Environmental issues in Puget Sound and River Irwell: Difference between pages

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{{Geobox|River
{{articleissues
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|POV = December 2007
| name = River Irwell
|copyedit = January 2007
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|citationstyle = October 2008}}
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{{seealso|Environmental issues in the United States}}
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The '''environmental health''' of '''[[Puget Sound]]''', [[Washington]] has a diverse and complex history related to a long, involved relationship with marine and freshwater [[ecosystem]]s. Population fluctuations in [[Salmonidae|salmonids]] can serve as indicators of environmental health.<ref>{{cite book|last=Montgomery|first=David R.|title=King of Fish: The Thousand-Year Run of Salmon|publisher=[[Westview Press]]|location=Boulder|date=2003}}</ref>
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| image = Irwell, Salford.jpg
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| image_caption = The River Irwell at [[Salford]], looking towards [[Manchester City Centre]]
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| country = England
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| discharge_location = Adelphi Weir
| discharge = 17.72
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| source_location = [[Cliviger]], [[Lancashire]]
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| mouth_location = [[River Mersey]], [[Salford]]
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<!-- *** Tributaries *** -->
| tributary_left = [[River Croal|Croal]]
| tributary_left1 =
| tributary_right = [[River Roch|Roch]]
| tributary_right1 = [[River Irk|Irk]]
| tributary_right2 = [[River Medlock|Medlock]]
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<!---Start of article--->
== Puget Sound industry ==
The '''River Irwell''' is a [[river]] flowing through the [[Irwell Valley]] in the counties of [[Lancashire]] and [[Greater Manchester]] in England. It is one of several rivers that helped facilitate the [[Industrial Revolution]] in [[North West England]], as a result of which it became severely polluted during the 19th century.
Puget Sound, Washington is a body of land lying east of [[Admiralty Inlet]], through which ocean waters reach inland some {{convert|50|mi|km}} from the [[Pacific coast|Pacific Coast]] to provide all-weather ports for ocean-going ships at [[Seattle]], [[Tacoma]] and [[Olympia, Washington|Olympia]]. The waterway is a complex and intricate system of [[Channel (geography)|channels]], [[inlet]]s, [[Estuary|estuaries]], [[embayment]]s and [[island]]s. Industries in this area include aerospace and military, biotechnology, fishing, electronics and computers, forest products, marine industries, telecommunications, transportation and commerce, and [[value-added]] industries.<ref>{{cite web|url=http://www.choosewashington.com/industries/|title=Washington State Community, Trade, and Economic Development. Business and Project Development: Top Industries|accessdate=2006-07-13}}</ref>


The river's [[Source (river or stream)|source]] is at Irwell Springs on Deerplay Moor, about {{convert|1.5|mi|km}} north of [[Bacup]], in the parish of [[Cliviger]], Lancashire. The Irwell flows through (and separates) the city centres of [[Manchester]] and [[Salford]], before joining the [[River Mersey]].
Many of Puget Sound’s industries rely upon natural resources found in the surrounding ecosystem. For example, [[oysters]], [[salmon]], [[clams]], [[herring]], [[trout]], [[yellow perch]] and [[sole]] can be harvested from Puget Sound’s oceans and riverbeds, supporting a healthy fishing and shellfish industry.<ref>{{cite web|url=http://wdfw.wa.gov/factshts/hatcheries.htm|title=Washington State Department of Fish and Wildlife: Hatchery Fact Sheet|date=2000|accessdate=2006-08-09}}</ref><ref>{{cite web|url=http://www.choosewashington.com/industries/detail.asp?i=3|title=Marine Services in Washington State|accessdate=2008-10-04}}</ref> Fish farming (fish [[aquaculture]]) is also growing in the Puget Sound, as is the farming of shellfish, such as [[geoduck]]. Washington state is the second largest U.S. seafood producer, after [[Alaska]], and ranks first or second in oyster production in the nation. For the west coast, Washington state provides 86% of the bivalve market.<ref>{{cite web|url=http://www.choosewashington.com/industries/detail.asp?i=3|title=Marine Services in Washington State|publisher=Washington Public Ports Association|accessdate=2008-10-04}}</ref>


== Course ==
Some early industries<!-- What time frame? --> used improper storage methods for dangerous chemicals, such as [[arsenic]]. As a result, areas of soil and aquatic land in Puget Sound are being managed under the Comprehensive Environmental Response, Compensation and Liability Act ([[CERCLA]]).<ref name="02-35">{{cite news|title=Toxics Cleanup Program|date=2002|work=News Release 02-35|publisher=Washington State Department of Ecology|accessdate=2008-10-04}}</ref>
Standards for the storage and discharge of industry chemicals have improved, and Puget Sound remains vital to the industries that depend upon it, such as shipping [[ports]]. Ports in Washington state are diverse. Governed as municipalities, Washington ports operate shipping terminals, marinas, docks, and associated infrastructure, such as roads, railroads and parks. The fastest-growing part of Washington ports is industrial development.<ref name="02-35"/><ref>{{cite web|url=http://www.washingtonports.org/|title=Washington State Public Ports Association|date=2006|accessdate=2006-07-13}}</ref>


The '''River Irwell''' is about {{convert|39|mi|km}} in length.<ref>[http://www.chalk-ndc.info/ndc_may_jun041-2.pdf NDC newletter issue 9 May-June 04] Retrieved on [[2008-03-21]]</ref> Rising on the moors above [[Cliviger]] the Irwell flows south through [[Bacup]], [[Rawtenstall]], [[Ramsbottom]] and [[Bury]] before merging with the [[River Roch]] near [[Radcliffe, Greater Manchester|Radcliffe]]. Turning west it is joined by the [[River Croal]] near [[Farnworth]] and runs south east through [[Kearsley]], [[Clifton, Greater Manchester|Clifton]] and [[Agecroft]] then [[meander]]s around [[Broughton, Greater Manchester|Lower Broughton]] and [[Kersal]], Salford Crescent and the centre of Manchester, joining the rivers [[River Irk|Irk]] and [[River Medlock|Medlock]]. Again turning west, from Salford, it meets the Mersey south of [[Irlam]], where the route of the river was altered in the late 19th century to form part of the course of the [[Manchester Ship Canal]].
== Urbanization and population in Puget Sound ==
The Puget Sound region has been growing rapidly. According to the [[Puget Sound Regional Council]] (PSRC), a board that plans for [[growth]] in the four central counties of the area ([[Kitsap County, Washington|Kitsap]], [[Pierce County, Washington|Pierce]], [[Snohomish County, Washington|Snohomish]] and [[King County, Washington|King]] counties), the combined population of these counties was nearly 3.4 million residents in 2003. These counties forecast an increase to 4.99 million residents by the year 2040 for the central Puget Sound region alone.<ref name="PSRC">{{cite web|url=http://www.psrceis.org/Content/10000/VISION_202020_HOME.html|title=Vision 2020|date=2006|publisher=Puget Sound Regional Council|accessdate=2008-10-04}}</ref>


== Natural History ==
Between 1970 and 2000, the region increased by 1.3 million people. The PSRC predicts that between 2000 and 2020, the region will increase by 1.7 million people. Another change Puget Sound faces involves [[demographics]] of its population. The segment of population ages 65 and older is projected to increase by 150 percent, making up 17 percent of the total population by 2040. The [[workforce]], which makes up the segment ages 20–64, is expected to decline, with the age group 20 and younger shrinking, as fewer [[households]] are of childbearing years.<ref name="PSRC"/>
Before the [[Industrial Revolution]] the Irwell was well stocked with fish, and the people who lived in the houses near [[Manchester Cathedral]] drew flagons of water from it for drinking and other domestic purposes. However, in the 19th century chemicals from the expanding industries poured into the river in increasing amounts. These pollutants were fatal to fish, the last of which were seen about 1850.<ref>Bracegirdle p.19</ref>
[[Image:The Cliff, Broughton.jpg|thumb|right| The Irwell flowing past The Cliff through Kersal Dale Country Park]]


Despite its industrial past, [[fish stock]]s in the River Irwell are improving and [[brown trout]] are becoming an increasingly common sight. [[Coarse fishing|Coarse fish]] now predominate throughout the river's course and beyond into the [[Manchester Ship Canal]]. [[Water fowl]], [[herons]] and [[cormorant]]s are also resident on the river. New problems became apparent with the redevelopment of the [[Salford Quays]] area of the [[Manchester Ship Canal]]. Years of runoff from sewers and roads had accumulated in the slow running waters of this area and decomposition of the organic matter was causing [[oxygen depletion]] of the water. In 2001 a compressed air injection system was introduced, which raised the oxygen levels in the water by up to 300%. The resulting improvement in water quality has led to an increase in the number of invertebrate species, such as freshwater [[shrimp]], to more than 30. [[spawn (biology)|Spawning]] and growth rates of fish species such as [[roach]] and [[perch]]
Under the [[Growth Management Act]] (GMA), local governments plan, coordinate, and manage for growth in Washington state, while protecting natural resources and public interests. The GMA requires local governments to develop long-term comprehensive plans for land uses in their [[jurisdiction]]s. Plans must be coordinated with surrounding counties and be approved by a regional board. The local government must also develop a [[shoreline]] master plan, if the jurisdiction contains a "shoreline of statewide significance". Finally, as part of the GMA, local governments must address sensitive fish and wildlife areas through [[Critical Area Ordinances]] (CAOs).<ref>{{cite book|title=Revised Code of Washington|chapter=Chapter 36.70A RCW: Growth management — planning by selected counties and cities}}</ref>
have also increased to such an extent that they are now amongst the highest in England.<ref>{{cite web|url= http://www.mangeogsoc.org.uk/egm/5_1.pdf|accessdate=2007-12-11|date=2003-08-21|format=pdf|title= Exploring Greater Manchester&nbsp;— a fieldwork guide: The fluvioglacial gravel ridges of Salford and flooding on the River Irwell|author= Hindle, P.(1998)|publisher=Manchester Geographical Society}} p.18 </ref>


Two [[List of Sites of Special Scientific Interest in Greater Manchester|Sites of Special Scientific Interest (SSSIs)]] are located close to the banks of the Irwell where it flows through [[Moses Gate Country Park]], between [[Prestolee]] and [[Little Lever]]. The first is [[Nob End]], an 8.8 hectare (21.7 acre) site which has been designated because of its biological interest, based on the predominance of flora typical of [[limestone]] [[grassland]] including some nationally rare herbs and orchids. Nob End is also designated as a [[Local Nature Reserve]]. This alkaline soil habitat was formed by the dumping of toxic alkaline waste from the [[Leblanc process]] between 1850 and 1870, which subsequently weathered into [[calcium carbonate]], permitting the establishment of chalk-loving vegetation. Limestone grassland is not normally found in Greater Manchester, and many of these species are not found elsewhere in the county.<ref>{{cite web | title=Nob End citation sheet | url=http://www.english-nature.org.uk/citation/citation_photo/1003648.pdf | work=English Nature | accessdate=2007-02-24|format=PDF}}</ref><ref>http://biohorizons.oxfordjournals.org/cgi/content/full/1/1/61 Retrieved on [[2008-05-18]]</ref> The second site is Ashclough, a site of geological interest that is described below in the Geology section. These two SSSIs are among the [[List of Sites of Special Scientific Interest in Greater Manchester|21 found in Greater Manchester]].
==Hood Canal Hypoxia==


In Salford the river flows through [[Clifton Country Park]] and Kersal Dale Country Park, both of which have been designated as a [[Local Nature Reserve]]s (LNRs).<ref>http://www.salford.gov.uk/leisure/parks/countryparks/thecliff.htm Retrieved on [[2008-01-28]]</ref>
[[Hood Canal]] is a long, narrow and deep [[fjord]]-like body of water. Preliminary hypotheses discuss different contributing factors potentially influencing low-oxygen conditions ([[hypoxia (environmental)|hypoxia]]) in Hood Canal. One overriding factor is the underwater [[topography]] of the Canal. The deepest parts of the [[Canal]] are more than {{convert|600|ft|m}} deep, but at the entrance is a sill that is only {{convert|150|ft|m}} deep. Inlets or [[bays]] with this constricted shape often experience sluggish water exchange. The Hood Canal Dissolved Oxygen Program<ref>{{cite web|url=http://www.hoodcanal.washington.edu/|title=Hood Canal Dissolved Oxygen Progam - Integrated Assessment and Modeling Study|date=2006|publisher=University of Washington, Applied Physics Department|accessdate=2008-10-04}}</ref> and the [[United States Geological Survey|United States Geological Service]] (USGS) are studying Hood Canal circulation, trying to model the [[tidal]] circulations and [[salinity]] distribution patterns between the Canal and Admiralty Inlet.<ref>{{cite journal|last=Josberger|first=E.G.|coauthors=R.T. Cheng|date=2005|title=Modeling tidal circulation and freshwater mixing in Hood Canal, Washington|publisher=USGS Modeling Conference, Port Angeles, Washington, November 15-17, 2005}}</ref> The HCDOP discusses a number of other factors that when combined with the constrictive shape, could also influence hypoxia in Hood Canal:<ref>{{cite journal|last=Newton|first=Jan|date=2006|title=Low Dissoved Oxygen in Hood Canal|publisher=University of Washington, Applied Physics Laboratory|url=http://www.hoodcanal.washington.edu/aboutHC/scienceprimer.jsp?perPage=1&startIndex=0&View=&keyword=EDUPPT}}</ref>


== Geology ==
#[[Pacific Ocean]] marine water may be entering with a lower oxygen content than historically received
[[Image:Red sandstone on the Irwell.jpg|thumb|left|A tributary of the Irwell flowing over the [[new red sandstone]] at [[Clifton, Greater Manchester|Clifton]]]]
#Marine water may be entering at a density lighter than needed to flush out Hood Canal quickly or effectively
The Irwell is all that remains of the shallow seas that covered most of south-east Lancashire in the [[Upper Carboniferous]] era when deposits of mud and sand were laid down. These later became beds of [[shale]]s and [[sandstone]]s alternating with layers of [[gritstone]]. There are also beds of [[new red sandstone]] and Manchester [[Marl]]s.<ref> Bracegirdle pp 15,16</ref> The [[glaciers]] of the [[Pleistocene]] period further shaped the landscape and then retreated, leaving behind deposits of sand, pebbles and [[boulder clay]] that formed the [[fluvioglacial landform|fluvioglacial ridges]] of the [[Irwell Valley]].<ref>{{cite web|url= http://www.mangeogsoc.org.uk/egm/5_1.pdf|accessdate=2007-12-11|date=2003-08-21|format=pdf|title= Exploring Greater Manchester&nbsp;— a fieldwork guide: The fluvioglacial gravel ridges of Salford and flooding on the River Irwell|author= Hindle, P.(1998)|publisher=Manchester Geographical Society}}</ref> Ashclough, a 5.8 hectare (14.3 acre) site which comprises the steep banks of the river between Prestolee and Little Lever, has been designated a [[List of Sites of Special Scientific Interest in Greater Manchester|Site of Special Scientific Interest (SSSI)]] because of its geological interest, primarily because it is the best site in the area displaying [[Marine band (geology)|Ashcough Marine Band]] and its associated strata. Ashclough is a site of national importance for interpreting the [[coal measure]] [[paleogeography]] of Great Britain.<ref>{{cite web | title=Ashclough citation sheet | url=http://www.english-nature.org.uk/citation/citation_photo/1003262.pdf | work=English Nature | accessdate=2007-02-24|format=PDF}}</ref>
#[[Riverine]] freshwater input as changed—increased or decreased—altering the [[stratification]] of Hood Canal and have competing effects on marine water input
#[[Organic material]] input may have increased
#Light input may have increased ([[algae]] growth increases with light, as well as organic nutrient input)
#Wind currents may have altered water column [[circulation]]


