Article courtesy of Ben Adler | Feb 12, 2016 | The Energy Collective | Shared as educational material
What if there was an abundant source of pure water under the desert sands? As it turns out, there is. Beneath the scorched earth of a western desert lies a supply of water greater than that contained in North America’s Lake Mead. The problem is that much of this water is either inaccessible, unusable, or is being lost to evaporation. The severity of long-term drought in southern California has brought water utilities and private investors together to solve the problem. There are many efforts underway, aimed at diverting, storing and conserving billions of gallons of water for use now, and in the future.
Where the Water Comes From
When rain and snow fall in the mountains, gravity forces it to run downhill, forming a watershed. As the water soaks into the earth, it moves downward through soil and layers of rock, which filter it along the way. Ultimately, it forms an underground aquifer system of tributaries, streams and rivers.
Where the Water Goes
Over time, and depending on the amount of precipitation flowing down through the watershed, water bubbles back up to the surface, filling shallow lakes in the desert. The water evaporates quickly in the heat of surface temperatures, leaving minerals and salts behind. The small amount of “hard” water left is too salty for irrigation, drinking or bathing.
So much water loss from evaporation is unacceptable during a time of historic drought. Planned water conservation efforts are necessary to better manage this essential natural resource in a sustainable and environmentally conscious way. Rather than importing fresh water from overburdened reservoirs, rivers and aqueducts, the goal of such projects is to divert water and store it underground before it can reach the surface and be lost to evaporation.
About Cadiz Water Project – a Two-Phase Plan for Implementation
This particular project provides a good example of a water conservation effort, in two phases. Phase I involves building a system of wells that will tap into the aquifer system in previously developed areas of the Cadiz Valley. Building such a system on a farm or other private land minimizes the project’s footprint and impact on the desert ecosystem. A 43-mile pipeline, running along an established railroad line will connect the wells to the Colorado River aqueduct and water can be transferred, if needed, to southern California and other drought-stricken areas.
A limited amount of water can be withdrawn locally, without harming the aquifer’s integrity or ability to refill. It is estimated that the water needs of about 400,000 people can be served annually this way, over a 50-year project lifetime.
Phase II will involve adding infrastructure for capacity and storage of groundwater, increasing supply during times of drought and replenishing the aquifer when necessary.
Benefits of Planned Water Conservation and Management
Such projects provide numerous benefits for the community and the environment in particular and southern Californians in general.
First, the environmental benefits are clear. In a drought, groundwater is pumped from aquifers at an alarming rate. When the aquifer is empty, it collapses like an underground tunnel or mineshaft, and the land above sinks to fill the empty space. Controlling, diverting and collecting groundwater will help prevent this growing problem.
For people all over southern California, having a ready and reliable supply of water on hand can reduce or at least stabilize water rates. It also reduces the need to import water from the Colorado River Aqueduct, which is already highly overused and increasingly regulated.
There are also economic benefits, with the short- and long-term employment that project construction and management brings. Additional savings are generated over time, and can rise into billions of dollars.
A Good Idea Whose Time Has Come
So far, questions about water projects such as have been numerous, but they are answerable, and obstacles can been addressed, one by one. Testing of the water table and soils of ensures that water is free of chromium, heavy metals and pollutants. Dust and particulate pollution from construction can be projected and monitored for safety. Finally, because projects can be developed on private land, there is no conflict with federal land conservation efforts in the region.
California’s years of drought have been so severe that even the strong El Nino of 2015-16 will not make more than a small dent in its overall water shortage. Because the state is economically dependent on agriculture, water must continue to come from somewhere. As it turns out, a tremendous supply of water has been right under the feet of the people of southern California all along. Careful stewardship and care of this precious resource will ensure there is enough to support the needs of the environment and the people of southern California. Water projects, such as Cadiz, may well provide a template for water management efforts elsewhere in the world, as climate change progresses.