Fish passage - Revision history

Jmdonev: 1 revision imported

2021-10-15T19:13:40Z

1 revision imported

← Older revision	Revision as of 19:13, 15 October 2021
(No difference)

energy>Jmdonev at 23:38, 27 May 2021

2021-05-27T23:38:09Z

← Older revision		Revision as of 23:38, 27 May 2021
Line 1:		Line 1:
	[[Category:Done ~~2015~~-09-05]]		[[Category:Done 2021-01-31]]
	[[File:John_Day_Dam_fish_ladder.jpg\|400px\|framed\|right\|Figure 1. A fish ladder at a hydraulic dam.<ref>Wikimedia Commons. (August 28, 2015). ''John Day Dam Fish Ladder'' [Online]. Available: https://upload.wikimedia.org/wikipedia/commons/0/0c/John_Day_Dam_fish_ladder.jpg</ref>]]		[[File:John_Day_Dam_fish_ladder.jpg\|400px\|framed\|right\|Figure 1. A fish ladder at a hydraulic dam.<ref>Wikimedia Commons. (August 28, 2015). ''John Day Dam Fish Ladder'' [Online]. Available: https://upload.wikimedia.org/wikipedia/commons/0/0c/John_Day_Dam_fish_ladder.jpg</ref>]]
			<onlyinclude>A '''fish passage''' is any device used to promote and regulate safe fish migration across [[hydroelectric facility\|hydroelectric facilities]]. If fish cannot migrate upstream beyond hydroelectric dams, populations can be impacted significantly.</onlyinclude><ref name="RE2">NOAA. (August 28, 2015). ''Fish Passage'' [Online]. Available: http://www.habitat.noaa.gov/ourwork/fishpassage.html</ref> Fish passages help to prevent harm from coming to river [[ecosystem]]s by providing fish and other forms of aquatic life safe methods of bypassing [[hydroelectric facilities]]. Types of fish passage include fish ladders, fish lifts, and juvenile bypass systems.

	~~<onlyinclude>A '''~~fish ~~passage''' is any device used to promote and regulate safe fish migration up and~~ downstream ~~from~~ [[~~hydroelectric facility~~\|~~hydroelectric facilities~~]]. ~~If fish cannot migrate~~ and ~~rear without interruption~~, ~~populations can significantly decrease~~.~~</onlyinclude>~~<ref ~~name="RE2"~~>NOAA. (August 28, 2015). ''Fish ~~Passage~~'' [Online]. Available: http://www.~~habitat~~.noaa.gov/~~ourwork~~/~~fishpassage~~.html</ref> Fish passages help to prevent harm from coming to river [[ecosystem]]s by providing fish and other forms of aquatic life safe methods of passing through [[hydroelectric facilities]]. Types of fish passage include fish ladders, fish lifts, and juvenile bypass systems.		Although fish can bypass dams when moving downstream by taking the path that [[water]] does through the [[hydro turbine\|turbines]], the spinning blades usually cause death or injury. Fish may also undergo stress and disorientation when pushed through the high [[velocity]] passage, which makes them susceptible to predators at the end of the passage. Though the safety of turbine designs have been improved through the use of rounded parts, they still pose significant risks for fish migration.<ref>NOAA. (August 28, 2015). ''New Turbines are Safer for Fish'' [Online]. Available: http://www.westcoast.fisheries.noaa.gov/fish_passage/about_dams_and_fish/turbines.html</ref>

	Although fish can bypass dams by taking the path that [[water]] flows through the [[hydro turbine\|turbines]], the spinning blades generally cause death or injury. Fish may also undergo stress and disorientation when pushed through the high [[velocity]] passage, which makes them susceptible to predators at the end of the passageway. Although turbine designs have been improved through the use of ~~rounded parts, there are still significant risks for fish to move through turbines.<ref>NOAA. (August 28, 2015). ''New Turbines are Safer for~~ Fish~~'' [Online]. Available: http://www.westcoast.fisheries.noaa.gov/fish_passage/about_dams_and_fish/turbines.html</ref>~~		==Types of Fish Passages==