== History ==
The picture surrounding hypoxia in Hood Canal is complex; research models are pointing to more than one contributing factor. [[Nutrient]] level is a large issue due to the human impact. The supply of nutrients, primarily [[nitrate]]s, to the [[Photic zone|euphotic zone]], is thought to impact levels of dissolved oxygen. Nutrients feed algae, which under the right conditions "bloom" and then die and decompose; the entire process requires a large amount of oxygen. This decreases the oxygen in the water column, lowering the dissolved [[oxygen]] level.{{facts|date=October 2008}}
[[Image:River Irwell Manchester.JPG|thumb|rght|The River Irwell divides the cities of [[City of Salford|Salford]] and [[Manchester]].]]
[[Image:Irwell between manchester and salford.jpg|thumb|right|The Irwell at night]]
The origins of the name Irwell are uncertain but many accept the [[Anglo-Saxon]] origin: Ere-well, meaning "hoar or white spring".<ref>Bracegirdle p.24</ref>


The first known human settlements were those of the [[Celt]]ic tribe, the [[Brigantes]], who farmed the uplands and lower reaches of the river. In 79 AD the [[Roman Empire|Romans]] conquered these tribes, built forts at the confluences of the Irwell and the rivers [[Irk]] and [[River Medlock|Medlock]], calling the town [[Mamucium]].<ref>Bracegirdle pp.16,17</ref> They also built a ford with rectangular stone blocks at Cornbrook, which is thought to be the first man-made structure to span the river.<ref> Brereton p.6</ref> and built their villas along the river. For four hundred years the [[Pax Romana]] brought peace, but the Romans withdrew in 410 AD leaving the tribes to be overun by the [[Saxons]] who renamed the town Manigceastre. The Danes seized, and all-but destroyed, Manigceastre and the tribes were dispersed or absorbed by the Danes. The [[Danelaw]] ruled until 920 AD when the Norsemen were expelled by [[Edward the Elder]].<ref> Bracegirdle p.18</ref><ref>{{cite book| last = Parkinson-Bailey | first = John J | authorlink = John J Parkinson Bailey | title = Manchester: An Architectural History | publisher = Manchester University press | location = Manchester| pages = p2 | isbn = 978-0719056062 }}
There are both natural and man-made sources of nutrients. The primary natural source is in ocean water that flushes Hood Canal. Man-made sources include leaking [[septic]] systems, storm water runoff, agriculture and various other sources. The presence of nutrients leads to algae growth, which consumes oxygen when the algae die and decompose, contributing to the low oxygen conditions in these waters.{{facts|date=October 2008}}
</ref>


In the [[Middle Ages]] the town, which was now known as Manceastre (later to become [[Manchester]]), grew and prospered and trading vessels plied along the river.<ref> Bracegirdle p.18</ref>
Another factor mentioned by the HCDOP is the influence of the ocean water. The ocean water that enters Hood Canal is like most [[estuaries]]: fresh, warm water flow out at the surface and is replaced by cold, salty water at depth. The cold, salty ocean water that enters Hood Canal comes into Puget Sound from the open ocean and has not recently been in contact with the atmosphere. As a result, this water is initially somewhat depleted in oxygen.{{facts|date=October 2008}}


During the Industrial Revolution factories, mills and terraced hovels grew up along the river banks. Edward Corbett, the Borough Engineer of Salford wrote in his book ''The River Irwell'' published in 1907, that his father had told him that, about 1819, he had seen from the New Bailey bridge, (now Albert Bridge) in the centre of Manchester "large shoals of fish, chiefly gudgeon but also other fish, were rising to the flies." Chemicals that were dumped in the river such as gas-tar, gas-lime and ammonia water were fatal to the fish and by 1850 stacks had all disappeared. In 1860 the Irwell was described as "almost proverbial for the foulness of its waters; receiving the refuse of cotton factories, coal mines,print works, bleach works, dye works,chemical works, paper works, almost every kind of industry."<ref> Bracegirdle pp.19</ref> In the Victorian era passenger trips along the River Irwell from landing stages such as the ones at [[Manchester Cathedral Steps]], were popular. "Sailings to Pomona Gardens were very popular with courting couples, who liked to watch the eel-catchers, admire views of Trafford Park Woodlands, and gaze at the peaceful farms and orchards. But the increasing smells from the river stopped it all".<ref>{{cite book
Finally, seasons play a role. The warmer temperatures, longer days, and lower winds change flushing conditions. Low oxygen conditions are at their worst in the late summer, after several months of limited flushing and maximum [[plankton]] production near the surface. In some years, oxygen becomes sufficiently depleted that animals cannot survive. These kills may occur either locally or over a wide area.<ref>{{cite web|url=http://www.hoodcanal.washington.edu/|title=Hood Canal Dissolved Oxygen Program|accessdate=2008-10-04}}</ref>
| last =
| first =
| authorlink =
| coauthors =
| title = Greater Manchester: 125 Years Images from the Manchester Evening News
| publisher = The Breendon Books
| year = 1993
| location =
| pages = 21
| url =
| doi =
| id =
| isbn = 1873626673}}</ref> The [[List of Acts of Parliament of the United Kingdom Parliament, 1860-1879|Rivers Pollution Prevention Act 1876]] was designed to solve this problem, but it was largely ineffective. It did however lay the groundwork for the more draconian legislation which followed.


Since the late 19th century many attempts have made to improve the quality of the water in the Irwell. In 1891 the Mersey and Irwell Joint Committee was formed. This body ordered local authorities to provide [[sewage treatment]] facilities and industrial concerns were told to use the best practical means of preventing pollution. In 1939 this body was superseded by the Lancashire Rivers Board, but wartime conditions brought about further deterioration of the river. In 1951 the Rivers (Prevention of Pollution) Act was passed and this board disappeared to be replaced by the Mersey River Board, which was replaced in turn by the Mersey and Weaver River Authority in 1965.
==Eelgrass==
Beds of [[Eelgrass]] (''Zostera marina'') provide a vital link in the nearshore foodweb, creating underwater [[forests]] for [[biota]] such as [[salmon]], [[herring]], [[sand lance]], and numerous invertebrates.<ref>{{cite web|url=http://www.ecy.wa.gov/programs/sea/pugetsound/species/detritus.html/|title=Puget Sound Beaches, Neashore Food Web|date=2006|publisher=Washington State Department of Ecology}}</ref> Eelgrass is an underwater grass that thrives in [[Marine (ocean)|marine]] and [[estuarine]] water bottoms and spreads through [[rhizomes]], or roots. It has been estimated by the State Department of Natural Resources that Puget Sound is occupied by approximately 26,000 acres (105 km²) of eelgrass.<ref>{{cite web|url=http://www.dnr.wa.gov/ |title=Washington State Department of Natural Resources}}</ref> Research has shown that eelgrass beds in Puget Sound can be found in two different [[habitat (ecology)|habitats]]: flats, which can be described as either large shallow [[bays]] or small "pocket" [[beaches]], and in fringe beds along steep shorelines.<ref name=eelgrass>{{cite web|url=http://www2.wadnr.gov/nearshore/research/projectpages.asp?pagename=eelgrass_page1&id=8/|title=The Submerged Vegetation Monitoring Program|publisher=Washington Department of Natural Resources, Nearshore Program|accessdate=2006-08-08}}</ref>


A report in the ''Manchester Evening News'' in 1971 said that Bury Angling Society had signed an agreement with Bury Corporation giving them fishing rights along four miles of the river between Summerseat and Radcliffe. The secretary of the society was quoted as saying:
Eelgrass beds provide nutrients and shelter for various biota in Puget Sound such as salmonids. As eelgrass and other seagrasses decay, it combines with other dead matter. This rich [[detritus]] is a staple for [[invertebrates]], which are fed upon by salmonids, [[birds]], and other predators. Eelgrass functions as a protective cover from the predators for juvenile salmon and as a nursery for [[herring]] that deposit eggs among bed. Herring, in turn, are an important food source for juvenile and adult salmon.<ref name=nearshore>{{cite web|url=http://www2.wadnr.gov/nearshore/textfiles/pdf/2003_2004_SVMP_report.pdf/|title=Submerged Vegetation Monitoring Report|date=July 2005|publisher=Washington State Department of Natural Resources|accessdate=2006-08-08}}</ref>
<blockquote>
Extensive tests have been carried out on fish we put in the river and we are satisfied that the water will support fish life. Roach and perch have already been caught and we have had no reports of any ill-effects. There is no doubt the pollution is clearing. It will be a long job, but we are sure there is a future for angling in the river.
</blockquote>
The report went on to say that the society "intends to carry out stocking operations soon."<ref>''Manchester Evening News'' 3 December 1971</ref>


It was reported in the ''Manchester Evening News'' in 1972 that tiddlers had been seen swimming in the "notorious inky Irwell" near [[Peel Park, Salford]]. The Deputy chief water quality officer for Salford, Mr. Eric Harper, was quoted as saying:
During low [[tide]], eelgrass beds shelters other small animals from extreme temperatures, and in tideflats the beds act as a sponge for moisture.<ref name=nearshore/>


<blockquote>
Eelgrass monitoring is conducted throughout Puget Sound using random sampling under the Submerged Vegetation Monitoring Program, Washington Department of Natural Resources, Nearshore Program.<ref name=eelgrass/> Results for 2003 – 2004 were posted in 2005. Many eelgrass populations were holding steady, but sharp declines were noted in five shallow bays in the San Juan Islands and 14 smaller sites in the greater Puget Sound. Eelgrass throughout the entire Hood Canal showed a steady decline.<ref>{{cite web|url=http://www.psat.wa.gov/Publications/soundwaves/spring_sw06/science_news_eelgrass.htm|title=Eelgrass Study Brings Good and Bad|date=2006|publisher=Puget Sound Action Team|accessdate=2006-08-08}}</ref>
"Ten years ago, any fish getting as far down as Salford would have been killed almost immediately by the pollution in the water. Although the river there is now a great deal better than it has been for 100 years, fish will probably not be able to live long. These had probably got into the main river from small streams flowing into the Irwell. But I think it is real progress."
</blockquote>
Mr Harper went on to say that the Irwell had been well stocked with fish along its whole length 100 years ago but refused to guess when it would reach the same state again.<ref> ''Manchester Evening News'': "Tiddlers give new hope for cleaner "inky Irwell" but it will be a long time ahead. 25 November 1972</ref>


In 1974 all the river authorities were merged into the Regional Water Authorities.<ref> Bracegirdle pp. 153-155</ref> In the 1974 annual report of the [[North West Water|North West Water Authority (NWWA)]] it was said that that the river "once internationally famous, or infamous as the epitome of river pollution, is now in a much better state as compared with its condition at the time of a special survey carried out nine years ago."<ref>''Salford City Reporter'' "Notorious" river Irwell could become a pleasant stream. 1974 page 7 (date unknown)</ref> This was reported in an article in ''The Manchester Evening News'' on 26 October of that year which went on to say:
A number of reasons contribute to the decline in eelgrass population, including, but not limited to:<ref name=eelgrass/>
<blockquote>
During nine years of pollution control work reviewed by the North West Water Authority, the biggest improvement had been in the Bolton District, where effluent from five dilapidated sewage plants and two paper mills were now being treated at the Ringley Fold Works [but] there has been little reduction in pollution from the river Roch. At Bacup the headwater of the irwell is discoloured by ochre deposits from a disused mine but work is being done to stop the ochre seepage. Fish do exist in the stretch between Rossendale and Bury and fish are to be introduced in stretches between Radcliffe and Manchester. However, it is feared that it will be many years before fish will be able to breed freely in the river
<ref>''Manchester Evening News'' Fishing in the Irwell&nbsp;— after 100 years 26 October 1974</ref></blockquote>


In 1980 a scheme for improving the stretch of the river for various forms of boating between Littleton Road and Adelphi Weir, in Salford, was included in Greater Manchester Policy Committee's capital programme for 1981/2. County Councillors at a recent committee meeting had criticised the state of the river, with the councillor for Oldham calling it "quite revolting and horrible". A spokesperson for the NWWA said that, although the river had a reputation for being polluted it was getting much better, but it still hadn't reached a state where they would be satisfied. She added that tests were being carried out to show the improved cleanliness of the Irwell and that 600 trout had recently been put in the river at [[Summerseat]], near Bury. The proposals were welcomed by Salford University and Agecroft Rowing club with the University saying that they would like to use the stretch for their boat race.<ref>''Salford City Reporter'' Sailing down the Irwell on a Sunday afternoon 19 September 1980</ref> Later that year, it was reported that hundreds of trees and shrubs were to be planted along the banks of the Irwell between Broughton and Pomona Dock, in a £650,000 "green finger" scheme to to "bring the countryside into the heart of industrial Salford"<ref>''Manchester Evening News'' Irwell revamp at £650,000 1 November 1980</ref> The dossier outlining the scheme, prepared by Salford's Technical Services Officer, emphasised the "bleak character" of the Irwell Valley with "many constructions by the river that are decaying and rotting" and said "the main problems are caused by an excess of ammonia and a high organic content from sewage effluents which discharge into the water upstream". The report recommended that "even more support should be given to the NWWA in their pollution control of the River Irwell"<ref>''West Manchester News'' Improvement scheme looks a winner 14 November 1980</ref>
#Lack of appropriate [[Substrate (marine biology)|substrate]] to grow upon
#Lack of or poor-quality light impacting [[photosynthesis]]
#Changes in [[climate]] impacting [[Ocean current|currents]], water temperature, water quality
#Nutrient input, spurring algae growth, reducing light and oxygen availability
#[[Sediment]] input, reducing light availability/quality
#Physical alteration of the shoreline, potentially increasing [[wave]] energy, and/or altering substrate in the nearshore area


