The South San Joaquin Irrigation District is continuing the process needed to address Woodward Reservoir spillway deficiency issues identified by the California Division of Safety of Dams.

The state determined several years ago the Woodward Reservoir Dam lacks a properly designed spillway, which is considered a dam safety deficiency.

Now the state has approved the direction SSJD is moving in to put a properly designed spillway in place, the district board when they meet Tuesday at 9 a.m. is being asked to authorize the next phase of design and engineering.

The implementation plan, prepared by Provost & Pritchard, presented to the state in September 2025 outlined the district’s conceptual spillway approach located near the existing boat ramp and Fisher Point Day Use Area.

It included updated hydrologic analysis, proposed design criteria, project schedule, and a cost estimate.

In December, the state indicated the conceptual spillway approach is acceptable and that the proposed project schedule is reasonable.

The state, at the same time, requested that the district evaluate potential downstream mitigation measures associated with spillway discharges.

The reservoir 16 miles northeast of Manteca is off of 26-Mile Road and is near Littlejohns Creek and Rock Creek.

The 36,000 acre reservoir serves as the SSJID’s in-district storage and is fed by water diverted in the main canal at Goodwin Dam on the Stanislaus River.

The reservoir stores irrigation water for 56,000 acres of farmland and supplies domestic water for over 220,000 residents in Manteca, Lathrop, and Tracy.

The reservoir was built in 1916 to minimize crop damage from water shortages following a dry winter in 1915. It was built for $600,000.

To contact Dennis Wyatt, email dwyatt@mantecabulletin.com