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. The Big Blackfoot River restoration progress report for 2002 and 2003 . Fish populations; Fishes; Fishery management; Trout fisheries; Stream ecology; Blackfoot River (Mont. ). Photo I. Fish impinged on the outer portion of the screen against the screen in area Proper operation and maintenance of a fish screen is equally important to quality screen design (Nordlum 1996) in order to assure long-term effectiveness and fimction. In the Blackfoot River drainage, inadequate maintenance has reduced the effectiveness of many mechanical fish screens (paddlewheel and rotating drum). Because it has no

. The Big Blackfoot River restoration progress report for 2002 and 2003 . Fish populations; Fishes; Fishery management; Trout fisheries; Stream ecology; Blackfoot River (Mont. ). Photo I. Fish impinged on the outer portion of the screen against the screen in area Proper operation and maintenance of a fish screen is equally important to quality screen design (Nordlum 1996) in order to assure long-term effectiveness and fimction. In the Blackfoot River drainage, inadequate maintenance has reduced the effectiveness of many mechanical fish screens (paddlewheel and rotating drum). Because it has no Stock Photo
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Contributor:

Library Book Collection / Alamy Stock Photo

Image ID:

RHT921

File size:

7.1 MB (454.9 KB Compressed download)

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Dimensions:

1891 x 1321 px | 32 x 22.4 cm | 12.6 x 8.8 inches | 150dpi

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This image is a public domain image, which means either that copyright has expired in the image or the copyright holder has waived their copyright. Alamy charges you a fee for access to the high resolution copy of the image.

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. The Big Blackfoot River restoration progress report for 2002 and 2003 . Fish populations; Fishes; Fishery management; Trout fisheries; Stream ecology; Blackfoot River (Mont. ). Photo I. Fish impinged on the outer portion of the screen against the screen in area Proper operation and maintenance of a fish screen is equally important to quality screen design (Nordlum 1996) in order to assure long-term effectiveness and fimction. In the Blackfoot River drainage, inadequate maintenance has reduced the effectiveness of many mechanical fish screens (paddlewheel and rotating drum). Because it has no mechanical parts, the turbulent fountain screen requires less maintenance than conventional fish screens and is cheaper to install and use. The total cost of the entire modified turbulent fountain system including the head gate was $9,900, approximately 75% of the cost of self-powered paddlewheel driven fish screen and head gate of comparable flow capacity (Montana Fish, Wildlife and Parks data). While comparable in cost to electrically powered rotating drums of similar capacity, a turbulent fountain required lower maintenance at less expense. Throughout the three summers of use, the turbulent fountain required less manual cleaning than either traditional paddlewheel driven flat-plate screens or electrically powered rotating drums. With proper design and construction, a turbulent fountain fish screen, as an integrated diversion structure, can meet multiple objectives. These include: 1) volume control to an irrigation system and automatic removal of debris from a pipeline, 2) the elimination of entrainment into diversion ditches and the return of fish directly back to the stream immediately below the diversion point, 3) reduced impingement, 4) minimal screen maintenance, and 5) a cost-effective screening device. Unfortunately turbulent fountains have not been designed for volumes >0.15 m s although Bondurant and Kemper (1985) suggest designs for higher flows are possible. Re

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