During the 1980s sightings of fish in the Irwell as far downstream as the centre of Manchester were being reported in local newspapers. In February 1981 the ''Manchester Evening News'' reported that "10 Jacksharps about two inches long" had been spotted by a site manager working on the [[Mark Addy]] public house being built on New bailey Street on the border of Manchester and Salford.<ref>Manchester Evening News Fish in the Irwell...it's true! 5 February 1981</ref> Plans for using the river for recreation were also coming to fruition as it was reported that, on the May Bank Holiday in 1982, the first pleasure cruise of the 20th Century would leave from the New Bailey Landing Stage outside the Mark Addy public house as part of a three day experiment to see if river cruises could be a success.<ref> ''Manchester Evening News'' As Salford's sailors get ready to cruise down the Irwell 23 April 1982</ref> Then, in 1983, more than 100 canal and river boats rode the flooded river for the Greater Manchester Waterways Festival, an event aimed at showing how pleasure boating could "transform the bleak waterway in the heart of Manchester"<ref>''Manchester Evenng News'' Tide turns for the Irwell 12 September 1983</ref>
The Puget Sound Conservation and Recovery Plan (2005 – 2007) outlines a number of goals for improving management and health of the state's eelgrass beds. These include increasing protection over eelgrass beds on state-managed aquatic lands, and developing a statewide "seagrass management conservation plan" to be used by local, state and federal agencies.<ref>{{cite web|url=http://www.psat.wa.gov/Publications/priorities_05/Priorities_05_review.htm/|title=Puget Sound Conservation and Recovery Plan}}</ref>


Since then there has been a gradual improvement in water quality,<ref>{{cite web| last = Anon | title = Urban Regeneration in Manchester: Tranforming the “Dark River Irwell”|publisher = Environment Agency |url= http://www.merseybasin.org.uk/page.asp?page=1&pagesize=5&confirmed=1&id=2837&docid=190 -| format = pdf| accessdate = 2008-04-24 |p.5}}</ref> and today wildlife is returning to the Irwell.
==The evolution of Pacific salmon==
Current salmonids arose from three lineages: [[Whitefish]] (''Coregoninae''), [[graylings]] (''Thymallinae'') and the [[char]], [[trout]] and [[salmon]]s (''Salmoninae''). While authors may differ on minute details, generally it is accepted that all three lineages share a suite of derived traits indicating a [[monophyletic]] group (McPhail in Stouder, et al, 1997).


== Mark Addy ==
''Salmonidae'' first became evident in the middle [[Eocene]], with the [[fossil]] ''Eosalmo driftwoodensis'' (discovered in Driftwood Creek, central British Columbia). This fossil shares traits found in the ''salmoninae'' lineage, but also whitefishes and graylines. Hence, ''E. driftwoodensis'' is an archaic salmonid, representing an important stage in salmonid evolution (McPhail in Stouder, et al, 1997).


One of the most famous characters associated with the river was [[Mark Addy (Albert Medal)|Mark Addy]], who was born in a [[tenement]] on The Parsonage near Blackfriars Bridge in [[Manchester]], known as Stage Buildings. His father owned several racing boats and pleasure craft for hire on the river and, even before he learned to swim, young Mark had already saved two people from the water, one by floating out on a plank and the other by wading up to his neck in the river. He became a strong swimmer and, after he married, acquired a tavern on the [[Salford]] side of the river. Whenever anyone was in difficulties the cry would go up "Bring Mark Addy" and he would race to rescue them. He was awarded a number of medals including the gold and silver medals from the Humane Society for the [[Hundred of Salford]], and the [[Royal Humane Society]]'s bronze medal. In 1878 he became the only civilian ever to be awarded the [[Albert Medal (lifesaving)|Albert Medal (first class)]],<ref name="Nicholls2004P64">Nicholls (2004), p.&nbsp;64.</ref> which was later superseded by the [[George Cross]] as the highest civilian or non-combat gallantry award in the [[British honours system]].<ref>[http://www.iwm.org.uk/server/show/ConWebDoc.940 Imperial War Museum: The George Cross] retrieved on [[2008-08-27]]</ref>
A gap appears in the salmonine fossil record after ''E. driftwoodensis'', until the late Miocene (~7 m.y.a.) Trout-like fossils appear in [[Idaho]], in the [http://www.sou.edu/aaaspd/TableContents/LateCenHist.pdf/ Clarkia Lake beds]. Several of these species appear to be ''[[Oncorhynchus]]'' - the current family for trout, char and Pacific Coast salmon. The presence of these species so far inland established that ''Oncorhynchus'' was not only present in the Pacific drainages before the beginning of the [[Pliocene]] (~5-6 m.y.a.), but also that rainbow, [[cutthroat]] and Pacific salmon lineages had diverged before the beginning of the Pliocene. Consequently, the split between ''Oncorhynchus'' and ''[[Salmo]]'' (Atlantic salmon) must have occurred well before the Pliocene. Suggestions have gone back as far as the early Miocene (~20 m.y.a.) (McPhail in Stouder, et al, 1997; Montgomery, 2000)


His last rescue was on [[Whit Monday]] 1889, when he saved a young boy from the river. He died of tuberculosis the following year, at the age of 51, by which time he had rescued over 50 people from the river.<ref name="Nicholls2004P64" /> There is a large memorial to him in Weaste Cemetry, [[Salford]]. The Mark Addy Footbridge crosses the Irwell between Regent Road and [[Pomona Docks]], the Mark Addy Award (a swimming trophy) and an oil painting of him in [[Salford Museum and Art Gallery|Peel Art Gallery]] wearing his medals.<ref>Bracegirdle pp.&nbsp;133&ndash;136.</ref> There is also a [[public house]], named "The Mark Addy", built on the New Bailey Landing stage on the Salford side of the river near New Bailey Street.
[[Speciation]] among Oncorhynchus has been examined for decades, and to this day, a family "tree" is not completely developed for the Pacific salmonids. [[Mitochondrial]] DNA (mtDNA) research has been completed on a variety of Pacific trout and salmonid species, but the results do not necessarily agree with fossil research, or molecular research. It is generally agreed that [[chum]],[[pink]] and sockeye salmon lineages diverged in the sequence after other species (McPhail in Stouder, et al, 1997). Montgomery (2000) discusses the pattern of the fossil record as compared to [[tectonic]] shifts in the plates of the Pacific Northwest America. The (potential) [[divergence]] in Onchorhyncus lineages appear to follow the uprising of the Pacific Rim. The climatic and habitat changes which would follow such a geologic event are discussed, in the context of potential stressors leading to adaptation and [[speciation]] (Montgomery, 2000).


== Commerce ==
One interesting case involving speciation with salmon is that of the [[Kokanee]] sockeye. Sockeye that have been [[landlocked]] are called [[Kokanee]]. Kokanee sockeye evolve differently from anadromous sockeye. They reach the level of "biological species". Biological species - as opposed to morphological species - are defined by the capacity to maintain themselves in [[sympatry]] as independent [[Genetics|genetic]] entities. This definition can be vexing because it appears that it does apply only to sympatry, and this limitation makes the definition difficult to apply. There are examples in Washington ([http://www.livinglandscapes.bc.ca/thomp-ok/kokanee-salmon/view-life.html/ Kokanee Heritage Project]), [[Canada]] and elsewhere where two populations live in the same lake but spawn in different substrates, at different times, and eat different food sources. There is no pressure to compete or interbreed (two responses when resources are short). These types of Kokanee salmon show the principal attributes of a biological species: they are reproductively isolated, and show strong resources partitioning (McPhail in Stouder, et al, 1997).
[[Image:Barton Aqueduct.jpg|thumb|left| Barton Swing Aqueduct]]
=== Mersey and Irwell Navigation ===
In the late 17th century, the [[Warrington]] businessman Thomas Patten, had made the [[River Mersey]] navigable as far as Warrington and suggested that there would be significant commercial value in extending this along the Irwell as far as Manchester. In 1721, [[Parliament]] authorised the alteration with the "Mersey and Irwell Navigation Act", and by 1736 work had been completed by creating eight [[canal lock]]s along the {{convert|20|mi|km|0}} route from Warrington to Manchester, allowing access to boats of up to {{convert|50|LT|t ST|0|lk=on}}. The waterway played a central role in the [[cotton]] industry of the 18th century that spear-headed the [[Industrial Revolution]] and was known as the [[Mersey & Irwell Navigation]].


=== Bridgewater Canal ===
Today, the following Pacific Ocean species of [[salmon]] exist:
When [[James Brindley]] built the [[Bridgewater Canal]], the task of crossing the [[Irwell Valley]] was one of the main obstacles he faced. His solution was to build a canal-carrying bridge across the river, the world's first commercially driven [[aqueduct]]. The bridge consisted of three arches, and measured {{convert|12|m|ft|0}} high, {{convert|200|m|ft|0}} long and {{convert|11|m|ft|0}} wide. Upon its opening in 1761 it earned the nickname of "the Castle in the Air" and proved hugely successful in the industry of the area. The Mersey and Irwell Navigation and the Bridgewater Canal competed for trade to and from Manchester for the next 120 years and specially designed barges with a shallow [[draft (hull)|draft]], known as [[Mersey Flat| "Mersey flats"]], were used on both waterways. Over the years both trade and rivalry continued to grow with each company offering reduced freight charges or special rates and concessions to gain business from the other. The most important cargo carried was raw cotton from Liverpool to Manchester but timber, dyewoods, [[pig iron]], lead, copper, nails, tar, sand, grain and flour were also carried. Passenger services had been operating on the Bridgewater Canal for some years and in 1807 the Irwell and Mersey Navigation Company began to compete with daily services between [[Runcorn]] and [[Manchester]]. In 1816 they began to use packet steamers, however, in 1830 the [[Liverpool and Manchester Railway]] opened, [[packet boat]] services went into decline, and ceased to operate completely in the 1860s.<ref>[http://www.pittdixon.go-plus.net/m&i-nav/m&i-nav.htm History of the Mersey and Irwell Navigation]</ref> In Manchester two other canals used the Irwell as a point of access &ndash; the [[Manchester Bolton & Bury Canal]] from 1809, and the [[Manchester and Salford Junction Canal]] from 1839. Both are now non-navigable however the former is under restoration.


=== Manchester Ship Canal ===
'''Family Salmonidae (salmons, salmonids, and trouts)'''
As the 19th century progressed, the increasing need for large freight carriers led to [[Liverpool]]'s dominance as a port. Manchester became increasingly reliant on its [[Merseyside]] neighbour for its export industry but the handling charges and dues charged by the [[Mersey Docks and Harbour Board]] made goods from Manchester uncompetitive. A solution was to build the [[Manchester Ship Canal]].<ref>{{cite book
| last = Worthington
Genus Oncorhynchus (Pacific salmon)
| first = Barry
Species Oncorhynchus chrysogaster (Mexican golden trout)
| authorlink = Barry Worthington
Species Oncorhynchus clarkii (cutthroat trout)
| coauthors =
Species Oncorhynchus gilae (gila trout)
| title = Discovering Manchester: A walking guide to Manchester and Salford
Species Oncorhynchus gorbuscha (pink salmon)
| publisher = Sigma Leisure
Species Oncorhynchus keta (chum salmon)
| year = 2005
Species Oncorhynchus kisutch (coho salmon)
| location = [[Wilmslow]]
Species Oncorhynchus masou (cherry salmon)
| pages = 240
Species Oncorhynchus mykiss (rainbow trout/steelhead)
| url = http://www.sigmapress.co.uk
Species Oncorhynchus nerka (sockeye salmon)
| doi =
Species Oncorhynchus tshawytscha (chinook salmon)
| id =
Only Chinook, Coho, Sockeye, Pink, Chum, Steelhead/rainbow, and Cutthroat occur in the Puget Sound area.
| isbn = 1-85058-774-4}}
</ref> In 1887 the Bridgewater Navigation Company was purchased by the Manchester Ship Canal Company with a cheque for £1,710,000, which was at the time the largest cheque ever written, and the building of the Manchester Ship Canal began.<ref>[http://www.canalarchive.org.uk/stories/pages.php?enum=TE126&pnum=5&maxp=5 Canal Archive:Bridging the years]</ref>
The Ship Canal, which was made by expanding the route of the Mersey and Irwell Navigation, opened in 1894. Although it came too late to save the cotton industry that had made the region the centre of the Industrial Revolution, the canal transformed Manchester into England's third largest port, despite being {{convert|40|mi|km|0}} inland. As the canal was built, it became clear that Brindley's famous aqueduct would have to be demolished, as it allowed insufficient headroom for the freighters that the canal would carry. Fortunately, in 1896 the councillors of Eccles paid to have the aqueduct moved to the spot it occupies today, alongside the canal. The [[Bridgewater Canal]] is now carried over the Irwell/Ship Canal by the equally celebrated [[Barton Swing Aqueduct]], which was completed in 1893 with the novel idea of "opening" by rotating 90&nbsp;degrees to allow ships to pass.
[[Image:Waterside Walkway Oliver Dixon.jpg|thumb|right| Ontario Basin [[Salford Quays]]]]
The construction of the [[Manchester Ship Canal]] and the [[Salford Docks]] led to the development of [[Trafford Park]] as a centre of heavy industry and brought employment to the area for the next eighty years. However, by the 1960s the UK began to lose its position as an industrial world power. The decline of the heavy industries in the area, the increasing size of freight carrying ships and competition from road transport, brought about the decline of [[Salford Docks]] and they eventually closed in 1982. A large urban regeneration project, The [[Salford Quays]] Development Plan, was published in 1985 and work began a few years later to redevelop the site for residential, business and leisure purposes. The Salford Quays waterside development has made living by the Irwell, and the Manchester Ship Canal into which it flows, fashionable once again.<ref>{{cite web| last = Burdett | first = Jill| | title =Spotlight on Salford Quays | work =Home Search| publisher = Manchester Evening News | date = 2004-06-30 | url = http://www.manchesteronline.co.uk/homesearch/latest/whereyoulive/s/122/122679_spotlight_on_salford_quays.html | format = http| accessdate = 2008-02-18}}</ref>


There are further plans to "turn the tide on the years of neglect and once again embrace the River Irwell as a fundamental part of Manchester and Salford's heritage and future economic and social growth. The vision is to reinvent the central Manchester conurbation as the major waterfront destination in Northern England." A number of key stakeholders are involved in the development of this regeneration vision. These include Manchester, Salford and Trafford councils, Manchester Ship Canal Company, Environment Agency, Mersey Basin Campaign, local businesses, landowners, community groups and the wider Manchester, Salford and Trafford
==Degradation of Nearshore habitat in the Puget Sound==
communities.<ref>[http://www.merseybasin.org.uk/page.asp?page=1&pagesize=5&confirmed=1&id=2837&docid=190 Urban River Regeneration in Manchester: Transforming the "Dark River" Irwell]</ref>
"Nearshore" is most commonly defined as the backshore, [[intertidal]] and shallow [[subtidal]] areas of [[shoreline]]. In [[Washington]] for example, the [http://www.ecy.wa.gov/programs/sea/sma/ Shoreline Management Act] defines the upland edge of this area to be {{convert|200|ft|m}} behind the shoreline. Many groups also consider the nearshore to go fairly deep beyond the intertidal zone.


