Local GSAs hire contractor to develop groundwater sustainability plan


The Colusa Groundwater Authority, in a joint meeting Oct. 30 with the Glenn Groundwater Authority, selected Davids Engineering to help the two agencies work together to develop a single Groundwater Suitability Plan for the Colusa Subbasin. 

The Chico-based firm has been contracted to complete the Hydrogeological Conceptual Model and water budgets for the Colusa Subbasin, set groundwater management standards and objectives, and identify actions or projects that meet the standards and objectives outlined by the Sustainable Groundwater Management Act of 2014. 

The GSAs’ goal is to establish a monitoring program and plan that is geared at sustaining groundwater by 2042, officials said. 

The Board of Directors reviewed four proposals last week, ranging between $551,300 and $911,000, before selecting Davids Engineering, which came with the highest price tag. 

“It was a difficult choice,” said Darrin Williams, a private pumper on both the Colusa Groundwater Authority Board of Directors and Technical Advisory Committee. “In the end, we felt very comfortable with Davids.”

Williams said the TAC recommended Davids because the firm demonstrated extensive knowledge and understanding of local groundwater conditions, and they felt Davids would offer a seamless transition from current to future projects in the Colusa Subbasin. 

Property owners in Colusa County voted in a $1.31 per acre tax to establish and fund the new regulatory agency. Glenn County property owners approved a $1.75 per acre tax through a similar “protest hearing” process. 

Directors on the two groundwater authorities also agreed last week that the Colusa Groundwater Authority would apply for a $1 million grant made available by Proposition 68, a general obligation bond which voters passed in 2018 to fund projects related to water infrastructure projects and environmental protection. 

Eligible projects include the development of the local Groundwater Sustainability Plan for the Colusa Subbasin, said Mary Fahey, CGA executive director.

Davids Engineering will write the grant proposal, which must be submitted to the California Department of Water Resources by Nov. 15. 

CGA and GGA officials anticipate that sustaining groundwater will eventually require them to regulate when and how much groundwater can be pumped, require them to measure groundwater and report those figures to the state, charge fees for groundwater use, and any other enforcements demanded by the Groundwater Sustainability Plan, once it is written. 

Officials said they would like to start with a pilot program for voluntary well metering and groundwater use reporting by local property owners. 

The Groundwater Sustainability Plan (and the funding mechanism) will be reviewed every five years, Fahey said.