California is one of only two states in the nation that have not comprehensively regulated their groundwater. The other is Texas.
The California Constitution states and courts have upheld the doctrine that landowners whose property overlies an underground aquifer have the right to pump reasonable amounts of water from that aquifer as long as it is put to a beneficial use, such as irrigating crops or supplying drinking water.
“Therefore, all local governments are highly constrained in how they can regulate groundwater,” said James Caruso, a senior long-range planner with the county.
Like many local governments, San Luis Obispo County is trying to manage its groundwater cooperatively. The idea is that individual water users, acting with enlightened self-interest, can voluntarily agree to limit water use before disaster strikes.
However, experience and human nature argue against this approach being successful.
“It is frequently argued that resources shared in common with few restrictions are ultimately overused, as all participants are encouraged to maximize their use and no participant has an incentive to consider long-term consequences of overuse,” the Sacramento-based Water Education Foundation said in its 2011 publication Layperson’s Guide to Groundwater.
Groundwater basins in overdraft frequently result in lawsuits, and courts are forced to step in and adjudicate water rights. In these cases, a water master is appointed who has the authority to determine the basin’s safe yield by controlling pumping via pump taxes and other means designed to discourage excessive use.
However, litigation is expensive and time-consuming because the courts must make many factual determinations such as the identity of pumpers, each pumper’s historical use and the boundaries of the groundwater basin.
Twenty-two groundwater basins in the state have been adjudicated, including the Santa Maria basin in 2008. Another option is to have the state Legislature create a special groundwater management district.
Similar to the courts, such a district can limit the amount each property owner can pump out of the basin or establish pumping taxes. There are 13 of these special districts in the state. One of them is the Monterey Peninsula Water Management District.
“The real story here is how difficult it is for a local government such as our county to do something about a declining groundwater basin when the users are so diverse, the Constitution limits the county’s authority, other local governments have an important role to play in the resource discussion, and the entire subject is so bound up in economics,” Caruso said. “Remember, groundwater is a common good, and people react to it as such.”