|Counties||Greater Manchester, Cheshire, Merseyside|
|- location||Stockport, Greater Manchester|
|- location||Liverpool Bay|
|Length||112 km (70 mi)|
|Basin||4,680 km2 (1,807 sq mi)|
|Official name: Mersey Estuary|
|Designated:||20 December 1995|
The River Mersey (English pronunciation: /ˈmɜːzi/) is a river in North West England. It is around 70.33 miles (113 km) long, stretching from Stockport in Greater Manchester, to Liverpool Bay. For centuries, it formed part of the boundary between the historic counties of Lancashire and Cheshire.
The Mersey is formed from three tributaries: the River Etherow, the River Goyt, and the River Tame. The modern accepted start of the Mersey is at the confluence of the Tame and Goyt, in central Stockport, Greater Manchester. However, older definitions, and many older maps, place its start a few miles up the Goyt at Compstall; for example the 1911 Encyclopædia Britannica states "It is formed by the junction of the Goyt and the Etherow a short distance below Marple in Cheshire on the first-named stream." The 1784 John Stockdale map shows the River Mersey extending to Mottram, and forming the boundary between Cheshire and Derbyshire.
Stockport to Warrington 
From Stockport the river flows through Didsbury, Northenden, Stretford, Sale, Ashton on Mersey, Urmston and Flixton, then at Irlam flows into the Manchester Ship Canal, which is the canalised section of the River Irwell at this point. The old course of the Mersey has been obliterated by the canal past Hollins Green to Rixton although the old river bed can be seen outside Irlam and at Warburton. At Rixton the River Bollin enters the canal from the south and the Mersey leaves the canal to the north, meandering through Woolston, where the ship canal company's dredgings have formed the Woolston Eyes nature reserve and on to Warrington. The river is tidal from Howley Weir in Warrington, although high spring tides often top the weir. Before construction of the ship canal, work to improve navigation included Woolston New Cut, bypassing a meander, and Howley Lock for craft to avoid the weir; the new cut and lock are still evident. The island formed between the weir and the lock is known locally as Monkey Island.
Runcorn Gap 
West of Warrington the river widens, and then narrows as it passes through the Runcorn Gap between the towns of Runcorn and Widnes, in Halton. The Manchester Ship Canal passes through the gap to the south of the river. The gap is bridged by the Silver Jubilee Bridge and Runcorn Railway Bridge. Another crossing, the Mersey Gateway road bridge is to be built east of the Runcorn Gap.
From the Runcorn Gap, the river widens into a large estuary, which is 3 miles (4.8 km) wide at its widest point near Ellesmere Port. The course of the river then heads north, with Liverpool to the east and the Wirral Peninsula to the west. The Manchester Ship Canal enters the river at Eastham Locks. The eastern part of the estuary is much affected by silting, and part of it is marked on modern maps as dry land rather than tidal. The wetlands are of importance to wildlife, and are listed as a Ramsar site.
The conurbation on both sides of the estuary is known as Merseyside. The estuary narrows between Liverpool and Birkenhead, where it is constricted to a width of 0.7 miles (1.1 km), between Albert Dock in Liverpool and the Woodside ferry terminal in Birkenhead. On the Liverpool side, Liverpool Docks stretch for over 7.5 miles (12.1 km), the largest enclosed interconnected dock system in the world. American author Herman Melville described Liverpool Docks as being comparable to the pyramids in the vast scale of their construction. The docks were built out into the river bed. The Mersey Docks and Harbour Board used granite from a quarry it owned in Scotland for construction of the quays. Birkenhead grew quickly in the 19th century following the introduction of steamships, the earliest being the wooden paddle steamer Elizabeth in 1815. Docks were developed along with a shipbuilding industry, flour milling and soap manufacture on the river's Cheshire bank.
Seaforth Dock, a freeport on the Liverpool side of the estuary where it meets Liverpool Bay, opened in 1971. The dock deals with around 500,000 containers, over 1.2 million tonnes of oil, over 2.5 million tonnes of grain and animal feed, 452,000 tonnes of wood per year. About 25% of all container traffic between the UK and USA passes through the port making it one of the most successful in the world and known as the "Atlantic Gateway". Liverpool was the first UK port with radar assisted operations.
The river empties into Liverpool Bay on the Irish Sea, after a total course of 68 miles (109 km). From 4 metres (13.1 ft) neap tide to 10 metres (32.8 ft) spring tide, the River Mersey has the second highest tidal range in Britain – second only to the River Severn. The bottleneck in the river estuary forces water to flow faster creating a deep channel at the narrows.
Strong river water currents have led to proposals for the future construction of a tidal barrage to generate electricity and create another crossing. Very high spring tides can generate a tidal bore from Hale as far upstream as Warrington.
River crossings 
The first ferry across the estuary was introduced in medieval times by monks from Birkenhead Priory. They transported travellers or accommodated them at the priory in bad weather. In the early 19th century steam operated ferries were introduced. The Mersey Ferry, managed and operated by Merseytravel, operates between Pier Head in Liverpool and Woodside in Birkenhead and Seacombe. It has become a tourist attraction offering cruises that provide an overview of the river and surrounding areas.
The Mersey Railway completed its tunnel through the estuary's underlying Triassic sandstone using manual labour in 1885. Intended as a pneumatic railway, the company opted for steam trains from its opening until it was electrified in 1903. The centre of the running tunnel is between 30 feet (9.1 m) and 70 feet (21.3 m) below the river bed. The railway is now part of the Merseyrail network. Two road tunnels pass under the estuary from Liverpool. The Queensway Tunnel opened in 1934 connecting the city to Birkenhead, and the Kingsway Tunnel, opened in 1971, connects with Wallasey.