	~~==Types of Fish Passages==~~
	~~There are a few main types of fish passages that allow fish to move up or downstream. They are outlined below.~~
	===Fish Ladder===		===Fish Ladder===
	A fish ladder is a structure that ~~allows~~ fish to climb to a higher elevation. ~~There are several different specific designs of fish ladders, but the overall construction remains the same. Fish ladders are made of a series of slopes and pools that resemble~~ a ~~flight of stairs. This long, slightly sloped (generally they have no more~~ than a 10% ~~incline)~~ stairway includes a series of pools known as weirs.<ref name="RE1">Office of Technological Assessment. (August 28, 2015). ''Upstream Fish Passage Technologies: How Well Do They Work?'' [Online]. Available: http://www.princeton.edu/~ota/disk1/1995/9519/951905.PDF</ref> These ~~weirs~~ allow fish ~~to have an area~~ to rest as they climb the ladder without ~~being pushed downstream. The goal of these is to prevent fish from experiencing too much stress when climbing the ladder.~~		A fish ladder is a structure comprised of a series of stepped slopes and pools that allow fish to climb to a higher elevation. Usually constructed at a less than 10% grade, this sloped stairway includes a series of pools bounded by small retention walls known as '''weirs'''.<ref name="RE1">Office of Technological Assessment. (August 28, 2015). ''Upstream Fish Passage Technologies: How Well Do They Work?'' [Online]. Available: http://www.princeton.edu/~ota/disk1/1995/9519/951905.PDF</ref> These pools allow fish to rest as they climb the ladder without having to constantly fight the current, helping to reduce stress and energy expenditure.

	~~To attract migrating fish~~ to the ~~ladder, it must accurately simulate downstream flow. By simulating downstream flow~~, ~~fish will naturally swim against this flow and climb the ladder. This natural flow and slight slope allow fish~~ to ~~move upstream~~ and ~~uphill to pass the dam safely, not being diverted through the dam itself~~.~~<ref name="RE1"/>~~

	Fish ladders pose issues for weaker or non-jumping species, as they are generally designed for stronger swimming fish or jumping fish such as trout and salmon.<ref name="RE1"/>		In order to attract migrating fish, the ladder must accurately simulate the river's downstream flow. By simulating this flow, fish will naturally swim up-current and climb the ladder<ref name="RE1"/>. Fish ladders pose issues for weaker or non-jumping species, as they are generally designed for stronger swimming fish or jumping fish such as trout and salmon.<ref name="RE1"/>

	===Fish Lift===		===Fish Lift===
	Fish elevators and locks are collectively known as fish lifts. Fish lifts ~~are used in certain special situations because they~~ are not species specific, nor are they flow dependent like fish ladders are. These lifts attract fish to a chamber filled with water at the downstream side of the hydroelectric facility and transport them beyond it.<ref name="RE1"/>		Fish elevators and locks are collectively known as '''fish lifts'''. Fish lifts are not species specific, nor are they flow dependent like fish ladders are. These lifts attract fish to a chamber filled with water at the downstream side of the hydroelectric facility and transport them over and beyond to the upstream side.<ref name="RE1"/>

	Similar to fish ladders, the lifts attract fish into a hopper or chamber with the use of flowing water, which guides the fish into the elevator. After a set amount of time or if a sufficient amount of fish has been detected in the chamber, the elevator will carry the contents up to the forebay level and release the fish onto the upstream side of the dam.<ref name="RE1"/>		Similar to fish ladders, the lifts attract fish into a hopper or chamber with the use of flowing water, which guides the fish into the elevator. After a set amount of time or if a sufficient amount of fish has been detected in the chamber, the elevator will carry the contents up to the forebay level and release the fish onto the upstream side of the dam.<ref name="RE1"/>

