Groundwater adjudication: burden of proof.

Assembly Member Hart's groundwater adjudication legislation modifies how courts evaluate challenges to groundwater sustainability agency (GSA) decisions by establishing new evidentiary standards and technical reporting requirements. The bill requires parties contesting GSA actions under approved sustainability plans to meet a substantial evidence burden of proof during judicial review.

In basins with approved groundwater sustainability plans, courts must now request technical reports from GSAs documenting groundwater usage by non-participating parties. These reports serve as prima facie evidence of physical facts, though parties retain the right to present rebuttal evidence. While GSAs cannot charge fees for producing these reports, courts will allocate reimbursement for actual expenses, including staff time and associated costs, among parties in an equitable manner.

The legislation also expands provisions for special masters in groundwater adjudications. Courts may appoint special masters to investigate technical and legal issues, facilitate joint fact-finding between parties, and develop preliminary injunction proposals. The State Water Resources Control Board and Department of Water Resources may recommend candidates or review qualifications for special master appointments. Courts determine special master compensation and can adjust terms after providing notice and opportunity for parties to respond.