In the project area, the main canal separates into two supply lines which serve 27,186 acres by gravity flow. About 20 miles below Black Canyon Dam, a pumping plant lifts water from the main canal into a lateral system serving 26,014 acres. The 6,881-acre Notus Unit of the Payette Division obtains water from two Arrowrock Division drains south of the Boise River near Caldwell. The three acreages are in the Black Canyon Irrigation District. Both canals divert water from the Payette River at Black Canyon Dam.
Power is produced at Black Canyon Dam.
It is a rolled earth and rockfill embankment structure containing approximately 9,653,000 cubic yards of material. The base width of the dam is 3000 feet, the crest length is 1350 feet long and the crest width is 40 feet. The 40-foot crest width contains a graveled roadway surface for Forest Service Road No. 134. The embankment consists of rolled clay, sand, and gravel, protected by the riprap and rockfill covering. This center section is supported by stable, semi-impervious sections graduated in coarseness toward the outside slopes.