== Sport on the Irwell ==
While [[Puget Sound]] has enjoyed tremendous growth, the nearshore [[Natural environment|environment]] has declined. This environment is considered the "key to life in the Puget Sound [[estuary]]" ([http://www.ecy.wa.gov/pubs/0506018.pdf/ Washington State's Coastal and Estuarine Land Conservation Plan, 2005]). More than 10,000 [[streams]] and [[rivers]] drain into Puget Sound. Approximately {{convert|1800|mi|km}} of shoreline surround the estuary, which is a mosaic of beaches, bluffs, deltas, mudflats, and [[wetlands]] (Washington State's Coastal and Estuarine Land Conservation Plan, 2005). A number of factors have been listed as potentially contributing to continued degradation of the nearshore environment. These include changing the nearshore by adding artificial structures (tide gates, bulkheads), increased pollution from various sources such as failing [[septic]] systems, and various impacts from agricultural and industrial activities (Puget Sound Nearshore Project, 2006). One-third of more than 4,000 kilometers of Puget Sound shoreline has been modified by some form of human development, including armoring, [[dredging]], filling, and construction of overwater structures ([http://www.pugetsoundnearshore.org/documents/Principles.pdf/ Puget Sound Nearshore Partnership, Guiding Restoration Principles, 2006]).


There has been rowing on the Irwell in Manchester and Salford since 1823. A regatta was inaugurated on [[12 September]] [[1842]], on a straight course from Throstle's Nest Weir to Regent Road Bridge. Racing continued in Manchester with events such as Agecroft Regatta and Warburton Regatta. At the turn of the century, rowing was very popular in the area with many local clubs such as Nemesis, Prince of Wales, Minerva, Didsbury and Agecroft all competing regularly. However, the state of the river declined, and by the Second World War only Agecroft and Broughton rowing clubs were still active.<ref>{{cite web| last =Anon |title =Rowing in Manchester:History|work =Two Cities Boatrace|url =http://www.twocitiesboatrace.co.uk/History.html| format =http| accessdate =2008-04-25}}</ref>
A variety of species rely upon the nearshore environment, such as salmonids. Specifically, recent research has shown that juvenile salmonids rely upon the entire marine nearshore environment, not just upon localized areas, as some had previously thought ([King County, 2004/ http://dnr.metrokc.gov/wlr/watersheds/puget/nearshore/juvenile-salmonid-report.htm]). The research concluded that juvenile [[salmon]] use a diverse array of nearshore habitat types that have been significantly altered by human development activities. It connected salmon and both land and aquatic environments, which serve to support salmon and other species in the nearshore. For example, the report affirmed that juvenile chinook depend on food from both [[Marine (ocean)|marine]] riparian [[vegetation]] on land and shallow water habitats such as [[eelgrass]].


[[Agecroft Rowing Club]] was formed in 1861, making it one of the oldest open membership rowing clubs in the world.<ref>{{cite web| last =Anon | title =Agecroft Rowing Club |url=http://www.agecroftrc.org.uk/| format =http| accessdate = 2008-04-24}}</ref> The club originally held regattas and participated in rowing events but was primarily a social club for rowing enthusiasts<ref>{{cite web| last=Anon |title =Papers of the Agecroft Rowing Club |url=http://rylibweb.web.its.manchester.ac.uk/specialcollections/collections/guide/atoz/agecroft/index. |publisher=John Rylands University Library |accessdate=2008-04-21}}</ref> and was based near to [[Agecroft Hall]]. It now operates from a boathouse next to the Salford Watersports Centre at [[Salford Quays]] which it shares with the [[University of Salford]] Boat Club. The boathouse also hosts the [[Northern Universities Association|Northern Universities]] Boat Race, which was held on the river from 1972, but moved to the Quays in the early 1990s.<ref>{{cite web |last=Anon |title=Quays to Success |work =Campus Report |publisher=University of Salford|year=2004 |url=http://www.campus.salford.ac.uk/images/report/report_summer2004.pdf |format=[[PDF]] |accessdate=2008-04-25}}</ref>
The research had other interesting findings to share, including:


== Irwell Sculpture Trail ==
(1) Juvenile [[chinook]] were found for extended periods of time in the nearshore and often used the shallow shoreline areas of Puget Sound;
(2) Juvenile chinook stocks are broadly distributed and intermix in central Puget Sound;
(3) [[Hatchery]] chinook are more abundant than wild chinook in the nearshore environment;
(4) Juvenile chinook have diverse diets that are a product of the diverse habitats which make up the nearshore [[ecosystem]];
(5) Chinook appear to feed opportunistically on whatever prety are seasonally available, and change their diet from insects, marine [[plankton]], and epibenthic organisms to a diet of fish at approximately 130-150 mm in size;
(6) Juvenile chinook depend upon food from both marine riparian vegetation on land, and shallow water habitats, such as eelgrass, and
(7) Hatchery and wild chinook significantly overlap in space, time, and diet in the marine nearshore.


The [[Irwell Sculpture Trail]] is one of the largest public art initiatives and the longest sculpture trail in the UK.<ref>{{cite web| last =Anon |title =Irwell Sculpture Trail| work =Lancashire County Council website| publisher =Lancashire County Council | year = 2008 | url =http://www.lancashire.gov.uk/corporate/web/view.asp?siteid=2856&pageid=4961&e=e | format =http | doi = | accessdate = 2008-05-17}}
A variety of efforts are underway to improve the nearshore environment. These efforts work to improve education, planning, and adapative management, particularly with respect to local [[planning]] processes. Some of these efforts are:
</ref> The trail consists of a scenically varied, {{convert|30|mi|km|sing=on}} walking route based on the well-established Irwell Valley Way, stretching from Salford Quays to the moors above Bacup. Since 1987 over 30 pieces of public art have been commissioned from regional, national and international artists.<ref>{{cite web |last =Morland | first = Joanna| | title =Case Study: Irwell Sculpture Trail
| work =Public art online| publisher =Public Art Southwest| year = 2000 | url =http://www.publicartonline.org.uk/archive/casestudies/irwell_sculpture/trail.php| format =http| accessdate = 2008-05-17}}
</ref>


== Flood defences ==
[http://www.pugetsoundnearshore.org/whatwedo.html/ The Puget Sound Nearshore Partnership]
The lower reaches of the Irwell have flooded many times in its history, the most well documented being the floods of 1866, 1946, 1954, 1980, and 2007. Two flood storage basins with a capacity of {{convert|650000|m3|cuyd}} have been constructed to the west of Littleton Road, [[Kersal]], at a cost of around £11 million, to alleviate the flood problem and protect some 3,000 properties in Kersal and Lower Broughton against a 1 in 75 year flood, as part of the River Irwell Flood Defence Scheme.<ref>{{cite web| last = Anon | title =Current flood risks and management | work =River Irwell Catchment Flood Management Plan 2006| publisher = Environment Agency | date = 2004-06-30 |url= http://www.environment-agency.gov.uk/commondata/acrobat/irwell_03_1771695.pdf| accessdate=2007-12-11|month=December | year=2006|format=PDF}}</ref> However, it is said that a 1 in a 100 year flood would breach these defences and cause some £55&nbsp;million damage to property.<ref>{{cite web|url= http://www.mangeogsoc.org.uk/egm/5_1.pdf|accessdate=2007-12-11|date=2003-08-21|format=pdf|title= Exploring Greater Manchester&nbsp;— a fieldwork guide: The fluvioglacial gravel ridges of Salford and flooding on the River Irwell|author= Hindle, P.(1998)|publisher=Manchester Geographical Society}} p.10 </ref> The defences proved successful on [[2008-01-22]], when the worst flooding to hit the region in thirty years caused the Irwell to burst its banks further downstream in the centre of Manchester.<ref>{{cite web| last = Osuh | first=Chris| title =Floods clean-up under way
| work =Manchester Evening News| publisher = M.E.N. Media | year = 2006 |url= http://www.manchestereveningnews.co.uk/news/s/1033120_floods_cleanup_under_way|format=http| accessdate=2008-01-26|date=2008-01-22}}
</ref>


== Tributaries ==
[http://www2.wadnr.gov/nearshore/ The Washington State Department of Natural Resources, Nearshore Program]


Moving upstream from the Mersey Confluence, the tributaries include the following: -
[http://www.psat.wa.gov/Publications/biennialplan/05_07_PSplan.htm/ Washington State's Puget Sound Conservation and Recovery Plan]
[[Image:Roch Irwell confluence Keith Williamson.jpg|thumb|right|Confluence of the Roch and Irwell at [[Bury]]]]
[[Image:Irwell at Cromwell Bridge.jpg|thumb|right|The Irwell at Cromwell Bridge, [[Broughton, Greater Manchester| Broughton]]]]
*Platts Brook
*Bent Lanes Brook
*Salteye Brook
**Worsley Brook
*[[River Medlock]]
*[[River Irk]]
*[[River Croal]]
**[[River Tonge]]
***[[Bradshaw Brook]]
***[[Astley Brook]]
***[[Eagley Brook]]
*[[River Roch]]
**[[River Spodden]]
**[[River Beal]]
*Pig Lees Brook
*Kirklees Brook
*Dearden Brook
*[[River Ogden]]
*Whitewell Brook
*Limey Water


== References ==
[http://www.ecy.wa.gov/pubs/0506018.pdf/ Washington State's Coastal and Estuarine Land Conservation Plan, 2005]
=== Notes ===
{{reflist|2}}


=== Bibliography ===
==The Needs of Salmonid Species for Survival==
{{commonscat|River Irwell}}
Salmon are the primary nearshore species most think of in [[Puget Sound]]. In order for [[salmon]] to revive in the Puget Sound, their basic needs must be met. According to David Montgomery (King of Fish, 2003), these needs include cool, unpolluted [[water]]. Under the Federal Endangered Species Act, the Puget Sound has been designated a [http://www.nwr.noaa.gov/Salmon-Recovery-Planning/Recovery-Domains/Puget-Sound/Index.cfm/ [[recovery]] domain] for purposes of helping threatened and [[endangered]] salmon to survive. Within this domain, three Evolutionarily Significant Units (ESU) of salmon species have been designated: Lake Ozette Sockeye, Hood Canal Summer [[Chum]] and Puget Sound [[Chinook]] ([http://www.nwr.noaa.gov/Salmon-Recovery-Planning/Recovery-Domains/Puget-Sound/Index.cfm/ National Marine Fisheries Service]). [[Bull trout]] has also recently been listed by the United States Fish and Wildlife Service. Two populations are found in Washington, and one is located in Puget Sound ([http://www.fws.gov/pacific/bulltrout/jcs/index.html Bull Trout Population Map for Washington]).
{{refbegin}}
*{{cite book |title=The Dark River |author=Bracegirdle, Cyril |coauthors=Illustrated by Ernest Wallace Brereton |year=1973 | publisher=Sherratt |location=Altrincham |isbn=0-85427-033-7}}
*{{cite book |first=Robert |last=Nicholls |title=Curiosities of Greater Manchester |publisher=Sutton Publishing |year=2004 |isbn=0750936614}}
*{{cite book| last =Brereton| first =Wallace| title =Irwell Gallery| publisher =Salford Local History Society| year =1978| location =Salford}}
{{refend}}


== External links ==
In general, most salmon require clean [[gravel]] streambeds to lay their eggs, a [[flood]] regime in tune with their life cycle, accessible habitat that provides food and cover from predators, and functionally diverse streambeds. These biological requirements are increasingly impacted inside and outside of Puget Sound. NOAA Fisheries lists the primary factors influencing the survival of salmon as being:
* [http://www.pittdixon.go-plus.net/m&i-nav/m&i-nav.htm History of the Mersey and Irwell Navigation (Old Quay Company)]
* [http://www.salfordadvertiser.co.uk/news/s/1033073_worst_flooding_in_decades Salford Advertiser 21 January 2008: Worst flooding in decades]
* [http://environment.info/commondata/acrobat/section_3_1097346.pdf Irwell Catchment Flood Management Plan:Current flood risks and flood risk management]
* [http://www.penninewaterways.co.uk/manchester/salfordquays.htm Salford Quays virtual tour]
* [http://www.canalarchive.org.uk/stories/pages.php?enum=TE126&pnum=1&maxp=5 Mersey and Irwell Navigation with images]
* [http://www.penninewaterways.co.uk/manchester/m70.htm Photos of the Mersey and Irwell Navigation]


== Gallery ==
#Water storage, withdrawal, conveyance and diversion
#Natural resource use and extraction leading to habitat modification
#Loss of connectivity and complexity between and within watersheds
#Impacts of recreational, commercial and illegal fishing
#Introduction of non-native species and modification of habitat resulting in increased predator populations
#Natural environmental conditions (drought)
#Hatcheries ([http://www.nmfs.noaa.gov/pr/species/fish/salmon.htm/ NOAA Fisheries, Office of Protected Resources])


<gallery>
Montgomery (2003) has reported that woody debris, such as logjams in Puget Sound [[rivers]] and [[streams]] provide important wintering habitat for juvenile [[salmon]]. Logjams protect the salmon from predators and tumultuous waters. In 1880 the [[US Army Corps of Engineers]] began a process of "desnagging" Northwest rivers, one of the first actions by settlers harmful to [[salmon]] populations (Montgomery 2003). There is currently a movement among environmentalists to create engineered logjams (ELJs) to restore [[salmon]] habitat in the Puget Sound area.
Image:Irwell Source .jpg|The source of the Irwell at Deerplay Mooor
Image:Burrs Country Park.jpg|Burrs mill at [[Summerseat]], originally had a water wheel powered by the river
Image:Burrs Weir Summerseat.jpg| Burrs Weir, constructed around 1800 to divert the water via a small feeder canal to the mills
Image:River Irwell, Rawtenstall.jpg|Downstream from New Hall Hey, [[Rawtenstall]]
Image:Irwell and Mersey Confluence.jpg|Confluence with the River Mersey


</gallery>
The salmon are an [[icon]] of the Puget Sound, and ensuring their survival has become important to many agencies, groups, and interested citizens. These stakeholders consider salmon a fundamental icon of residency in Puget Sound. "Besides humans, no other creature penetrates the Northwest so completely. The salmon is to the entire Northwest what the spotted owl was to old-growth forests--a telling indicator of ecological health" (Mindy Cameron, The Seattle Times, [[August 18]], [[2002]], p. D1).


