7K in acre feet needed in 2030

In 2030, the city will need to acquire about 7,000 acre feet of surface water a year to recharge groundwater, according to recently released data.

The numbers are based on the city’s population estimates, and its growth boundaries, for the next 20 years. The information is derived from a study done by Fresno based hydrologist Kenneth Schmidt, who was hired as a consultant in June.

In California, and the Central Valley, a significant portion of the population relies on groundwater as a source for drinking water. A lack of state regulation has led to overdrafts, forcing people to dig deep wells to find water, which is sometimes beyond their reach.  

The report shows that the city is currently over-drafting its groundwater supply by about 1,200 acre-feet per year.

“It’s not such a large amount that it's insurmountable,” Sean Geivet, manager of the Porterville Irrigation District, said. “We’re probably as well off in the Porterville area as any of our sister cities in the area.”

With statistics in hand, the city’s public works staff will find a plan to obtain surface water on a yearly and long term basis to recharge the ground water.

“We’re getting ourselves in line so we can purchase this water when it becomes available,” Public Works Director Baldo Rodriguez.

According to measurements taken in November, residents who use wells in the Porterville Irrigation District are relying on a water level of 127 feet — a drop in 19 feet since February.

Geivet has been involved in water district management for approximately 11 years now. He agrees with other water experts who say that recharging water is critically important to sustaining a community.

In the Porterville area, “there’s not an endless supply of groundwater,” he said. “It’s not deep like out in the west side.”

In the last year, the city purchased 1,271 acre feet of water from other local irrigation districts in order to recharge its groundwater. It cost about $40,000, according to City Manager John Lollis.

A similar operation has been going on for the past several years.

Groundwater can be recharged by injecting water underground via wells or by putting surface water into storage basins.

According to Schmidt’s analysis, the major groundwater recharging corridors are the Tule River and the Porter Slough.

Geivet considers the city’s latest efforts to be positive steps.

“They are on the right track to being able to mitigate that water draft into the future,” he said.

Contact Jenna Chandler at 784-5000, Ext. 1050, or jchandler@portervillerecorder.com.