What probationary groundwater status means in California
Probationary groundwater status is California stepping in after a local water district plan fails, taking over enforcement and charging a new fee to anyone who pumps there. The status exists because of the Sustainable Groundwater Management Act, a law passed in 2014, which required 94 of the 515 groundwater basins in California to file a plan proving they could stop pumping the aquifer underneath them faster than it refills. Those 94 basins sit under 98% of all the groundwater pumped in the state. More than 260 local groundwater sustainability agencies formed across more than 140 of those basins to write the plans, and the last statutory filing deadline passed on January 31, 2022.
These 3 shares each measure a different statewide total, pumping, people and farmland, over the same 94 basins, not 3 slices of 1 whole.
Show the numbers
| Groundwater pumping | 98 |
| State population | 83 |
| Irrigated farmland | 88 |
As of an April 2026 update from the Department of Water Resources, the agency that reviews every plan, 81 basins statewide now operate under an approved plan, covering 71% of statewide groundwater use in water year 2024. Four high priority basins, Chowchilla, Delta Mendota, Kaweah and Kern County, had a plan found inadequate, corrected it, and returned to the department for ordinary review. Three more basins stayed inadequate long enough to be referred to a second agency, the State Water Resources Control Board, which can order fees and mandatory reporting where the department cannot. Adding 81, 3 and 4 gives 88 basins with a status reported by the department, a MAOWCE calculation, 6 short of the 94 basins the law required to file a plan, a gap neither agency explains in the pages read for this article.
What happens once a basin is designated probationary
Two of the 3 referred basins, Tulare Lake and Tule, are now designated probationary, meaning the state board runs enforcement directly. The department found the Tulare Lake Subbasin 2020 plan incomplete in January 2022, found the revised plan inadequate in March 2023, and the state board designated the subbasin probationary on April 16, 2024. Measuring every extraction became mandatory on July 15, 2024, the first reporting period ended September 30, 2025, and the first extraction reports are due May 1, 2026. A third basin, Pleasant Valley, is being evaluated for the same designation.
The 81 approved count is statewide and is not limited to only the 94 required basins, since a small number of lower priority basins also file plans voluntarily. These 4 bars do not sum to 94.
Show the numbers
| Basins required | 94 |
| Plan approved | 81 |
| Returned to department | 4 |
| Sent to state board | 3 |
The fee a pumper in a probationary basin now owes
A well owner in a probationary basin like Tulare Lake now owes an annual base filing fee of 300 dollars per well, plus a volumetric fee of 20 dollars for every acre foot extracted, a measure equal to the water needed to cover 1 acre of land 1 foot deep. Filing late adds a penalty of 25% per month, capped at 3 times the annual fee. A small domestic well pumping 2 acre feet a year or less is exempt from reporting. On April 7, 2026, the board excluded small extractors within 2 miles of the Friant Kern Canal from the fee. An ongoing lawsuit has separately blocked enforcement inside 2 named local agencies, Tri County Water Authority and Southwest Kings, while the rest of the subbasin stays covered, as of August 2026.
Basins, not agencies, are what the state actually tracks
The law created more than 260 local groundwater sustainability agencies, but the state does not publish a compliance figure for each one individually. A plan is filed once per basin, not once per agency, so most basins are managed by several agencies filing 1 shared plan together. Every figure above, approved, inadequate, or probationary, is a basin count, not an agency count, because a basin is the level at which California itself keeps score.