Reclamation and reuse of irrigation sediments

Excerpt

IRRIGATION canals and drainage ditches often require periodic cleaning to remove wind-blown or water-deposited sediments. Ponds used to trap sediment from irrigation runoff and food processing wastewater also require periodic cleaning if they are to remain effective. The freshly removed sediment is usually piled next to the canals or ponds for drying and temporary storage.

Dredge materials often are stored near the source until the piles become so large they constitute a nuisance. Removal then is necessary. Sediment piles frequently remain in place for 10 years or more.

A case history

Two large irrigation tracts in southern Idaho are served by the North Side Canal Company, which annually removes about 325,000 tons of sediment from its canals and drains, and the Twin Falls Canal Company, which each year removes about 86,000 tons of sediment from its canals and drains (2). These quantities exclude the sediment removed by farmers from sediment ponds within the irrigation tracts. The two irrigation companies supply irrigation water to 363,000 acres.

The logical place to put the sediment is back onto the eroded fields or on areas that need fill. The materials usually are quite fertile with respect to phosphate and …