Also found in: Dictionary, Thesaurus, Wikipedia.
Related to Fishway: Fish ladders


(civil engineering)
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



in a hydroengineering complex, a structure enabling fish to pass upstream, mainly during the spawning migration. Fishways are divided into two basic groups: structures enabling fish to independently pass an obstacle (fish passes) and structures that move fish (locks and fish elevators).

Fish passes are channels through which water flows downstream at a speed making it possible for the fish to swim against the current. There are three basic types of fish passes: trough, pond, and ladder. Some trough passes have slight gradients, smooth walls, and a smooth bottom. The bottom and walls of others are fitted with projections. Another type of trough pass has incomplete partitions (in terms of depth and width).

Pond passes consist of a series of basins, where the fish can rest during their journey. The basins are connected by short channels or troughs. The passes usually are built in the banks, bypassing the dam.

Fish ladders are in the form of stepped troughs divided into a series of basins by cross-partitions having flotation openings. This type of fish pass has proved most effective for many different species of fish.

A dam on the Tuloma River (USSR) has a fish ladder for Atlantic salmon (height, 20 m; length, 513 m), and the McNary dam on the Columbia River (United States) has a ladder for salmon (height, 25 m; length, 610 m).

Fish locks in terms of operation are similar to ship locks. Ordinarily they have two adjacent chambers, each of which has gates separating the chambers from the upper and lower waters. The locks can operate under significant head. However, they require large amounts of water, and their fish-passing capacity is relatively low.

Fish elevators, which lift the fish in a moving flooded chamber or in a special net, operate according to the same principle as mechanical ship-lifting apparatus. Fish elevators, like fish locks, are usually located in separate piers of the dams. Also used as fishways are hydraulic fish elevators, floating fish-lifting devices, and, sometimes, ship locks and spillways of hydroelectric power plants.

It is advisable to locate fishways around the spillways. To guide the fish away from dangerous areas and toward the entrance of a fishway, guiding and protective nets and screens are set out. The subsequent descent downstream of the fish and their young is made possible through the use of all types of fish passes, hydraulic fish elevators, low- and medium-head spillway dams, ship locks, and the water channels of hydroelectric power plants equipped with adjustable-blade and mixed-flow turbines (with a large-diameter rotor, a slow turning speed, and significant clearance between the rotor and the stator). The designs for fishways in modern high-head hydroelectric projects are still insufficiently advanced.


Birznek, O. A., and Z. M. Kipper. Rybopropusknye sooruzheniia. Moscow, 1960.
Grishin, M. M. Gidrotekhnicheskie sooruzheniia. Moscow, 1968.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Fishways allow alewives to circumvent these obstructions by swimming over or around the dams.
A Numerical Study on Hydraulic Characteristics in the Ice Harbor- type Fishway , KSCE Journal of Civil Engineering, 16(2) 265-272.
Measurements were done in different horizontal plates and parallel to the floor (in depth of 20 cm and 60 cm), a network of 150 points as reference for measuring on each plate for each fishway pool.
In sum, the Ninth Circuit held that 1) the Conservancy lacked prudential standing to bring an APA challenge, and 2) the Ninth Circuit lacked jurisdiction over the Conservancy's claims that Defendants violated Washington's Fishway Law.
Fish and lamprey passage in a combined Denil and vertical slot fishway, Fisheries Management and Ecology 5: 31-44.
It leaves such matters to other statutes such as the Fishway Act (165) and the Anadromous Fish Act, (166) both discussed below.
However, a major factor concerning the design of a fishway is the migratory fishes' swimming capacity in terms of speed and endurance (Beach, 1984), which makes the dimensioning of efficient fishways in the formerly mentioned neotropical region practically impossible (Quiros, 1989).
The California law stated that dam owners "shall allow sufficient water at all times to pass through a fishway, or in the absence of a fishway, allow sufficient water to pass over, around or through the darn, to keep in good condition any fish that may be planted or exist below the dam." CAL.
In January, the administration's wildlife agencies mandated the strongest fishway prescriptions within their legal authority.
These are worthwhile projects and we acknowledge the leadership and commitment the Federal Government has shown here, especially in making the Hume-to-sea fishway financially viable and intensifying efforts to address salinity and other water quality problems.
The Parker River project improved a fishway for anadromous fishes with a more sophisticated Alaskan Steep Pass fish ladder.