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.

Zero-ascend omnispecies (ZAO) attraction system includes a fish passage attraction module that can be deployed in a fishway where water flows downstream. The fish passage attraction module includes a body having a first end and an opposite second end, first adaptor adjacent the first end and second adaptor adjacent the second end. The adaptors are configured to alter water flow fields downstream of the module so as to attract fish to an entrance thereof.

A spur dike type fishway inlet includes an upstream flow block wall, an extra water supply nozzle, and an artificial fish reef. The upstream flow block wall is arranged upstream of a fishway inlet; the starting end of the upstream flow block wall is connected with the upstream side wall of the fishway inlet through a connecting shaft and a hydraulic strut. The extra water supply nozzle is installed in the fishway inlet and is connected to the upstream of a power station through a pipeline to directly supply water to a high water head. The artificial reef is set up within the shielding range of the upstream flow block wall.

A water intake and pretreatment system (10) comprising an inlet for delivering water from a natural source to a reservoir (12); said inlet to reservoir having a net screen (16) to prevent entry of organisms above a predetermined size and including a one-way gate (30) to allow organisms to exit the reservoir; said reservoir further comprising a granular filter media for water and algae filtration; and a drainage layer for removal of filtered water from the granular filter media to a drainage outlet. A local backwashing apparatus (40) is included for localized backwashing of the granular filter media.

A spur dike type fishway inlet includes an upstream flow block wall, an extra water supply nozzle, and an artificial fish reef. The upstream flow block wall is arranged upstream of a fishway inlet; the starting end of the upstream flow block wall is connected with the upstream side wall of the fishway inlet through a connecting shaft and a hydraulic strut. The extra water supply nozzle is installed in the fishway inlet and is connected to the upstream of a power station through a pipeline to directly supply water to a high water head. The artificial reef is set up within the shielding range of the upstream flow block wall. A device for luring the fish by adopting fish target keeping behavior is provided.

A water intake and pretreatment system (10) comprising an inlet for delivering water from a natural source to a reservoir (12); said inlet to reservoir having a net screen (16) to prevent entry of organisms above a predetermined size and including a one-way gate (30) to allow organisms to exit the reservoir; said reservoir further comprising a granular filter media for water and algae filtration; and a drainage layer for removal of filtered water from the granular filter media to a drainage outlet. A local backwashing apparatus 40) is included for localized backwashing of the granular filter media.

A sea water intake system comprising a main sea water intake pipe, one end of the sea water intake pipe being provided with a centrifugal chamber, the chamber having at least one tangential inlet for entry of sea water to cause rotation of the sea water in the chamber. The other end of the intake pipe terminates in a sump, the sump having a water level lower than that of sea level and having a pump to transport sea water from the sump through a delivery pipe to a treatment plant. A central region of the centrifugal chamber is in fluid communication with a substantially vertical airlift pipe having an air inlet at, or close, to the chamber and a water exit remote from the chamber.

Aspects of the present disclosure involve hydraulic systems and methods for altering a flow of a body of water, such as a river, channel, and/or other flowing or uncontained bodies of water. In one aspect, a hydraulic system provides a velocity barrier for the impedance of aquatic organism migration. More particularly, the velocity barrier may be adapted based on the swimming capabilities of one or more aquatic organisms to impede migration. The aquatic organism may be one or more species of fish, such as species sea lamprey (Petromyzon marinus). The example implementations shown and described herein reference the restriction of the sea lamprey. However, it will be appreciated that other aquatic organisms could be restricted by the presently disclosed technology, for example, with different hydraulic targets depending on swimming capabilities.

The inventive subject matter describes an electrical barrier for the deterrence of fish having an electrical barrier with a computer system capable of executing a modified soft-start algorithm, the computer system further having a detector input and a switch output; a bio-electric fish proximity detector, the bio-electric fish proximity detector having a anode-cathode detecting pair input and a signal output, wherein said signal output is connected to the detector input; a time varying voltage source.

Aspects of the present disclosure involve hydraulic systems and methods for altering a flow of a body of water, such as a river, channel, and/or other flowing or uncontained bodies of water. In one aspect, a hydraulic system provides a velocity barrier for the impedance of aquatic organism migration. More particularly, the velocity barrier may be adapted based on the swimming capabilities of one or more aquatic organisms to impede migration. The aquatic organism may be one or more species of fish, such as species sea lamprey (Petromyzon marinus). The example implementations shown and described herein reference the restriction of the sea lamprey. However, it will be appreciated that other aquatic organisms could be restricted by the presently disclosed technology, for example, with different hydraulic targets depending on swimming capabilities.