A precast dam structure includes at least two precast segments coupled together via linkages and a flow path structure. The flow path structure defines a flow path having an intake port and a draft port and is associated with at least one of the at least two precast segments. The flow path structure is configured to provide a change in flow direction, either internally or externally, from the at least one of the at least two precast segments.

A fish passage system having flexible textile materials forming a conduit to transport fish across river barriers encountered during migration. The system can include modular support structures that can be independently secured to riverbeds to form conduit supports, dams, hydropower structures, and the like.

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 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.

The present invention is a fish passage system for use at dams. It may incorporate one or more reversible pump-turbines for controlling and generating power from downstream flow of water and fish and for pumping water and fish upstream. For low head embodiments the system may use water stored at above headwater elevation in lieu of a reversible pump turbine for moving fish and water from tailwater to headwater.

An arrangement on flowing bodies of water in the area of a transverse structure and/or water structure, in the form of a fish migration bypass (13) for transporting aquatic animals, in particular fish, between tail water (4) and head water (5), provided with a substantially vertical shaft (17). The water level in the shaft 17 is variable between the tail water and the head water level. A basket-like transport container (15), which can be moved in the shaft (17) and which is provided on the shaft for transport of aquatic animals, is equipped with floats (16), which are filled with air so that water rises/falls in the shaft (17) from the tail water (4) to the head water (5) and from the head water (5) to the tail water (4).

A method is provided for the artificial erosion of dammed bodies of water, wherein an average grain size distribution of sediments in the dammed body of water is determined across the ground surface of the dammed body of water. A sediment requirement for downstream water is determined, and as a result, at least one displacement of the sediments in the dammed body of water into the downstream water takes place in accordance with the sediment requirements for the downstream water. Advantageously, requirements regarding at least the quantity and grain size of the sediment for the downstream water are determined.

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.

A fish ladder for small-bodied fishes that is easily portable so as to enable installation and use in a given water course when needed, and relocation at other times. The fish ladder defines a channel with generally evenly spaced baffles in the channel disposed at about 45° angles to the channel bottom. The ladder includes a bracket that enables the ladder to be attached to any size, shape, and material of culvert or other drainage structure. The ladder is attached to the bracket with a hinge mechanism, so as to accommodate virtually any height of drop presented by small drainage structures. With extendable legs, a fish ladder according to embodiments of the invention is able to be installed in streams up to 6 feet deep. The ladder can be scaled so as to target passage of small-bodied non-game species such as minnows, while also passing larger game species as well.