With hard hats, shovels, and looking toward the future, South San Joaquin Irrigation District (SSJID) and Oakdale Irrigation District (OID) officially kicked off the Canyon Tunnel Project on Monday, Aug. 4, 2025. The 12,000-foot water tunnel is designed to revolutionize how water moves through the Sierra foothills. Built beneath steep canyon walls and through an ancient, buried riverbed, the tunnel will bypass a fragile section of the Joint Supply Canal (JSC), protecting critical water deliveries to cities, farms, and families across SSJID and OID’s districts for generations to come.
“This tunnel is a lifeline for our communities,” said Glenn Spyksma, SSJID Board President. “We’re building a future where water keeps flowing no matter what nature throws our way.”
Dozens gathered along Tulloch Dam Road at Goodwin Dam to witness the launch of this major infrastructure upgrade. The Canyon Tunnel is designed to eliminate risks from landslides that have threatened the century-old canal, including a 2013 rockfall that nearly crippled early-season water deliveries. The new tunnel will ensure a safe, uninterrupted water supply to SSJID’s constituents representing 50,000 acres of farmland and the cities of Escalon, Manteca, Lathrop, and Tracy. Likewise, the tunnel will also protect OID’s ability to serve approximately 26,000 acres of irrigated farmland and raw water for domestic purposes to the community of Knights Ferry.
“OID and SSJID have always worked together to solve big challenges,” said Tom Orvis, OID Board President. “This project will take us into the next 100 years with confidence, safety, and strength.”
The project is jointly funded by SSJID and OID, with cost shares based on historic water use from the Joint Supply Canal, a shared facility delivering water from the diversion at Goodwin Dam to OID and SSJID facilities and customers. SSJID is contributing 72 percent of the total project cost, while OID is funding the remaining 28 percent. This collaborative investment reflects the shared commitment of both districts to securing a safe, reliable water future for their communities.
Construction is now underway and expected to wrap up in 2028. Operating with minimal maintenance, the tunnel offers modern reliability from a century-old canal system originally built in the early 1900s. It will also reduce costly maintenance and minimize potential risks during the irrigation season.
For more details, visit canyontunnelproject.org.
South San Joaquin Irrigation District was established in 1909 and is headquartered in Manteca. SSJID provides agricultural irrigation water to about 50,000 acres surrounding Escalon, Ripon and Manteca, and wholesale drinking water to over 200,000 residents in Manteca, Lathrop, Tracy, and in the future, Escalon.
Oakdale Irrigation District was established in 1909 and is headquartered in Oakdale. OID delivers agricultural irrigation water to over 2,900 connections across approximately 81,000 acres in Stanislaus and San Joaquin counties and provides domestic water service to more than 700 customers.
SSJID in partnership with OID, own and operate the Tri-Dam Project, a series of storage reservoirs and electric generation facilities that produce zero-carbon hydropower in the Stanislaus River watershed.
