San Francisco and some other cities already do this. Untreated water from storm drains is a health hazard. This water could be added to the recycled water.

A long term improvement that might require a bond measure and federal funding is desalination of salt water (ocean water and agricultural runoff). Within 30 years, California should acquire 50% of its fresh water needs by desalination. A target of 10% by 2025 is reasonable.

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Canoga Park, California, United States
Software Engineer with Ph.D. in Computer Science. I have a deep background in the sciences and in computer-human interaction. I was a college professor for 11 years, followed by over a decade of work in industry.