Local nonprofit water advocates AquAlliance filed a lawsuit on Friday (April 15) against the U.S. Army Corps of Engineers over Gov. Jerry Brown’s proposed multibillion-dollar water-tunnel system under the Sacramento-San Joaquin Delta, now branded California WaterFix.

The lawsuit alleges that the Army Corps violated the Freedom of Information Act (FOIA) by withholding records requested by AquAlliance—first by failing to “conduct a reasonable search for records,” the document reads.