California Supreme Court probes ‘reasonable’ water use in Kern River

The California Supreme Court heard arguments over whether a 2023 lower court order protecting Kern River flows for fish improperly ignored a constitutional 'reasonableness' requirement on water use, a question that stems from Bakersfield's effort to reduce river flows. An appeals court sided with the city in April 2025, prompting conservation group Bring Back the Kern to appeal further.

Attorneys disagreed over whether judges must weigh reasonableness even when no party raises it, with the city's attorney arguing the state Constitution demands it and Bring Back the Kern's attorney countering that Fish and Game Code Section 5937 already requires enough water to keep fish in good condition, full stop.

The state attorney general's office urged deference to the Legislature's existing definition of reasonable use rather than letting justices substitute their own judgment, while a water agency attorney proposed a sliding scale and asked the case be sent back to the trial court to weigh reasonableness directly.

The full dispatch is available from the source below.