	Fish lifts have several benefits over the use of fish ladder technologies. ~~Specifically, fish lifts~~ tend to work better when large numbers of fish are migrating, or the migrating fish ~~cannot jump well and~~ move up ~~the latter~~. ~~However, there are some downsides~~ to ~~fish lifts. For example,~~ crowding can occur in peak migratory periods.<ref name="RE1"/> Although the usage of fish lifts may accommodate for a larger quantity and variety of species, ~~fish~~ lifts are ~~more~~ prone to failure and thus can lead to a higher operating and maintenance cost as well as time lost due to malfunctioning or maintenance.<ref>M. Larinier, F. Travade. (August 28, 2015). ''Fish Locks and Fish Lifts'' [Online]. Available: http://www.kmae-journal.org/articles/kmae/pdf/2002/04/kmae2002364s102.pdf</ref>		Fish lifts have several benefits over the use of fish ladder technologies. They tend to work better when large numbers of fish are migrating, or the migrating fish are not suited for leaping out of the water in order to move up a fish ladder. A downside to these systems is that crowding can occur during peak migratory periods.<ref name="RE1"/> Although the usage of fish lifts may accommodate for a larger quantity and variety of species, the lifts are prone to failure and thus can lead to a higher operating and maintenance cost as well as time lost due to malfunctioning or maintenance.<ref>M. Larinier, F. Travade. (August 28, 2015). ''Fish Locks and Fish Lifts'' [Online]. Available: http://www.kmae-journal.org/articles/kmae/pdf/2002/04/kmae2002364s102.pdf</ref>

	===Juvenile Bypass Systems===		===Juvenile Bypass Systems===
	~~This is a special~~ system ~~that~~ allows ~~juvenile~~ fish to move downstream from ~~hydroelectric dams while completely avoiding the turbine passage, which could otherwise cause death or injury~~. This system channels young or smaller fish into a ~~special~~ gatewell through the use of a [[fish screen]]~~. This gatewell is simply a small, upwards chute of water~~. From the gatewell, the small fish are collected and transported through a special channel from the turbine into the downstream reservoir.<ref>NOAA. (August 28, 2015). ''Juvenile Bypass Systems Help Fish Avoid Turbines'' [Online].Available: http://www.westcoast.fisheries.noaa.gov/fish_passage/about_dams_and_fish/juvenile_bypass_systems.html</ref>		A juvenile bypass system allows young fish to move across hydroelectric dams as they migrate downstream from their upstream spawning grounds. This system channels young or smaller fish into a small upwards current known as a gatewell through the use of a [[fish screen]]. From the gatewell, the small fish are collected and transported through a special channel from the turbine into the downstream reservoir.<ref>NOAA. (August 28, 2015). ''Juvenile Bypass Systems Help Fish Avoid Turbines'' [Online].Available: http://www.westcoast.fisheries.noaa.gov/fish_passage/about_dams_and_fish/juvenile_bypass_systems.html</ref>

			== For Further Reading ==
			For further information please see the related pages below:
			* [[Hydropower]]
			* [[Hydroelectricity]]
			* [[Hydrologic cycle]]
			* [[Environmental impacts of hydropower]]
			* [[Fish screen]]

	==References==		==References==
	{{reflist}}		{{reflist}}[[Category:Uploaded]]

J.williams: 1 revision imported

2015-09-03T18:22:35Z

1 revision imported

← Older revision	Revision as of 18:22, 3 September 2015
(No difference)

Jmdonev at 20:50, 28 August 2015

2015-08-28T20:50:06Z

New page

[[Category:Done 2015-09-05]]
[[File:John_Day_Dam_fish_ladder.jpg|400px|framed|right|Figure 1. A fish ladder at a hydraulic dam.<ref>Wikimedia Commons. (August 28, 2015). ''John Day Dam Fish Ladder'' [Online]. Available: https://upload.wikimedia.org/wikipedia/commons/0/0c/John_Day_Dam_fish_ladder.jpg</ref>]]

<onlyinclude>A '''fish passage''' is any device used to promote and regulate safe fish migration up and downstream from [[hydroelectric facility|hydroelectric facilities]]. If fish cannot migrate and rear without interruption, populations can significantly decrease.</onlyinclude><ref name="RE2">NOAA. (August 28, 2015). ''Fish Passage'' [Online]. Available: http://www.habitat.noaa.gov/ourwork/fishpassage.html</ref> Fish passages help to prevent harm from coming to river [[ecosystem]]s by providing fish and other forms of aquatic life safe methods of passing through [[hydroelectric facilities]]. Types of fish passage include fish ladders, fish lifts, and juvenile bypass systems.

