South San Joaquin Irrigation District is assessing storm damage to its water delivery system from rockslides in the High Sierra to key canals above Knights Ferry and on the valley floor.

SSJID Public and Government Relations Manager Katie Patterson said this past week that engineers and crews are determining strategies to repair the issues.

They run the gamut from unstable canyon walls above supply canals, destroyed sections of canal lining spots in the joint supply and main canals, as well as rock slides.

It is too early to determine if the repairs will require a delay of the start of SSJID irrigation season that is typically in mid-March.

Patterson said the district is committed to “doing repairs right.”

Some of the damage is to the Tri-Dam Project that SSJID operates jointly with Oakdale Irrigation District to capture 600,000-acre feet of water rights the two districts share on the Stanislaus River watershed.

The joint supply canal operated by the two districts is one of the trouble spots. It is in the narrow and steep canyon on the Stanislaus River above Knights Ferry.

SSJID regulates water from Woodward Reservoir to irrigation customers via an extensive system, which includes 18 miles of main distribution canal, 312 miles of lateral pipelines, and 38 miles of open-channel canals. Nearly all of SSJID’s distribution system relies on gravity to convey water, an engineering feat that provides significant cost savings to local customers.

Patterson said the district will determine if its crews can do the needed repairs or if outside contractors will be needed.

She said SSJID crews worked around the clock during the storms to make sure canals were kept clear and that water didn’t create issues with key roads such as Highway 120 near Harrold Road east of Escalon.

The district worked closely with the City of Manteca to regulate stormwater runoff from the city that uses SSJID canals to reach the San Joaquin River.

The storms hit at high tide in the Delta so the ability to release water from the French Camp Outlet that runs along Manteca’s western city limits was somewhat constricted.

“The city worked with us to hold back water when it was needed,’ Patterson said.