Performance Testing of Submerged Intake Screen

A test of the long-term operating performance of a wedgewire-screen intake system in the Mississippi River is described. The screen was a 13.5-ft (4.1-m) long, 3-ft (0.91-m) diameter cylinder with 1 mm slot openings, providing 40% open area. It was placed 3-ft (0.91-m) above the river bed 9-ft below normal pool elevation at a distance of 150-ft (46-m) from the bank of the river. Water was drawn in through the screen by an inclined one-stage axial-flow pump on the bank of the river. The pump was rated at 10 cfs (0.28 m³s) at 20-ft (6.1-m) head and was driven by a 50-hp motor. The test facility was in operation on a round-the-clock basis for approximately 9 months, with shutdowns once a day for air or water back-flushing. The results showed that the system could be operated and maintained with an effort that would be acceptable in an actual power-plant cooling water make up system.