Although fish can bypass dams by taking the path that [[water]] flows through the [[hydro turbine|turbines]], the spinning blades generally cause death or injury. Fish may also undergo stress and disorientation when pushed through the high [[velocity]] passage, which makes them susceptible to predators at the end of the passageway. Although turbine designs have been improved through the use of rounded parts, there are still significant risks for fish to move through turbines.<ref>NOAA. (August 28, 2015). ''New Turbines are Safer for Fish'' [Online]. Available: http://www.westcoast.fisheries.noaa.gov/fish_passage/about_dams_and_fish/turbines.html</ref>

==Types of Fish Passages==
There are a few main types of fish passages that allow fish to move up or downstream. They are outlined below.
===Fish Ladder===
A fish ladder is a structure that allows fish to climb to a higher elevation. There are several different specific designs of fish ladders, but the overall construction remains the same. Fish ladders are made of a series of slopes and pools that resemble a flight of stairs. This long, slightly sloped (generally they have no more than a 10% incline) stairway includes a series of pools known as weirs.<ref name="RE1">Office of Technological Assessment. (August 28, 2015). ''Upstream Fish Passage Technologies: How Well Do They Work?'' [Online]. Available: http://www.princeton.edu/~ota/disk1/1995/9519/951905.PDF</ref> These weirs allow fish to have an area to rest as they climb the ladder without being pushed downstream. The goal of these is to prevent fish from experiencing too much stress when climbing the ladder.

To attract migrating fish to the ladder, it must accurately simulate downstream flow. By simulating downstream flow, fish will naturally swim against this flow and climb the ladder. This natural flow and slight slope allow fish to move upstream and uphill to pass the dam safely, not being diverted through the dam itself.<ref name="RE1"/>

Fish ladders pose issues for weaker or non-jumping species, as they are generally designed for stronger swimming fish or jumping fish such as trout and salmon.<ref name="RE1"/>

===Fish Lift===
Fish elevators and locks are collectively known as fish lifts. Fish lifts are used in certain special situations because they are not species specific, nor are they flow dependent like fish ladders are. These lifts attract fish to a chamber filled with water at the downstream side of the hydroelectric facility and transport them beyond it.<ref name="RE1"/>

Similar to fish ladders, the lifts attract fish into a hopper or chamber with the use of flowing water, which guides the fish into the elevator. After a set amount of time or if a sufficient amount of fish has been detected in the chamber, the elevator will carry the contents up to the forebay level and release the fish onto the upstream side of the dam.<ref name="RE1"/>

Fish lifts have several benefits over the use of fish ladder technologies. Specifically, fish lifts tend to work better when large numbers of fish are migrating, or the migrating fish cannot jump well and move up the latter. However, there are some downsides to fish lifts. For example, crowding can occur in peak migratory periods.<ref name="RE1"/> Although the usage of fish lifts may accommodate for a larger quantity and variety of species, fish lifts are more prone to failure and thus can lead to a higher operating and maintenance cost as well as time lost due to malfunctioning or maintenance.<ref>M. Larinier, F. Travade. (August 28, 2015). ''Fish Locks and Fish Lifts'' [Online]. Available: http://www.kmae-journal.org/articles/kmae/pdf/2002/04/kmae2002364s102.pdf</ref>

===Juvenile Bypass Systems===
This is a special system that allows juvenile fish to move downstream from hydroelectric dams while completely avoiding the turbine passage, which could otherwise cause death or injury. This system channels young or smaller fish into a special gatewell through the use of a [[fish screen]]. This gatewell is simply a small, upwards chute of water. From the gatewell, the small fish are collected and transported through a special channel from the turbine into the downstream reservoir.<ref>NOAA. (August 28, 2015). ''Juvenile Bypass Systems Help Fish Avoid Turbines'' [Online].Available: http://www.westcoast.fisheries.noaa.gov/fish_passage/about_dams_and_fish/juvenile_bypass_systems.html</ref>

==References==
{{reflist}}