California drought: City of Riverside sues over water restrictions

Days after unprecedented drought regulations took effect, the city of Riverside has filed suit against the State Water Resources Control Board, claiming the rules are “arbitrary and capricious.”

It’s the first lawsuit filed over the regulations, and the strongest objection so far on record to the state’s regulations, which aim to reduce urban water use collectively by a quarter and call on individual water suppliers to make deep cutbacks.

Under the rules, Riverside is required to reduce water use over the next nine months by 24 percent compared to a similar period in 2013 or face penalties of up to $10,000 a day. In a complaint filed in Fresno Superior Court, lawyers for the city counter that Riverside should have qualified for an alternative “reserve tier,” which only required cities to save 4 percent.

The water board defined the reserve tier as applying to cities reliant on local surface water supplies and that have at least four years of water set aside. At a meeting in April, the board said that including groundwater-supplied communities in the reserve tier would have been too complicated.

But Riverside counters that it is independent. The city argues that it has secured water for four years from its groundwater supplies in the Santa Ana River watershed. That water is in an adjudicated basin, meaning that multiple users, including Riverside, take water out and put water in. A watermaster monitors each user’s rights.

The State Water Resources Control Board has declined to comment on the lawsuit.

But Max Gomberg, the water board's senior environmental scientist for climate change, says having surface water to set aside isn’t the same as saving up groundwater.  “Groundwater for many areas is the savings account available during times of drought,” he says. “And the limited, 4 percent reduction tier is not available for communities who are relying on that savings account to weather the drought.”

Gomberg calls the emergency conservation regulation equitable, and characterizes the 4 percent reduction tier as limited. He points out that groundwater’s reliability is, at best, complex, because the amount of precipitation that will recharge an aquifer is unknown in the future, especially if drought continues. And about shared or adjudicated aquifers generally, he says, “often the number of pumpers drawing on the same source is unknown as is the amount of water that they are taking; making reliability in times of extended drought unknown.”

Separate from emergency drought-related regulations, the state is developing unprecedented rules for managing groundwater, in a process that will take years. 

This story has been updated.