KAWEAH RIVER BASIN CLOUD SEEDING PROGRAM

The Kaweah River cloud seeding program has operated since the completion of Terminus Dam in 1962.  RHS Consulting began operating this seeding program in 2010. The goal of the Kaweah River cloud seeding program is to augment precipitation falling in the Upper Kaweah River Basin above Lake Kaweah to increase water supplies for irrigation and hydroelectric generation. The program is sponsored by the Kaweah Delta Water Conservation District. Seeding materials are released upwind of the Kaweah program target area using aircraft. The program is designed to seed winter storms during November through April each winter season.

The Kaweah River is a 58.5-mile (94.1 km) long river located in the Southern Sierra Nevada in California. Its headwaters originate in Sequoia National Park from four major forks flowing southwest through Lake Kaweah reservoir and onto an alluvial plain northeast of Visalia, Ca. 

The Kaweah watershed covers approximately 500 square miles, characterized by rugged mountainous terrain with granite spires reaching above 12,000 feet elevation along the Great Western Divide of the Sierra Nevada. The high elevation basins are dotted with small lakes and tributary streams. These streams fall rapidly from the high mountain area, finally emerging from the upper watershed entering Lake Kaweah. Lake Kaweah provides water for hydroelectric power production and serves as a flood control and water management facility for the rich agricultural community in the southern San Joaquin Valley.

program location and goals

• The Kaweah River target area is outlined above in red. Surrounding the target area are the Kern River, Tule River, and Cottonwood Creek Watersheds shown in white.
  
• Identifying seedable opportunities and modifying candidate clouds that pass over the Kaweah River watershed to enhance precipitation for increasing snow pack and streamflow into Lake Kaweah and the Terminus Dam hydrogenation system are the main goals of the program.
• Statistically based assessments of seeding effects are made using April snow survey data and streamflow data. The Tule River and  Cottonwood Creek. Cumulative regression ratios analyses indicate the program produces an average of 8-10% increase in streamflow entering Lake Kaweah annually. Precipitation increases based on SWE analyses have shown that the seeding effects are confined to the upper elevations of the basin.