{{Greater Manchester}}
The abundunce of salmon is something that can be seen, touched, and even tasted. Many take extreme pride in working towards the recovery of salmonids, and although they see it as a huge task to be fulfilled, they consider their duty to an icon of [[Washington|Washington State]]. All the pride in the Puget Sound will make it so worthwhile.


{{DEFAULTSORT:Irwell}}
==The Role of Hatcheries and Salmon Recovery==
[[Category:Rivers of Great Britain]]
[[Category:Rivers of England]]
[[Category:Rivers of Lancashire]]
[[Category:Rivers of Greater Manchester]]
[[Category:Rivers of Bolton]]
[[Category:Rivers of Bury]]
[[Category:Rivers of Manchester]]
[[Category:Rivers of Oldham]]
[[Category:Rivers of Salford]]


[[no:Irwell]]
[[Hatcheries]] have produced Pacific salmon for nearly 130 years. The first hatchery was located on the Baker River, built in 1896. Over this time, hatcheries have provided valuable data on salmon [[ecology]] and behavior by providing capture and release rates - the number of salmon that were captured returning as adults to spawn, compared to those that were originally released as smolts. We can extrapolate from this how salmon adapt to changing [[freshwater]] and [[Marine (ocean)|marine]] conditions, alteration in habitat, and natural disasters, such as wildfire and drought.

More than 100 hatcheries are operated in Puget Sound and coastal Washington by the Washington State Department of Fish and Wildlife (WDFW), Puget Sound and coastal Indian Tribes, and the U.S. Fish and Wildlife Service (USFWS). Most were built to produce fish for harvest in response to declines in naturally spawning salmon populations (Washington State Department of Fish and Wildlife, 2006).

Hatcheries now provide 70 percent of the salmon caught in Puget Sound and are the linchpin of an $854 million annual [[recreational]] [[fishing]] economy in Washington State (ranked eighth in the nation). Hatcheries also play an important role in meeting [[tribe|Tribal]] [[treaty]] harvest obligations. As better scientific information has become available, however, hatcheries have been identified as one of the factors responsible for the decline of naturally spawning populations. It has been difficult to conclusively prove negative impacts on naturally spawning salmon by hatchery fish and this is a subject of debate among fishery scientists.

One set of data that helped determine how the management of hatchery salmon impact wild salmon came directly from the federal government. A Caucus of nine federal agencies convened to study on a basin-wide scale the salmon decline in Washington state. In the year 2000, the Federal Caucus published a report concluding that (1) the decline of salmon was well-documented, and (2) there were four human activities linked to this decline: changes in [[Habitat (ecology)|habitat]], the use of [[hydropower]], [[harvesting]], and [[hatcheries]]. These actitivies became known as the "4 H's" ([http://www.salmonrecovery.gov/reports_and_papers/all_h_strategy/ Federal Caucus], 2000).
Modern hatchery practices seek to minimize any chance of adverse impact to naturally spawning fish. Some hatchery programs are specifically designed to assist in the restoration of weak and endangered populations.

The report recommended two strategies with respect hatcheries and the recovery of threatened and endangered salmon. First, reform was necessary for all production and mitigation hatcheries to reduce any harm to wild salmon. Second, supplemental and captive broodstock programs were recommended to act as "safety nets" while long term recovery goals were worked towards. It was highly recommended that hatcheries produce fish genetically diversified for the local environment into which they were released, and naturally capable of interbreeding with wildstock without any harm. To meet this goal, the Federal Caucus suggested that salmon hatcheries develop a Hatchery and Genetics Management Program (HGMP). Hatcheries would also start using eggs collected from native, wild salmon, rather than non-native salmon, for captive broodstock ([http://www.salmonrecovery.gov/reports_and_papers/all_h_strategy/ All H Strategy, Federal Caucus, 2000]).

At that time, state, Tribal, and federal managers of Washington's salmon and steelhead were working to find ways to ensure that their hatcheries did not present a risk to several Puget Sound and coastal stocks that were listed or proposed for listing as threatened under the federal Endangered Species Act (ESA). In Washington State, tribal and state hatchery managers wanted to go above and beyond complying with the baseline terms and conditions provided under the Federal ESA. It had become apparent that a statewide hatchery system had to be developed that would recover and conserve wild populations, while supporting a sustainable fishery. The collaborative project of Hatchery Reform began. This effort allowed science to direct management and policy.

This effort was started by a non-profit group called [http://www.lltk.org/aboutUs.html Long Live the Kings]who had been working for some time in a collaborative manner with local, state, tribal and federal entities on [http://www.lltk.org/hatcheryReform.html hatchery reform]. The result was the [http://www.lltk.org/HRP_About.html Puget Sound and Coastal Washington Hatchery Reform Project], approved by Congress in 2000. This project provided appropriated funds that would:

(1) Provide for an independent, scientific panel to oversee hatchery operations within the state of Washington ([http://www.lltk.org/HRP_HSRG.html Hatchery Scientific Review Group]); (2) Provide a competitive grant program for projects that addressed hatchery-related impacts; (3) Support state and Tribal efforts to implement hatchery reform, and (4) Provide for the facilitation of a reform strategy by an independent third party. In April 2004, the Hatchery Scientific Review Group produced the [http://www.lltk.org/HRP_Publications_HSRG_Recs.html first report] on changes that were required within hatchery management in order to assist in the recovery of salmon in Washington state (Long Live the Kings, 2006).

While the Hatchery Reform Project was being developed at the state level, decisions about the management of hatchery and endangered wild salmon were being made at the federal level. In 2001, a District Court had ruled that the federal government's strategy of grouping hatchery and wild salmon for purposes of defining "evolutionary significant units" (ESUs) but separating hatchery and wild salmon for purposes of defining threatened and endangered species was not legally valid. The government was ordered to find a different procedure. The resulting solution was to group both hatchery and salmon for both purposes of defining ESUs, '''and''' for purposes of determining whether the species is threatened or endangered under the Endangered Species Act.

This decision was controversial. A [http://compassonline.org/files/inline/HatcheriesPRFinal_0.pdf letter] appeared in the peer-reviewed journal Science, signed by the Salmon Science Recovery Review Panel, a National Research Council-approved group of six ecologists that had been requested to provide recommendations on Pacific salmon recovery to the National Marine Fisheries Service (NMFS). However, NMFS declined to use the group's recommendations, stating that the group went outside the realm of science and into policy. The group chose to publish their recommendations in the Journal ''Science''. The published article stated that hatchery fish should not be included with wild fish ([http://www.sciencemag.org/cgi/content/summary/303/5666/1980?siteid=sci&ijkey=wbYfIRiC4zYWV&keytype=ref Myers, R.A. et. al. 2004])

Soon afterwards, the National Oceanic and Atmospheric Administration (NOAA), the parent agency of NMFS, had their Fisheries Division release a [http://www.publicaffairs.noaa.gov/releases2004/may04/noaa04-r144.html formal statement] on their hatchery policy, expressing a desired commitment to ensure the survival and recovery of wild salmon, recognizing that some hatcheries promote recovery and some hatcheries do not. Since that time, a lawsuit has been launched against the federal government, calling this decision "arbitrary and capricious", citing the decision not to allow the Salmon Science Recovery Review Panel's recommendations - or the Panels' references and citations - as just one reason. The [http://www.tu.org/site/apps/nl/content2.asp?c=7dJEKTNuFmG&b=346309&ct=2159881 lawsuit] was allowed to proceed by a Seattle federal District Court judge, and is led by the non-profit advocacy group, [http://www.tu.org/site/pp.asp?c=7dJEKTNuFmG&b=275410 Trout Unlimited]. The local, state and Tribal-based Hatchery Reform effort proceeds forward, while federal efforts to address hatcheries and salmon recovery remain entangled in legal complexities.

==Salmon==
The Puget Sound estuary is home to many marine creatures including Orca whales, seals and Pacific salmon. Pacific salmon are an iconic species of the Puget Sound Region and spawn in most major tributaries that feed the sound. King or [[Chinook salmon]] are one of the many species of salmon in the Puget Sound, as well as [[Coho salmon|Coho]], [[Chum salmon|Chum]] and [[Sockeye salmon]] (Montgomery, 136).

The declining salmon population in [[Puget Sound]] is "a telling indicator of the ecological health" of the area and "billions of dollars have been spent to reverse the declining salmon runs" (Cameron 2002:D1). The declining salmon population in the Puget Sound can be attributed to several factors. Many of these factors include, however are not limited to: [[habitat (ecology)|habitat]], [[hydropower]], [[overfishing|overharvesting]], hatcheries, and "the Fifth H" history. Salmon have ecological requirements such as logjams, wood and gravel in the rivers, high oxygen content, correct ocean and fresh water temperature, and proper sunlight. History has the power to greatly impact the rise and/or fall of the salmon population in the Puget Sound. "Humans have conducted at least three full-scale experiments on how well salmon adapt to a changing landscape. Salmon failed each time, first in [[Great Britain]], then in [[New England]], and now in the [[Pacific Northwest]]" (Montgomery 2003:3).

Pacific Salmon have disappeared from 40 percent of their historic range outside Alaska. For every 50 salmon the Columbia River basin supported 150 years ago, today it is estimated to support seven. The state of Washington continually tried to place the blame for this decline on Native American fishing, even as commercial fisheries took more than a sustainable amount of fish each year. State courts continually curtailed Native American fishing rights by limiting the sites and times of year that they could fish (Montgomery, 2003). When brought to the federal courts, however, these cases have been repeatedly overturned, as in the landmark [[Boldt Decision]] of 1974. In this decision, Judge Boldt consulted the original treaties made with numerous tribes in the 1850s to determine what rights the Native Americans had regarding fishing. The treaties all stated that the tribes had the right to fish at “all usual and accustomed places" and that this right was "secured to said Indians in common with all citizens of the territory” (Document: Boldt Decision). Judge Boldt interpreted the phrase “in common” to mean that the Native Americans and other citizens were each entitled to half of the fish harvest. This was a groundbreaking decision whose repercussions are still being felt today, especially by fishermen who complain that the Native Americans take nowhere near the half allotted to them.

There has been a struggle on [[salmon]] returning to their Pacific Northwest rivers and streams because of the struggling northwests economy. This provides a much-needed economic influx from increased recreational and commercial of salmon fishing. Three percent of wild salmon runs in the [[Columbia Basin]] are below historic numbers. Recent studies also show that the oceans temperature may be warming again and that the Northwest is suffering its sixth straight year of below-average waters. [http://www.wildsalmon.org/library/returns.cfm/ Save Wild Salmon]

Under provisions of the federal Endangered Species act, numerous salmon populations throughout the Pacific Northwest have been listed as endangered (Cameron 2002: D1).
One of the factors that contribute to declining [[salmon]] runs in [[Puget Sound]] and the [[Pacific Northwest]] in general, is the lack of logjams in rivers. As stated above, logjams are essential to the survival of healthy salmon populations. Logjam and river current interaction carve deep pools into riverbeds, providing salmon and their young, also known as [[fry]], with hiding places from predators. Logjams also force some of the water from the main river to spill out over the adjacent [[floodplain]], forming [[tributaries]] along the river which supply ideal habitat for maturing salmon. The natural processes of [[spawn (biology)|spawning]] and reaching maturity become much more difficult for salmon without the services logjams provide (Montgomery 2003).

Another reason for salmon population decline is the use of increasingly sophisticated fishing technology. Some of the first Native American fishermen depended only on canoes, nets made from nettle or cedar fiber, and their personal skill to catch fish (Pacific Coast 2005). Today’s fishermen use trackers to locate the fish they want to catch, whether salmon or otherwise, and then use technology like powerboats, winches, and nets made of almost unbreakable substances to catch the desired species. Advances in technology have their disadvantages, however. Advances in fishing technology have enabled fishermen to catch more and more fish of all sizes and species. For an extended period of time now, fishermen have been catching not only the larger, mature fish, but also the smaller, immature fish that have not had the chance to reproduce. This practice is detrimental to salmon populations because it does not leave any fish to propagate the salmon species.

In addition to technological advancements in fishing, invasive species and natural predators threaten the remaining salmon population. These include, but are not limited to, harbor seals, sea lions, killer whales and various sea birds. While these species are natural predators of salmon, juvenile salmon also have competition to deal with when gathering food. One major source of competition are jelly fish who feed on the same organisms as juvenile salmon. The proliferation of jelly fish and decrease of salmon could potentially lead to the "infestation" of jelly fish in local waters. [http://www.shiftingbaselines.org/ Shifting Baselines] Also, as the organisms which salmon feed on begin to dwindle due to factors including overfishing and invasive species, salmon are further threatened as their food sources become precarious, as is the case with herring populations around Puget Sound (Puget Sound Action Team).

===Habitat===
The Puget Sound boasts an impressive habitat for Salmon, as well as other flora and fauna necessary for the species’ survival. Healthy eelgrass and kelp beds foster juvenile salmon as they make the change from small rivers and streams to a new ocean habitat in the Puget Sound before they travel onto the Pacific Ocean. Prey for salmon at different stages of their lives also thrives in healthy Puget Sound habitat including sand lances and rockfish (Klinger, 2005). As it applies to habitat, the human population along the Puget Sound shoreline has made these pristine environments harder and harder to come by. Shorelines have been bulk-headed and armored, estuaries have been filled to make agricultural land and naturally occurring log jams have been removed to make navigation in the Sound easier (Montgomery, 2003). Habitat degradation is cited by the Washington Department of Fish and Wildlife as one of the major contributors in reducing the Salmon stock’s resilience (Washington Department of Fish and Wildlife, 2001). An additional loss to salmon habitat along the Puget Sound has been that of salt marsh habitats along shorelines. These habitats provide salmon with important grounds for shelter as well as food. Nearly all salt marshes in and around the major urban areas around the sound have been destroyed - in fact there has been a 73% loss of salt marsh habitat in and around the Puget Sound altogether over the last 125 years. [http://www.ecy.wa.gov/programs/sea/pugetsound/species/salmon.html/ Washington State Dept. of Ecology]

===Hydroelectric Dams===
Hydroelectric dams contributed to the decrease in salmon populations as well. They prevent adult salmon from entering upstream to spawn. The fluctuation in water flow put tremendous amounts of stress on salmon and reduces their ability to survive (Montgomery 2003). Some dams have fish ladders that allow salmon to pass through the dam. This system does help salmon to reach their spawning sites, however, the juveniles often get killed on the way downstream by the turbines in the dam. There are huge controversies about whether to actually stop the dams or to let it run. Discontinuing the dams would not provide enough energy for us, since about 55% of our energy is provided by hydroelectric dams. On the other hand, environmentalists are in favor of stopping hydroelectric dam operations. [http://www.nwd.usace.army.mil/ps/colrvbsn.htm/ Columbia River Basin]

Dams affect almost all the major rivers in the Pacific Northwest region, particularly near the Puget Sound. Some important river systems for salmon affected by hyrdroelectric dams include the [[Baker River (Washington)]], [[Nisqually River]] and [[Green River (Washington)]] systems. As mentioned before dams impede the natural lifecycle of salmon by creating physical barriers to their spawning grounds with detrimental consequences. Reduced water velocity from these barriers significantly increases the time needed for young salmon to travel down the river to start the ocean phase of their lifecycle. This augmentation in migration time for salmon and alteration in "timing" possibly leads to disorientation and an increased susceptibility to predation. [http://www.fwee.org/hpar.html/ Foundation for Water and Energy Education] Another adverse effect known as "supersaturation" can occur as well for fish encountering dams that is similar in nature to the "bends" that can kill humans. Dams also play a major role in "taming" once "wild" rivers, the latter much more beneficial to sustaining wild salmon populations, thus negatively altering the natural environmental dynamics of ecosystems suitable for salmon. (Montgomery 2003, p. 239).

