Less than Zero: Despite decades of accepted science, CA and AZ are still miscounting water supplies

[marmar]

(ProPublica) DEEP BENEATH the bleached-out, dusty surface of the drought-stricken West is a stash of water sequestered between layers of rock and sometimes built up over centuries.

Officials in the Colorado River basin states have long treated this liquid treasure as a type of environmental retirement account — an additional supply of water they can raid to get through the driest years and make up for the chronic overuse of the rivers themselves.

In recent years, the withdrawals have taken on even more importance: At least 60 percent of California’s water now comes from underground, some researchers say. Arizona, staring down imminent rationing of Colorado River water, pumps nearly half its supply from aquifers.

But in allowing their residents to tap underground resources this way, regulators and legislators in Southwestern states have ignored an inconvenient truth about how much water is actually available for people to use: In many places, groundwater and surface water are not independent supplies at all. Rather, they are interconnected parts of the same system.

The science has been clear for the better part of a century. Drawing groundwater from near a stream can suck that stream dry. In turn, using all the water in streams and rivers lessens their ability to replenish the aquifers beneath them. Farmers who drill new wells to supplement their supplies with groundwater are often stealing water from their neighbors who hold rights to the rivers above them. This understanding has been the foundation of the U.S. Department of the Interior’s water accounting for decades, and was used by the U.S. Supreme Court to decide one of the most significant water contests in history. ................(more)

https://projects.propublica.org/killing-the-colorado/story/groundwater-drought-california-arizona-miscounting-water

[DetlefK]

1. "1931, when Arizona’s Supreme Court ruled that ground and surface waters were separate."

"Changing it might bring economic turmoil because Arizona’s economy has grown up based on that system. As a result, he said, “We do not attempt to determine how much of the pumping might be depleting the stream flow.”"


Because knowing stuff would mean changes in policies. And we cannot allow to know too much about water-supplies, guns or marijuana.

[xocet]

3. At least, the federal government, apparently, is using the knowledge of the connection....

Less Than Zero
Despite decades of accepted science, California and Arizona are still miscounting their water supplies

by Abrahm Lustgarten, ProPublica
June 16, 2015

...

"What California and Arizona are both so reluctant to accomplish, the federal government has been routinely doing for more than 50 years: counting the waters it controls as from a single source, and using an honest estimate of the total to determine the resources available for people to use.

But that kind of accounting is far from easy, and it requires vigilance."

...

https://projects.propublica.org/killing-the-colorado/story/groundwater-drought-california-arizona-miscounting-water

[JonLP24]

2. I believe the Southwest is one of the highest areas

for arsenic concentration. I think those are lower populated counties such as Miami while I understand Maricopa gets most of their water from Lake Mead. Overall about half or a little less than half comes from groundwater. As I understand it though not following water politics in Central Arizona Project and Salt River Project are tasked with managing the water resources they do have in a way that is said to be "efficiently" but not up to speed on the water politics of all this or what California is doing.

[xocet]

4. K & R n/t