Fish diversion effectiveness of a modular inclined screen system

A new type of fish diversion screen, known as the modular inclined screen (MIS), has beendesigned to provide effective fish protection at any type of water intake. Because the screenoperates at water velocities of up to about 3 m/s in the approach channel, the MIS is morecompact and cost-effective than existing low-velocity screens. The biological effectiveness of theMIS was evaluated in laboratory tests conducted with eleven fish species and in a field evaluationconducted with six fish species. During the laboratory tests, MIS passage survival exceeded 99%at velocities up to 1.8 m/s for most species, although lower survival was observed for therelatively fragile blueback herring at high operating velocities. The field evaluation demonstratedsimilar trends in passage success decreased considerably at velocities greater than 1.2 m/s,whereas passage of several riverine species typically exceeded 90% at velocities up to 1.8 m/s.The laboratory and field evaluations have demonstrated that the MIS has potential to successfullydivert a wide range of species at water intakes