Canals can lose 30 to 50 percent of their irrigation water through seepage. Canal-lining technologies can minimize seepage losses at reasonable costs. The Canal Lining Program is a specialized demonstration program designed to investigate alternative canal-lining materials. Traditional canal-lining materials typically include compacted earth, reinforced or unreinforced conerete, and (more recently) buried geomembranes. However, for some jobs, these materials are not always viable because they:

1. are not locally available (such as compacted earth)
2. are too expensive (such as reinforced concrete)
3. require easy access for heavy construction equipment (such as slip-forming unreinforced concrete)
4. require extensive overexcavation and subgrade preparation (such as buried geomembranes)

This study looks at alternative canal-lining materials that are less expensive, easier to construct with limited access, and compatible with severe rocky subgrades such as the fractured volcanic basalt common in the Pacific Northwest.

To date, over 30 test sections have been constructed in several irrigation districts throughout the Pacific Northwest. The lining materials include combinations of geosynthetics, shotcrete, grout-filled mattrasses, soil, elastomeric coatings, and sprayed-in-place foam. Some test sections are almost ten years old.

The Canal Lining Program publishes several reports and updates on the implementation of various canal-lining materials:

• Bitter Root Irrigation District Main Canal, Oct. 2001
• Construction Cost Tables for the Canal Lining Projects (June 2001; 4pages; 102 KB)
• Canal-Lining Demonstration Project 2000 Supplemental (January 2000; 46 pages; 3.5 MB)
• Canal-Lining Demonstration Project Year 7 Durability Report (September 1999; 156 pages; 13.2 MB) - The Deschutes Canal Lining Demonstration Project works to develop low-cost canal-lining technologies to reduce seepage over severe rocky subgrade conditions.
• Canal-Lining Demonstration Project Year 10 Final Report (November 2002; 26 MB PDF)