Groundwater at stake

AquAlliance and local groundwater users defend supplies

Mr. Brobeck is a water policy analyst for AquAlliance (, an organization that exists to defend Northern California waters and encourages public involvement in its well monitoring program.

Selling more water out of Northern California is not popular in our region. Glenn Colusa Irrigation District (GCID) recently held a public workshop in Hamilton City offering to do just that. The meeting was originally scheduled in Chico but moved out of town when the host, California Water Service Co., realized the concept was extremely controversial and likely to draw a crowd of concerned citizens. Groundwater-dependent farmers/homeowners and public-interest organizations found their way to the remote conference room to defend regional groundwater.

GCID used a taxpayer-funded grant to install colossal deep wells adjacent to its canal system that can be cranked up to pump from the Tuscan Aquifer system, the source of drinking water for Chico. State and federal agencies have spent millions to investigate the concept of using the Tuscan Aquifer as a source of “new water” to meet demands from south of Sacramento.

A GCID document explains the basic idea is to use our region’s groundwater to sell water to other districts and refill pumped-out aquifers in the San Joaquin Valley. The district casually warn us that this will have negative impacts on Butte Basin groundwater uses.

GCID knows its plan would deplete local streams and reduce groundwater in existing wells. Its engineers presented statistics to assure us those impacts would be “relatively small,” explaining that the project would increase pumping only 2-3 percent from the entire Sacramento Valley.

But they did not analyze the proportional increase in the Butte Basin Aquifer (Vina to Sutter Buttes). They presented “average” aquifer declines of only 2-6 feet but failed to map out water-level slumps of 40-80 feet that would occur in areas directly influenced by the district pumps. These omissions and inappropriate scales of analysis are bold attempts to misinform the public.

AquAlliance testified that GCID stands to profit by selling water to distant water districts, but relentless demand from south-of-Delta water purveyors will never be satisfied. Sustaining the agriculture, communities and environment of the Butte Basin requires a balanced aquifer system and unity of the regional population. The GCID proposal will result in historically low Oroville reservoir levels, destabilized aquifers, and divided local populations.

Sacramento Valley irrigation districts must cease conspiring with Southern California water marketers and resume their alliance with other Butte Basin stakeholders.