===Over Fishing===
Over fishing is another major historic factor in the depletion of [[salmon]]. Salmon became popular because it was considered very cheap compared to the growing costs of meat. As fishing became more and more popular so did [[canneries]]. In 1877 the first [[Puget Sound]] cannery was built in Mukilteo and by 1900 Puget Sound had expanded it’s operating canneries to 19. The effectiveness of the cannery fish traps were so great that biologists began to argue that a guaranteed number of fishes needed to be allowed to escape the nets to reach their spawning grounds in order to prevent the total extermination of salmon (Montgomery 137). The production of canned salmon grew slowly until about 1890 when it really started to pick up rapidly. As the great [[World Wars]] of the 1900’s started to take place canneries started to decline progressively. This was mainly due to voters supporting salmon protection initiatives because of their traps were banned in the state of Washington as voters passed Initiative 77. However because of this Oregon fishing boats began increasing their catch since Washington banned their traps. Through this there was no increase in the number of salmon reaching their spawning grounds 18 years after the initiative passed. The ban in Washington eventually led to technological advances in salmon fishing. Vessels for open-ocean salmon fishing started developing in the 1930’s through advances in marine technology. This allowed huge floating canneries to harvest and package salmon in the open ocean far from where runs were originally from. Thus, through the development of marine technology countries with no salmon or depleted runs could harvest fish in other country’s open water which in turn began to mess with salmon conservation and recovery efforts (Montgomery 139). Now, [[Alaska]] currently hosts most of the American salmon fisheries because they are able to maintain relatively healthy habitats and salmon runs (Montgomery 143). Alaskan and Canadian fisheries do have impacts on Puget Sound salmon stocks.

Currently, fisheries are managed to minimize impacts on weak and endangered stocks of fish. Nearshore and freshwater fisheries are regulated by the Washington Department of Fish and Wildlife and the treaty Indian tribes. Ocean fisheries off the coast of Washington are managed through the Pacific Fishery Management Council and Pacific Salmon Commission processes. Fisheries impacting endangered species are required to have permits under the Endangered Species Act.

==Invasive Species==
Aquatic nuisance species are non-native plants or animals that threaten the diversity or abundance of native species, the ecological stability of infested waters, or the commercial, agricultural or recreational activities that depend on such waters (Chapter 77.60 RCW). In recent years, the Puget Sound has seen an increase of invasive species, specifically from Japan. M. McGrann, D. Sloan, and A.C. Cohen in their paper called, ''Invasion by a Japanese marine microorganism in Western North America'' from the March 2000 edition of '''''Hydrobioligia''''', state that a certain organism had invaded as early as 1971 in Puget Sound. In recent decades, society and how it relates to the ocean has become increasingly globalized. Invasive species have come to the Puget Sound via several factors, including aquaculture, importation of live seafood, shipping (attached to ship hulls and through ballast water), research and academic institutions, deliberate introductions, pet stores and public aquaria, and natural dispersal. [http://dnr.metrokc.gov/wlr/waterres/marine/exotic.htm/ Department of Natural Resources] The European green crab, Carcinus maenus, and the marine grass Spartina are currently two of the most damaging species. In respone to such trends, ocean species have migrated to places they shouldn't. Marjorie Wonham and James Carlton in their article entitled, ''Trends In Marine Biological Invasions at Local and Regional Scales'', published in 2005 in '''''Biological Invasions''''' declare the Puget Sound has the most introduced invasive species. Nationwide, about 400 of the 958 (42 percent) species listed as threatened or endangered under the Endangered Species Act are considered to be at risk primarily because of competition with and predation by non-indigenous species. [http://www.psat.wa.gov/Programs/Aquatic.htm/ Puget Sound Action Team]

The Washington Department of Fish and Wildlife is now attempting to combat its exotic species problem with the Washington State Aquatic Nuisance Species Management Plan. Under this plan, Washington State Patrol Commercial Vehicle Inspectors search incoming vessels for harmful invasive species, such as the zebra mussel, and decontaminate the vessels before they can spread the organism. [http://www.wdfw.wa.gov/fish/nuisxsum.htm/ Washington Fish and Wildlife] The plan also established an Aquatic Nuisance Species committee to find other ways to protect Washingtonians from the harm done by invasive species. The committee coordinates responses to threats at the federal, state, local and tribal as well as private levels, and presents a biennial report to the Governor's office to ensure that the situation is always under control.

==Pollution==

The population in the greater Seattle area has grown by over 18% from 1990 to 2000 (censusscope.org). This population will continue to grow and increasingly pollute Puget Sound. The strain on Puget Sound is augmented by the fact that it is still legal to discharge chemicals such as lead, PCBs, and mercury into Puget Sound waterways. These chemicals are dangerous not only to humans but to marine organisms as well, as the PCB's build up their systems. In fact, over 70 waterways in Washington State have unsafe levels of these and similar chemicals (pugetsound.org). Hydrocarbons result because of burning coal or petroleum. Many industries and steamships also use coal as a power source. In the early 1900s, pollution increased dramatically because of these hydrocarbons. By 1943, the pollution began to decline. In 1970, the level of hydrocarbons dropped to its original level of fifty years before. Puget Sound Environmental Issues In addition to the dangers posed discharging chemicals directly into Puget Sound, storm water runoff contributes significantly to the level of pollution. During rainy weather, the toxins on city streets will be swept away by the running water and will be delivered to storm drains. This toxic water is directly delivered to Puget Sound.

===Oil Spills===

Oil spills pose another major threat to the Puget Sound marine wildlife and ecosystems. Since 1989, there have been 225 oil spills in Puget Sound. Nearly everyday Puget Sound imports 550,000 barrels of unrefined oil each day. Thus making Puget Sound one of the country's primary centers for refining petroleum. ([http://www.psat.wa.gov/ Puget Sound Action Team]) One such spill on October 14th, 2004 in Dalco Passage leaked nearly 1,000 gallons over Vashon and Murray Island. The effects of oil spills were wide spread affecting the Maury Island Aquatic Reserve which inhabits sensitive eel grass and forage fish spawning areas which are necessary for native salmon and orca populations. ([http://www.pugetsound.org/index/ People for Puget Sound])

223 of these spills have been deemed ‘serious,’ and have released a combined 114, 405 gallons of oil in the Sound. Two of the 225 spills have been called ‘major,’ and include the Exxon Valdez spill in 1989 and another in 1999 off the coast of Bellingham, Washington. [http://www.psat.wa.gov/Publications/StateSound2004/State_Sound_Water_toxic7.htm Puget Sound Online] Because more than 600 vessels travel through Puget Sound every day, many believe that a disastrous oil spill is imminent. [http://www.pugetsound.org/index/spills People for Puget Sound] An oil spill even bigger than the Exxon Valdez incident could devastate the precious Puget Sound environment. Toxins could infiltrate every aspect of the Sound, including all marine and plant life.

===Population===

Times have changed since the 1970’s when a billboard in Seattle read “the last person to leave Seattle please turn out the lights” (Montgomery 2003: 8). The expansion of Microsoft and Boeing has spurred on an economic growth in the area. The 12-county Puget Sound region including Seattle and Tacoma, has quadrupled to 4 million people since the 1950’s and the state predicts 1 million more residents by 2025 (Pugetsound.org). This has major environmental implications including pollution runoff and the altering of important shorelines. “One-third of Puget Sound shoreline has already been altered” (Klinger, 2005). Population can also indirectly cause problems for fragile marine environments; for instance, the gravel mining operation at [[Maury Island]], started in part to provide materiel for the proposed third runway at Seattle-Tacoma International Airport as well as to repair overused roads in the area, carries with it a host of aquatic environmental implications.

==Coastal Development==

Another factor contributing to the salmon decline in the Puget Sound region is coastal development. The concrete walls that are often used to protect coastal housing from large surf are also contributing to the destruction of coastal habitat. These concrete walls can often destroy the gravely beaches that are essential parts of salmon habitats. These walls can also affect eelgrass beds that are located just off shore. Salmon and many other fish rely heavily on eelgrass beds for food and protection. These concrete walls are known as bulk-heads, and from 1977 to 1992 in Thurston County, shoreline amoring (which includes bulkheads) doubled - right where the Deschutes River dumps into the Puget Sound. [http://www.sharedsalmonstrategy.org/watersheds/watershed-southsound.htm/ Shared Salmon Strategy]. These bulkheads also alter [[shore drift]], riding beaches of important sediments, shelter, and food for salmon. Shoreline vegetation and feeder species are also often lost due to bulkheads. [http://www.ecy.wa.gov/programs/sea/pugetsound/species/salmon.html/ Wa. State Dept. of Ecology - Salmon]. There are very few remaining undeveloped coastal beaches in the Puget Sound; however one of the few remaining "pristine" undeveloped beaches those along the shores of [[Maury Island]]. These beaches are almost as close as you can get to pristine, and that is because they have been carefully zoned to protect the coastal waters. If we want to keep the remaining salmon habitat we need to conserve and protect the remaining semi-pristine coastline.

==Solutions==

Although Puget Sound and its inhabitants all must face difficult issues, there are many significant forces working hard to counteract the degradation of the region. In regards to salmon, the National Research Council recommended a publicly-accountable scientific advisory board to help direct conservation efforts on a larger scale (National Research Council, 1996). Many grassroots organizations, ie. People for Puget Sound, have developed into powerful centers for lobbyists and have created and enacted programs to monitor, restore or preserve the environment [http://www.pugetsound.org/index/ People for Puget Sound].
In addition, the state government has expressed its concern for the region, creating groups like "Puget Sound Action Team" to restore and maintain the health of the sound. [http://www.psat.wa.gov/]. This organization, like many others currently has programs to remove fishing gear, increase salmon population and health, and improve nearshore habitat. With the support of local communities and state sponsorship, organizations are able to help provide restoration and protection regarding a wide range of issues in the region.
The Washington State government has also adapted the federal government's "[[marine protected area]]" or MPA system into designated Aquatic Reserves, defined as "aquatic lands of special educational or scientific interest, or lands of special environmental importance that are threatened by degradation" (WAC 332-30-151). Like its national MPA counterpart, Aquatic Reserves are meant to serve as aquatic versions of national parks or sanctuaries. [http://mpa.gov/what_is_an_mpa/definition.html] Through the Aquatic Reserve Program, the Washington State Department of Natural Resources hopes to control these areas in an effort to restore, preserve, or enhance habitats and species that directly tie in to the aquatic ecosystem. The first Aquatic Reserve created under the new program was at [[Maury Island]] in November of 2004 (see also: [[South Maury Island environmental issues]]). Further candidate sites now under review include Cherry Point, Fidalgo Bay, Cypress Islands, and Orca Pass. [http://www.dnr.wa.gov/htdocs/aqr/reserves/home.html#sites]

===Solutions for Puget Sound Salmon Protection===

Federal involvement is also crucial to the long term survival of salmon. The majority of the decline in salmon population is attributable to the effects of population growth within the region, such as damming of Puget Sound tributaries and pollution of Puget Sound. However, some proposed solutions have little to do with directly addressing the effects of population growth. Federally sponsored actions have been proposed in defense of salmon including the poaching of seals and sea lions (which are also federally protected species) in waterways (such as the Puget Sound) where the salmon runs are depleted and the seals and sea lions are threatening the survival of the salmon (Earth Island Journal, 1998). Another commonly proposed solution is the increased implementation of salmon hatchery programs. Proponents of the plan argue that hatcheries are essential to the survival of salmon within the Puget Sound region and beyond. Other groups argue against the hatcheries because they claim that it offsets the environmental balance by introducing the artificially raised salmon populations and pitting them against the natural population. There are debates over the effectiveness of hatcheries and a summation is presented by E.L. Brannon in “The Controversy about salmon hatcheries.” (Brannon, 2004).

==References==
{{Reflist}}
*Brannon, E.L. (September 2004). “The controversy about salmon hatcheries.” FISHERIES 29 (9): 12-31.

*Cameron, Mindy. Seattle Times. [[18 August]] [[2002]]. pg:D1

*Christie, Patrick, Assistant Professor, Society and the Oceans Lecture, The University of Washington, April 2005.

*Earth Island Journal. (Summer 1998). v13 n3 p8(1).

*Emerick, Christina M. Introduction to the oceans. Kendall/Hunt Publishing Company 1991. Page: 39

*Federal Caucus, 2004. Conservation of Columbia Basin Fish: Final Basinwide Salmon Recovery Strategy. December 2000. Available online: http://www.salmonrecovery.gov/reports_and_papers/all_h_strategy/ Accessed [[August 9]], [[2006]].

*Hatchery Scientific Review Group, 2004. Scientific Framework for the Artificial Propagation of Salmon and Steelhead. April 2004. Available at: http://www.lltk.org/pdf/HSRG_Scientific_Framework.pdf Accessed [[August 9]], [[2006]].

*Keith A. Sverdrup, Alyn C. Duxbury, and Alison B. Duxbury. An Introduction to the World’s Oceans. McGraw-Hill. 2003. Pages: 328, 337-339

*King County, Natural Resources and Parks: Water and Lands Division. 2005. Juvenile Salmonid, Composition, Timing, Distribution and Diet in Marine Nearshore Waters of Central Puget Sound, 2001-2002. Available at: http://dnr.metrokc.gov/wlr/watersheds/puget/nearshore/juvenile-salmonid-report.htm/ Accessed [[August 8]], [[2006]].

*Klinger, Terry, Assistant Professor, University of Washington, Lecture for Society and Oceans. 2005.

