Background

The Putah South Canal in Vacaville, CA, which supplies irrigation water for the Solano Irrigation District, was having a continuing problem with seepage. After only partially mitigating the problem by lowering the surface height of the canal water, the decision was made to reline the worst section of the canal, which was about 4,000 feet in length.

Solution

A polyethylene geomembrane with a textured surface manufactured by GSE was chosen and installed by our network. The installation began at the lowest point of the canal and proceeded upgrade. The geomembrane panels were installed transverse to the canal and the panels were fusion welded together. They were then mechanically attached to the existing concrete liner at the top of the canal slopes using hit anchors.

Shotcrete with reinforcing fibers was spray-applied to a 2-inch (5 cm) thickness. The textured membrane allowed for applying the complete shotcrete thickness at one time instead of in three applications as would have been necessary using a smooth-surfaced geomembrane. Expansion and contraction joints were added at 12-feet (3.5 cm) centers.

The Result

One section was completed in 1989. A second section, using the same method, was completed in 1993. The lining immediately eliminated the water loss and has continued to prevent seepage since.

Further Reading

• HDPE Textured Geomembrames

Previous Case Study    |     Next Case Study