Managers from the Goleta Water District and neighboring La Cumbre Mutual Water Co. held a groundwater management workshop Wednesday night, giving ratepayers a chance to see a new plan to optimize groundwater resources over the next several years.
Steve Bachman, a well-known water resources management expert, recently completed a study on the state of Goleta’s groundwater basin, and his prognosis was that it’s in good shape.
“It’s good to plan when you’re having good times, because it’s much more difficult to do that when you’re having bad times,” said Bachman, adding that during the late 1980s, water levels in Goleta’s groundwater basin dropped as low as 85 feet below sea level. Normally, he said, groundwater levels that low would have caused saltwater intrusion from the ocean. But because of its unique hydrogeology — which includes a rock-lined fault along the basin’s edge — saltwater intrusion did not occur when the aquifer was overdrawn.
Groundwater study is a nebulous and highly technical science, and it’s constantly evolving. Bachman’s study arose from decades of controversy over how best to measure groundwater levels, which wells should be used for the measurements and more.
Even now, there is some controversy over Goleta’s 1991 Safe Water Supplies Ordinance, which was established in response to a severe multiyear drought that saw the district’s groundwater levels lower than they had ever been on record. Essentially, the level needs to be kept at 100 percent of its 1972 level for the district to have what the ordinance considers an adequate drought buffer. Failing that, the district can’t sell new connections to the water distribution system, among other sanctions.
Jack Ruskey, a regular at Goleta Water District meetings, said the 1972 levels described in the report are based on assumptions and approximations.
“The last thing this community needs is for assumptions to be put in concrete and have both (Goleta’s and La Cumbre’s) boards base their planning on that,” he said.
Ruskey also took issue with the wells Bachman used for his study, saying there weren’t enough wells monitored.
“When you look at the map, there are vast areas of the basin not being monitored,” Ruskey said.
Bachman countered that he chose the seven wells used in the study because of past data available on them, and to avoid overrepresentation of data in certain areas.
“I would have used 13 wells if I thought it made a difference, but it wouldn’t have, so I didn’t,” he said.
The study also laid out provisions for more automated monitoring of the basin, both for water level and water quality. Contamination from gas stations and underground tanks over the years has caused a number of problem areas, but Bachman said that because of a clay layer on top of the aquifer, none of the 77 contamination sites listed by the California Water Resources Control Board have caused significant problems in Goleta’s groundwater basin.
Another issue touched on was use of recycled water. While some areas of Southern California are using recycled water to recharge groundwater basins, Bachman suggested that because of the negative association some people have with recycled water, it’s better not to have to use it in that capacity.
“I don’t think this basin needs recycled water for (groundwater basin) injection, he said, “but it’s always a good idea to use it for outside irrigation.”
Bachman suggested to the two boards that the groundwater plan be revisited every five years or so, even if only to make minor revisions.
— Noozhawk staff writer Ben Preston can be reached at bpreston@noozhawk.com.