The present invention provides a method of killing larvae of sessile invertebrates in the settlement stage in water, comprising the step of irradiating light comprising the spectrum of 409 to 412 nm, to the larvae in the settlement stage.

An apparatus for holding back, and diverting, fish in bodies of water by the arrangement of parallel cables (S) braced between two or more abutments (W), wherein the distance between the cables is small enough to prevent fish from swimming through the apparatus.

The present invention provides a method of stopping larvae of sessile invertebrates in the settlement stage from swimming or crawling in water, by irradiating light comprising the spectrum of 409 to 412 nm and a part of 400 to 440 nm, to the larvae in the settlement stage.

A mobile electric field monitor with a floatable housing, an electric field probe, and a computer processor to measure the electric field generated by an electrofisher while the electrofisher is being used in a body of water, this mobile electric field monitor is coupled to computing system to generate a three dimensional map of electric field.

An aquatic electrical barrier that has the electrodes configured in a matrix array configuration, where each electrode element of the matrix array is mounted either directly on the bottom of a water channel or on extendable rods; the matrix array is controlled so that aquatic species may be physically moved by the aquatic species physiological response to a time-varying and spatially-varying electrical field.

A netting conduit. The conduit defines a continuous channel extending between a first open end and a second open end. The conduit is fabricated from netting having a mesh size sufficient to prevent most fish from traversing through the netting material. The conduit tapers from the first open end to a midsection and enlarges from the midsection to the second open end. The longitudinal edges of the conduit can define a parabolic shape. The conduit further includes stakes that are usable to anchor the conduit to the bed of the waterway in which the conduit is in use.

The fish screen for a suction strainer includes at least one first plate having a central opening formed therethrough, a second plate, a helical spring, and a mesh bag. The helical spring has opposed first and second ends, with the first end secured to the at least one first plate and the second end secured to the second plate. The helical spring has first and second portions positioned respectively adjacent to the first and second ends. The second portion has a smaller diameter than a diameter of the first portion. The mesh bag releasably and removably covers and receives the at least one first plate, the second plate and the helical spring. The second portion of the helical spring is adapted for releasably holding a free end of a suction strainer received within an interior of the helical spring through the central opening of the at least one first plate.

A collection device for aquatic life and debris for a traveling water screen. The collection device allows sharing of water provided from a high pressure nozzle while shielding aquatic life from a high pressure spray produced by the high pressure nozzle. The collection device enables separate collection of items exposed to a high pressure spray and items protected from a high pressure spray while reducing water costs. The collection device includes a first compartment for collecting aquatic life collected by a water screen and a second compartment for collecting debris collected by the water screen. A shield dissipates or blocks a high pressure spray directed into the second compartment from entering the first compartment. A filter allows fluid to flow from the second compartment into the first compartment while blocking aquatic life in the first compartment from entering the second compartment.

The fish screen for a suction strainer includes at least one first plate having a central opening formed therethrough, a second plate, a helical spring, and a mesh bag. The helical spring has opposed first and second ends, with the first end secured to the at least one first plate and the second end secured to the second plate. The helical spring has first and second portions positioned respectively adjacent to the first and second ends. The second portion has a smaller diameter than a diameter of the first portion. The mesh bag releasably and removably covers and receives the at least one first plate, the second plate and the helical spring. The second portion of the helical spring is adapted for releasably holding a free end of a suction strainer received within an interior of the helical spring through the central opening of the at least one first plate.

A flood protection system (10) on a watercourse (16) with a flood-prone area (18) includes a main pipe (12) along the watercourse (16) in this flood-prone area (18). At least parts of the watercourse (16) are guided through the main pipe (12) in the direction of flow (28). A drive turbine (62) in the main pipe (12) increases the flow velocity of the flowing water (16) in the main pipe (12) in the event of flooding, the main pipe (12) flowing back into the flowing water (16).