NMFS-CV-BO-IWW-08

Fish and Aquatic Species Exclusion While Installing Diversion Structures

Fish shall be excluded from occupying the work area by blocking the stream channel above and below the work area with fine-meshed block nets or screens. Mesh will be no greater than 1/8-inch diameter. The bottom of a seine must be completely secured to the channel bed. Screens must be checked twice daily and cleaned of debris to permit free flow of water. Block nets shall be placed and maintained throughout the dewatering period at the upper and lower extent of the areas where fish will be removed. Block net mesh shall be sized to ensure salmonids upstream or downstream do not enter the areas proposed for dewatering. Net placement is temporary and will be removed once dewatering has been accomplished or construction work is complete for the day.