*Long Live the Kings, Hatchery Reform Science Group. Publications Website. 2006. http://www.lltk.org/HRP_Publications.html Accessed [[August 9]], [[2006]].

*McPhail, J.D. The Origin and Speciation of ''Oncorhynchus'' Revisited '''in''' Strouder, D.J. ''et al.'' Eds, Pacific Salmon and Their Ecosystems: Status and Future Options. 1997. Chapman & Hall: New York, New York.

*Montgomery, David R. 2000. Coevolution of the Pacific Salmon and Pacific Rim Topography. Department of Geological Sciences, University of Washington. Available at: http://duff.ess.washington.edu/grg/publications/pdfs/salmonevolution.pdf/ Access [[August 8]], [[2006]].

*Myers, R. ''et al.'' Hatcheries and Endangered Salmon. Science. [[26 March]] [[2004]]. Vol 303: 56666, p. 1980. Available online at: http://www.sciencemag.org/cgi/content/summary/303/5666/1980?siteid=sci&ijkey=wbYfIRiC4zYWV&keytype=ref
Accessed [[August 9]], [[2006]].

*National Marine Fisheries Service. Puget Sound ESA Planning Recovery Domain. Available at: http://www.nwr.noaa.gov/Salmon-Recovery-Planning/Recovery-Domains/Puget-Sound/Index.cfm Accessed [[August 8]], [[2006]].

*National Research Council. "Upstream: Salmon and Society in the Pacific Northwest." National Academies Press, 1996, pp. 1-38.

*NOAA Fisheries, National Marine Fisheries Service. 2004. Official Press Release: NOAA Fisheries Expresses Continued Commitment to Pacific Salmon Recovery with New Hatchery Policy. [[28 March]] [[2004]]. Available online at: http://www.publicaffairs.noaa.gov/releases2004/may04/noaa04-r144.html Accessed [[August 9]], [[2004]].

*NOAA Fisheries, Office of Protected Resources. Pacific Salmonids: Major Threats and Impacts. Website. Available at: http://www.nmfs.noaa.gov/pr/species/fish/salmon.htm Accessed [[August 8]], [[2006]].

*Puget Sound Action Team, ''et al.'' 2005. Puget Sound Conservation and Recovery Plan (PSCRP). Available at: http://www.psat.wa.gov/Publications/priorities_05/pscrp_05-07_final-web.pdf/ Accessed [[August 8]], [[2006]].

*Smiley, Charles. J. Ed. Late Cenozoic History of the Pacific Northwest. American Association for the Advancement of Science: Pacific Division. Available at: http://www.sou.edu/aaaspd/TableContents/LateCenHist.pdf/ Access [[August 8]], [[2006]].

*Thanqaraju, Ranjini. “Lucrative Income From Organic Aquaculture.” New Straits Times [Kuala Lumpur] [[May 27]], [[2004]] PG 11

*Washington State Department of Ecology. Puget Sound Shorelines: Nearshore Foodweb and Eelgrass diagram. Available at: http://www.ecy.wa.gov/programs/sea/pugetsound/species/detritus.html/ Accessed [[August 8]], [[2006]].

*Washington State Department of Ecology, Shorelands Assistance Program. 2005. Washington State's Coastal and Estuarine Lands Conservation Plan. Available at: http://www.ecy.wa.gov/pubs/0506018.pdf
Accessed [[August 8]], [[2006]].
*Washington State Department of Fish and Wildlife: Commercial Fish and Shellfish (of Washington). 2006. Website: http://wdfw.wa.gov/fishcorn.htm. Accessed [[July 13]], [[2006]].

==External links==
*[http://www.nwifc.org Northwest Indian Fisheries Commission]
*[http://animaldiversity.ummz.umich.edu/site/accounts/classification/Oncorhynchus.html/ List of Pacific Ocean salmonid species]

[[Category:Environmental issues in the United States]]
[[Category:Environmental issues with fishing]]

Revision as of 14:11, 10 October 2008

Template:Geobox

The River Irwell is a river flowing through the Irwell Valley in the counties of Lancashire and Greater Manchester in England. It is one of several rivers that helped facilitate the Industrial Revolution in North West England, as a result of which it became severely polluted during the 19th century.

The river's source is at Irwell Springs on Deerplay Moor, about 1.5 miles (2.4 km) north of Bacup, in the parish of Cliviger, Lancashire. The Irwell flows through (and separates) the city centres of Manchester and Salford, before joining the River Mersey.

Course

The River Irwell is about 39 miles (63 km) in length.[1] Rising on the moors above Cliviger the Irwell flows south through Bacup, Rawtenstall, Ramsbottom and Bury before merging with the River Roch near Radcliffe. Turning west it is joined by the River Croal near Farnworth and runs south east through Kearsley, Clifton and Agecroft then meanders around Lower Broughton and Kersal, Salford Crescent and the centre of Manchester, joining the rivers Irk and Medlock. Again turning west, from Salford, it meets the Mersey south of Irlam, where the route of the river was altered in the late 19th century to form part of the course of the Manchester Ship Canal.

Natural History

Before the Industrial Revolution the Irwell was well stocked with fish, and the people who lived in the houses near Manchester Cathedral drew flagons of water from it for drinking and other domestic purposes. However, in the 19th century chemicals from the expanding industries poured into the river in increasing amounts. These pollutants were fatal to fish, the last of which were seen about 1850.[2]

The Irwell flowing past The Cliff through Kersal Dale Country Park

Despite its industrial past, fish stocks in the River Irwell are improving and brown trout are becoming an increasingly common sight. Coarse fish now predominate throughout the river's course and beyond into the Manchester Ship Canal. Water fowl, herons and cormorants are also resident on the river. New problems became apparent with the redevelopment of the Salford Quays area of the Manchester Ship Canal. Years of runoff from sewers and roads had accumulated in the slow running waters of this area and decomposition of the organic matter was causing oxygen depletion of the water. In 2001 a compressed air injection system was introduced, which raised the oxygen levels in the water by up to 300%. The resulting improvement in water quality has led to an increase in the number of invertebrate species, such as freshwater shrimp, to more than 30. Spawning and growth rates of fish species such as roach and perch have also increased to such an extent that they are now amongst the highest in England.[3]

Two Sites of Special Scientific Interest (SSSIs) are located close to the banks of the Irwell where it flows through Moses Gate Country Park, between Prestolee and Little Lever. The first is Nob End, an 8.8 hectare (21.7 acre) site which has been designated because of its biological interest, based on the predominance of flora typical of limestone grassland including some nationally rare herbs and orchids. Nob End is also designated as a Local Nature Reserve. This alkaline soil habitat was formed by the dumping of toxic alkaline waste from the Leblanc process between 1850 and 1870, which subsequently weathered into calcium carbonate, permitting the establishment of chalk-loving vegetation. Limestone grassland is not normally found in Greater Manchester, and many of these species are not found elsewhere in the county.[4][5] The second site is Ashclough, a site of geological interest that is described below in the Geology section. These two SSSIs are among the 21 found in Greater Manchester.

In Salford the river flows through Clifton Country Park and Kersal Dale Country Park, both of which have been designated as a Local Nature Reserves (LNRs).[6]

Geology

A tributary of the Irwell flowing over the new red sandstone at Clifton

The Irwell is all that remains of the shallow seas that covered most of south-east Lancashire in the Upper Carboniferous era when deposits of mud and sand were laid down. These later became beds of shales and sandstones alternating with layers of gritstone. There are also beds of new red sandstone and Manchester Marls.[7] The glaciers of the Pleistocene period further shaped the landscape and then retreated, leaving behind deposits of sand, pebbles and boulder clay that formed the fluvioglacial ridges of the Irwell Valley.[8] Ashclough, a 5.8 hectare (14.3 acre) site which comprises the steep banks of the river between Prestolee and Little Lever, has been designated a Site of Special Scientific Interest (SSSI) because of its geological interest, primarily because it is the best site in the area displaying Ashcough Marine Band and its associated strata. Ashclough is a site of national importance for interpreting the coal measure paleogeography of Great Britain.[9]

History

The River Irwell divides the cities of Salford and Manchester.
File:Irwell between manchester and salford.jpg
The Irwell at night

The origins of the name Irwell are uncertain but many accept the Anglo-Saxon origin: Ere-well, meaning "hoar or white spring".[10]

The first known human settlements were those of the Celtic tribe, the Brigantes, who farmed the uplands and lower reaches of the river. In 79 AD the Romans conquered these tribes, built forts at the confluences of the Irwell and the rivers Irk and Medlock, calling the town Mamucium.[11] They also built a ford with rectangular stone blocks at Cornbrook, which is thought to be the first man-made structure to span the river.[12] and built their villas along the river. For four hundred years the Pax Romana brought peace, but the Romans withdrew in 410 AD leaving the tribes to be overun by the Saxons who renamed the town Manigceastre. The Danes seized, and all-but destroyed, Manigceastre and the tribes were dispersed or absorbed by the Danes. The Danelaw ruled until 920 AD when the Norsemen were expelled by Edward the Elder.[13][14]

In the Middle Ages the town, which was now known as Manceastre (later to become Manchester), grew and prospered and trading vessels plied along the river.[15]

During the Industrial Revolution factories, mills and terraced hovels grew up along the river banks. Edward Corbett, the Borough Engineer of Salford wrote in his book The River Irwell published in 1907, that his father had told him that, about 1819, he had seen from the New Bailey bridge, (now Albert Bridge) in the centre of Manchester "large shoals of fish, chiefly gudgeon but also other fish, were rising to the flies." Chemicals that were dumped in the river such as gas-tar, gas-lime and ammonia water were fatal to the fish and by 1850 stacks had all disappeared. In 1860 the Irwell was described as "almost proverbial for the foulness of its waters; receiving the refuse of cotton factories, coal mines,print works, bleach works, dye works,chemical works, paper works, almost every kind of industry."[16] In the Victorian era passenger trips along the River Irwell from landing stages such as the ones at Manchester Cathedral Steps, were popular. "Sailings to Pomona Gardens were very popular with courting couples, who liked to watch the eel-catchers, admire views of Trafford Park Woodlands, and gaze at the peaceful farms and orchards. But the increasing smells from the river stopped it all".[17] The Rivers Pollution Prevention Act 1876 was designed to solve this problem, but it was largely ineffective. It did however lay the groundwork for the more draconian legislation which followed.

Since the late 19th century many attempts have made to improve the quality of the water in the Irwell. In 1891 the Mersey and Irwell Joint Committee was formed. This body ordered local authorities to provide sewage treatment facilities and industrial concerns were told to use the best practical means of preventing pollution. In 1939 this body was superseded by the Lancashire Rivers Board, but wartime conditions brought about further deterioration of the river. In 1951 the Rivers (Prevention of Pollution) Act was passed and this board disappeared to be replaced by the Mersey River Board, which was replaced in turn by the Mersey and Weaver River Authority in 1965.

A report in the Manchester Evening News in 1971 said that Bury Angling Society had signed an agreement with Bury Corporation giving them fishing rights along four miles of the river between Summerseat and Radcliffe. The secretary of the society was quoted as saying:

Extensive tests have been carried out on fish we put in the river and we are satisfied that the water will support fish life. Roach and perch have already been caught and we have had no reports of any ill-effects. There is no doubt the pollution is clearing. It will be a long job, but we are sure there is a future for angling in the river.

The report went on to say that the society "intends to carry out stocking operations soon."[18]

It was reported in the Manchester Evening News in 1972 that tiddlers had been seen swimming in the "notorious inky Irwell" near Peel Park, Salford. The Deputy chief water quality officer for Salford, Mr. Eric Harper, was quoted as saying:

"Ten years ago, any fish getting as far down as Salford would have been killed almost immediately by the pollution in the water. Although the river there is now a great deal better than it has been for 100 years, fish will probably not be able to live long. These had probably got into the main river from small streams flowing into the Irwell. But I think it is real progress."

Mr Harper went on to say that the Irwell had been well stocked with fish along its whole length 100 years ago but refused to guess when it would reach the same state again.[19]

In 1974 all the river authorities were merged into the Regional Water Authorities.[20] In the 1974 annual report of the North West Water Authority (NWWA) it was said that that the river "once internationally famous, or infamous as the epitome of river pollution, is now in a much better state as compared with its condition at the time of a special survey carried out nine years ago."[21] This was reported in an article in The Manchester Evening News on 26 October of that year which went on to say:

During nine years of pollution control work reviewed by the North West Water Authority, the biggest improvement had been in the Bolton District, where effluent from five dilapidated sewage plants and two paper mills were now being treated at the Ringley Fold Works [but] there has been little reduction in pollution from the river Roch. At Bacup the headwater of the irwell is discoloured by ochre deposits from a disused mine but work is being done to stop the ochre seepage. Fish do exist in the stretch between Rossendale and Bury and fish are to be introduced in stretches between Radcliffe and Manchester. However, it is feared that it will be many years before fish will be able to breed freely in the river

[22]

In 1980 a scheme for improving the stretch of the river for various forms of boating between Littleton Road and Adelphi Weir, in Salford, was included in Greater Manchester Policy Committee's capital programme for 1981/2. County Councillors at a recent committee meeting had criticised the state of the river, with the councillor for Oldham calling it "quite revolting and horrible". A spokesperson for the NWWA said that, although the river had a reputation for being polluted it was getting much better, but it still hadn't reached a state where they would be satisfied. She added that tests were being carried out to show the improved cleanliness of the Irwell and that 600 trout had recently been put in the river at Summerseat, near Bury. The proposals were welcomed by Salford University and Agecroft Rowing club with the University saying that they would like to use the stretch for their boat race.[23] Later that year, it was reported that hundreds of trees and shrubs were to be planted along the banks of the Irwell between Broughton and Pomona Dock, in a £650,000 "green finger" scheme to to "bring the countryside into the heart of industrial Salford"[24] The dossier outlining the scheme, prepared by Salford's Technical Services Officer, emphasised the "bleak character" of the Irwell Valley with "many constructions by the river that are decaying and rotting" and said "the main problems are caused by an excess of ammonia and a high organic content from sewage effluents which discharge into the water upstream". The report recommended that "even more support should be given to the NWWA in their pollution control of the River Irwell"[25]

During the 1980s sightings of fish in the Irwell as far downstream as the centre of Manchester were being reported in local newspapers. In February 1981 the Manchester Evening News reported that "10 Jacksharps about two inches long" had been spotted by a site manager working on the Mark Addy public house being built on New bailey Street on the border of Manchester and Salford.[26] Plans for using the river for recreation were also coming to fruition as it was reported that, on the May Bank Holiday in 1982, the first pleasure cruise of the 20th Century would leave from the New Bailey Landing Stage outside the Mark Addy public house as part of a three day experiment to see if river cruises could be a success.[27] Then, in 1983, more than 100 canal and river boats rode the flooded river for the Greater Manchester Waterways Festival, an event aimed at showing how pleasure boating could "transform the bleak waterway in the heart of Manchester"[28]

Since then there has been a gradual improvement in water quality,[29] and today wildlife is returning to the Irwell.

Mark Addy

One of the most famous characters associated with the river was Mark Addy, who was born in a tenement on The Parsonage near Blackfriars Bridge in Manchester, known as Stage Buildings. His father owned several racing boats and pleasure craft for hire on the river and, even before he learned to swim, young Mark had already saved two people from the water, one by floating out on a plank and the other by wading up to his neck in the river. He became a strong swimmer and, after he married, acquired a tavern on the Salford side of the river. Whenever anyone was in difficulties the cry would go up "Bring Mark Addy" and he would race to rescue them. He was awarded a number of medals including the gold and silver medals from the Humane Society for the Hundred of Salford, and the Royal Humane Society's bronze medal. In 1878 he became the only civilian ever to be awarded the Albert Medal (first class),[30] which was later superseded by the George Cross as the highest civilian or non-combat gallantry award in the British honours system.[31]

His last rescue was on Whit Monday 1889, when he saved a young boy from the river. He died of tuberculosis the following year, at the age of 51, by which time he had rescued over 50 people from the river.[30] There is a large memorial to him in Weaste Cemetry, Salford. The Mark Addy Footbridge crosses the Irwell between Regent Road and Pomona Docks, the Mark Addy Award (a swimming trophy) and an oil painting of him in Peel Art Gallery wearing his medals.[32] There is also a public house, named "The Mark Addy", built on the New Bailey Landing stage on the Salford side of the river near New Bailey Street.

Commerce

Barton Swing Aqueduct

Mersey and Irwell Navigation

In the late 17th century, the Warrington businessman Thomas Patten, had made the River Mersey navigable as far as Warrington and suggested that there would be significant commercial value in extending this along the Irwell as far as Manchester. In 1721, Parliament authorised the alteration with the "Mersey and Irwell Navigation Act", and by 1736 work had been completed by creating eight canal locks along the 20 miles (32 km) route from Warrington to Manchester, allowing access to boats of up to 50 long tons (51 t; 56 short tons). The waterway played a central role in the cotton industry of the 18th century that spear-headed the Industrial Revolution and was known as the Mersey & Irwell Navigation.

Bridgewater Canal

When James Brindley built the Bridgewater Canal, the task of crossing the Irwell Valley was one of the main obstacles he faced. His solution was to build a canal-carrying bridge across the river, the world's first commercially driven aqueduct. The bridge consisted of three arches, and measured 12 metres (39 ft) high, 200 metres (656 ft) long and 11 metres (36 ft) wide. Upon its opening in 1761 it earned the nickname of "the Castle in the Air" and proved hugely successful in the industry of the area. The Mersey and Irwell Navigation and the Bridgewater Canal competed for trade to and from Manchester for the next 120 years and specially designed barges with a shallow draft, known as "Mersey flats", were used on both waterways. Over the years both trade and rivalry continued to grow with each company offering reduced freight charges or special rates and concessions to gain business from the other. The most important cargo carried was raw cotton from Liverpool to Manchester but timber, dyewoods, pig iron, lead, copper, nails, tar, sand, grain and flour were also carried. Passenger services had been operating on the Bridgewater Canal for some years and in 1807 the Irwell and Mersey Navigation Company began to compete with daily services between Runcorn and Manchester. In 1816 they began to use packet steamers, however, in 1830 the Liverpool and Manchester Railway opened, packet boat services went into decline, and ceased to operate completely in the 1860s.[33] In Manchester two other canals used the Irwell as a point of access – the Manchester Bolton & Bury Canal from 1809, and the Manchester and Salford Junction Canal from 1839. Both are now non-navigable however the former is under restoration.

Manchester Ship Canal

As the 19th century progressed, the increasing need for large freight carriers led to Liverpool's dominance as a port. Manchester became increasingly reliant on its Merseyside neighbour for its export industry but the handling charges and dues charged by the Mersey Docks and Harbour Board made goods from Manchester uncompetitive. A solution was to build the Manchester Ship Canal.[34] In 1887 the Bridgewater Navigation Company was purchased by the Manchester Ship Canal Company with a cheque for £1,710,000, which was at the time the largest cheque ever written, and the building of the Manchester Ship Canal began.[35] The Ship Canal, which was made by expanding the route of the Mersey and Irwell Navigation, opened in 1894. Although it came too late to save the cotton industry that had made the region the centre of the Industrial Revolution, the canal transformed Manchester into England's third largest port, despite being 40 miles (64 km) inland. As the canal was built, it became clear that Brindley's famous aqueduct would have to be demolished, as it allowed insufficient headroom for the freighters that the canal would carry. Fortunately, in 1896 the councillors of Eccles paid to have the aqueduct moved to the spot it occupies today, alongside the canal. The Bridgewater Canal is now carried over the Irwell/Ship Canal by the equally celebrated Barton Swing Aqueduct, which was completed in 1893 with the novel idea of "opening" by rotating 90 degrees to allow ships to pass.

Ontario Basin Salford Quays

The construction of the Manchester Ship Canal and the Salford Docks led to the development of Trafford Park as a centre of heavy industry and brought employment to the area for the next eighty years. However, by the 1960s the UK began to lose its position as an industrial world power. The decline of the heavy industries in the area, the increasing size of freight carrying ships and competition from road transport, brought about the decline of Salford Docks and they eventually closed in 1982. A large urban regeneration project, The Salford Quays Development Plan, was published in 1985 and work began a few years later to redevelop the site for residential, business and leisure purposes. The Salford Quays waterside development has made living by the Irwell, and the Manchester Ship Canal into which it flows, fashionable once again.[36]

There are further plans to "turn the tide on the years of neglect and once again embrace the River Irwell as a fundamental part of Manchester and Salford's heritage and future economic and social growth. The vision is to reinvent the central Manchester conurbation as the major waterfront destination in Northern England." A number of key stakeholders are involved in the development of this regeneration vision. These include Manchester, Salford and Trafford councils, Manchester Ship Canal Company, Environment Agency, Mersey Basin Campaign, local businesses, landowners, community groups and the wider Manchester, Salford and Trafford communities.[37]

Sport on the Irwell

There has been rowing on the Irwell in Manchester and Salford since 1823. A regatta was inaugurated on 12 September 1842, on a straight course from Throstle's Nest Weir to Regent Road Bridge. Racing continued in Manchester with events such as Agecroft Regatta and Warburton Regatta. At the turn of the century, rowing was very popular in the area with many local clubs such as Nemesis, Prince of Wales, Minerva, Didsbury and Agecroft all competing regularly. However, the state of the river declined, and by the Second World War only Agecroft and Broughton rowing clubs were still active.[38]

Agecroft Rowing Club was formed in 1861, making it one of the oldest open membership rowing clubs in the world.[39] The club originally held regattas and participated in rowing events but was primarily a social club for rowing enthusiasts[40] and was based near to Agecroft Hall. It now operates from a boathouse next to the Salford Watersports Centre at Salford Quays which it shares with the University of Salford Boat Club. The boathouse also hosts the Northern Universities Boat Race, which was held on the river from 1972, but moved to the Quays in the early 1990s.[41]

Irwell Sculpture Trail

The Irwell Sculpture Trail is one of the largest public art initiatives and the longest sculpture trail in the UK.[42] The trail consists of a scenically varied, 30-mile (48 km) walking route based on the well-established Irwell Valley Way, stretching from Salford Quays to the moors above Bacup. Since 1987 over 30 pieces of public art have been commissioned from regional, national and international artists.[43]

Flood defences

The lower reaches of the Irwell have flooded many times in its history, the most well documented being the floods of 1866, 1946, 1954, 1980, and 2007. Two flood storage basins with a capacity of 650,000 cubic metres (850,000 cu yd) have been constructed to the west of Littleton Road, Kersal, at a cost of around £11 million, to alleviate the flood problem and protect some 3,000 properties in Kersal and Lower Broughton against a 1 in 75 year flood, as part of the River Irwell Flood Defence Scheme.[44] However, it is said that a 1 in a 100 year flood would breach these defences and cause some £55 million damage to property.[45] The defences proved successful on 2008-01-22, when the worst flooding to hit the region in thirty years caused the Irwell to burst its banks further downstream in the centre of Manchester.[46]

Tributaries

Moving upstream from the Mersey Confluence, the tributaries include the following: -

Confluence of the Roch and Irwell at Bury
The Irwell at Cromwell Bridge, Broughton

References

Notes

  1. ^ NDC newletter issue 9 May-June 04 Retrieved on 2008-03-21
  2. ^ Bracegirdle p.19
  3. ^ Hindle, P.(1998) (2003-08-21). "Exploring Greater Manchester — a fieldwork guide: The fluvioglacial gravel ridges of Salford and flooding on the River Irwell" (pdf). Manchester Geographical Society. Retrieved 2007-12-11.{{cite web}}: CS1 maint: numeric names: authors list (link) p.18
  4. ^ "Nob End citation sheet" (PDF). English Nature. Retrieved 2007-02-24.
  5. ^ http://biohorizons.oxfordjournals.org/cgi/content/full/1/1/61 Retrieved on 2008-05-18
  6. ^ http://www.salford.gov.uk/leisure/parks/countryparks/thecliff.htm Retrieved on 2008-01-28
  7. ^ Bracegirdle pp 15,16
  8. ^ Hindle, P.(1998) (2003-08-21). "Exploring Greater Manchester — a fieldwork guide: The fluvioglacial gravel ridges of Salford and flooding on the River Irwell" (pdf). Manchester Geographical Society. Retrieved 2007-12-11.{{cite web}}: CS1 maint: numeric names: authors list (link)
  9. ^ "Ashclough citation sheet" (PDF). English Nature. Retrieved 2007-02-24.
  10. ^ Bracegirdle p.24
  11. ^ Bracegirdle pp.16,17
  12. ^ Brereton p.6
  13. ^ Bracegirdle p.18
  14. ^ Parkinson-Bailey, John J. Manchester: An Architectural History. Manchester: Manchester University press. pp. p2. ISBN 978-0719056062. {{cite book}}: |pages= has extra text (help)
  15. ^ Bracegirdle p.18
  16. ^ Bracegirdle pp.19
  17. ^ Greater Manchester: 125 Years Images from the Manchester Evening News. The Breendon Books. 1993. p. 21. ISBN 1873626673. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help)
  18. ^ Manchester Evening News 3 December 1971
  19. ^ Manchester Evening News: "Tiddlers give new hope for cleaner "inky Irwell" but it will be a long time ahead. 25 November 1972
  20. ^ Bracegirdle pp. 153-155
  21. ^ Salford City Reporter "Notorious" river Irwell could become a pleasant stream. 1974 page 7 (date unknown)
  22. ^ Manchester Evening News Fishing in the Irwell — after 100 years 26 October 1974
  23. ^ Salford City Reporter Sailing down the Irwell on a Sunday afternoon 19 September 1980
  24. ^ Manchester Evening News Irwell revamp at £650,000 1 November 1980
  25. ^ West Manchester News Improvement scheme looks a winner 14 November 1980
  26. ^ Manchester Evening News Fish in the Irwell...it's true! 5 February 1981
  27. ^ Manchester Evening News As Salford's sailors get ready to cruise down the Irwell 23 April 1982
  28. ^ Manchester Evenng News Tide turns for the Irwell 12 September 1983
  29. ^ Anon. - "Urban Regeneration in Manchester: Tranforming the "Dark River Irwell"" (pdf). Environment Agency. Retrieved 2008-04-24. {{cite web}}: Check |url= value (help); Text "p.5" ignored (help)
  30. ^ a b Nicholls (2004), p. 64.
  31. ^ Imperial War Museum: The George Cross retrieved on 2008-08-27
  32. ^ Bracegirdle pp. 133–136.
  33. ^ History of the Mersey and Irwell Navigation
  34. ^ Worthington, Barry (2005). Discovering Manchester: A walking guide to Manchester and Salford. Wilmslow: Sigma Leisure. p. 240. ISBN 1-85058-774-4. {{cite book}}: Cite has empty unknown parameter: |coauthors= (help)
  35. ^ Canal Archive:Bridging the years
  36. ^ Burdett, Jill (2004-06-30). "Spotlight on Salford Quays" (http). Home Search. Manchester Evening News. Retrieved 2008-02-18. {{cite web}}: Cite has empty unknown parameter: |1= (help)
  37. ^ Urban River Regeneration in Manchester: Transforming the "Dark River" Irwell
  38. ^ Anon. "Rowing in Manchester:History" (http). Two Cities Boatrace. Retrieved 2008-04-25.
  39. ^ Anon. "Agecroft Rowing Club" (http). Retrieved 2008-04-24.
  40. ^ Anon. "Papers of the Agecroft Rowing Club". John Rylands University Library. Retrieved 2008-04-21.
  41. ^ Anon (2004). "Quays to Success" (PDF). Campus Report. University of Salford. Retrieved 2008-04-25.
  42. ^ Anon (2008). "Irwell Sculpture Trail" (http). Lancashire County Council website. Lancashire County Council. Retrieved 2008-05-17.
  43. ^ Morland, Joanna (2000). "Case Study: Irwell Sculpture Trail" (http). Public art online. Public Art Southwest. Retrieved 2008-05-17. {{cite web}}: Cite has empty unknown parameter: |1= (help)
  44. ^ Anon (2004-06-30). "Current flood risks and management" (PDF). River Irwell Catchment Flood Management Plan 2006. Environment Agency. Retrieved 2007-12-11. {{cite web}}: Unknown parameter |month= ignored (help)CS1 maint: date and year (link)
  45. ^ Hindle, P.(1998) (2003-08-21). "Exploring Greater Manchester — a fieldwork guide: The fluvioglacial gravel ridges of Salford and flooding on the River Irwell" (pdf). Manchester Geographical Society. Retrieved 2007-12-11.{{cite web}}: CS1 maint: numeric names: authors list (link) p.10
  46. ^ Osuh, Chris (2008-01-22). "Floods clean-up under way" (http). Manchester Evening News. M.E.N. Media. Retrieved 2008-01-26. {{cite web}}: Check date values in: |year= / |date= mismatch (help)

Bibliography

  • Bracegirdle, Cyril (1973). The Dark River. Altrincham: Sherratt. ISBN 0-85427-033-7. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
  • Nicholls, Robert (2004). Curiosities of Greater Manchester. Sutton Publishing. ISBN 0750936614.
  • Brereton, Wallace (1978). Irwell Gallery. Salford: Salford Local History Society.

External links

Gallery