Further upstream, the Runcorn Railway Bridge over the river at Runcorn Gap was built in the 1860s for the London and North Western Railway on the mainline between London and Liverpool. It had a cantilevered footway providing an alternative crossing to a ferry. The Silver Jubilee Bridge, completed in 1961, is immediately adjacent.
Water quality in the Mersey was severely affected by industrialisation, and in 1985, the Mersey Basin Campaign was established to improve water quality and encourage waterside regeneration. In 2002, oxygen levels that could support fish along the entire length were recorded for the first time since industry began on the Mersey. Salmon have returned to the river and have been seen jumping at Woolston and Howley Weirs between September and November. Salmon parr and smolt have been caught in the Mersey's tributaries, the River Goyt and the River Bollin. Atlantic grey seals from Liverpool Bay occasionally venture into the estuary along with bottlenose dolphin and harbour porpoise. Otter pawprints have been observed near Fiddlers Ferry.
In 2009 it was announced that the river is "cleaner than at any time since the industrial revolution" and is "now considered one of the cleanest [rivers] in the UK".
Since the construction of the Manchester Ship Canal, large commercial vessels do not usually navigate the estuary beyond Garston on the north bank, or the locks into the ship canal at Eastham. Deep-water channels are maintained to both. Until the early 20th century, commercial traffic bound for further upstream carried cargo in large flat-bottomed sailing barges known as Mersey Flats to Howley Wharf in Warrington and (via the Sankey Canal) to St Helens. Motor barges delivered to riverside factories at Warrington until at least the 1970s, but nowadays only pleasure craft and yachts use the upper estuary and the tidal river where a number of sailing clubs are based. On most high tides, seagoing yachts with masts raised can navigate as far upstream as Fiddlers Ferry – about 3.1 mi (5.0 km) downstream of Warrington – where there is a small marina accessed via a river lock. Although river craft can continue upstream to Howley Weir, there are no landing or mooring facilities. Before construction of the ship canal, a lock at Howley Weir allowed navigation further upstream via a straight "cut" avoiding a meander around Woolston.
The Mersey Valley Countryside Warden Service manages local nature reserves such as Chorlton Ees and Sale Water Park recreational sites and provides an educational service along the Mersey from Manchester to the Manchester Ship Canal. 
It is possible to canoe on parts of the river between Stockport and Carrington. Liverpool Sailing Club located at Garston Coastal Park on the north bank of the estuary has a 1000 feet slipway giving access to river for water sports.
Angling has become very popular on the river as fish such as Perch, Barbel, Grayling, Carp, Roach, Chub, Trout, Pike, Bream, Dace and Salmon can be caught. The fishing rights at Warrington is controlled by Warrington Anglers Association and a small section near Rixton is controlled by Prince Albert Angling Society but the rest of the River is owned by the Borough councils and is free Fishing.
In popular culture 
The river gave its name to the Merseybeat, developed by bands from Liverpool, notably The Beatles. In 1965 it was the subject of the top-ten hit single, "Ferry Cross the Mersey" by Gerry and the Pacemakers, and a musical film with the same name. The Liverpool poets published an anthology of their work, The Mersey Sound, in 1967.
Religious significance 
The Mersey is considered sacred by British Hindus, and worshipped in a similar way to the River Ganges. Festival of Immersion ceremonies are held annually on the river, in which clay figures representing the Hindu Lord Ganesha, the elephant deity riding a mouse, are submerged in the river from a ferry boat. Followers throw flowers, pictures and coins into the river.
From its lowest point, moving upstream, tributaries of the Mersey include:
- River Gowy
- Hornsmill Brook
- River Weaver
- Ram's Brook
- Sankey Brook
- Padgate Brook
- Morris Brook
- Spittle Brook
- Thelwall Brook
- Fishington Brook
- River Bollin
- Marsh Brook
- Red Brook
- Glaze Brook/River Glaze
- River Irwell
- Old Eea Brook
- Stromford Brook
- Chorlton Brook
- Barrow Brook
- Gatley Brook
- Micker Brook
- River Tame
- River Goyt
- Mills, A D (1998). A dictionary of English place-names. Oxford: Oxford University Press. pp. 240. ISBN 0-19-280074-4.
- Arrowsmith, Peter (1997). Stockport: a History. Stockport: Stockport Metropolitan Borough Council. p. 21. ISBN 0-905164-99-7.
- John Stockdale, 1794, Map of the Environs of Mottram-in-Longdendale
- Mersey ferries, Liverpool Museums, retrieved 24 August 2012
- River Mersey, National Oceanography Centre, retrieved 24 August 2012
- Local Newspaper history page
- Liverpool Approaches, Docks and Marina
- Warrington Background and analysis, merseyforest.org.uk, retrieved 25 August 2012
- Warrington Bridge, Engineering timelines, retrieved 25 August 2012
- "River Explorer Cruises". Mersey Ferries. Retrieved 27 August 2012.
- Mersey Railway, Engineering Timelines, retrieved 25 August 2012
- Runcorn Rail Bridge, Engineering Timelines, retrieved 25 August 2012
- Runcorn Widnes Road Bridge, English Heritage, retrieved 25 August 2012
- M6 Warrington to Preston (J20 to J29), accessed on 4 August 2012
- "Mersey cleanest for 200 years". BBC News. 9 May 2003.
- environment-agency.gov.uk ""Salmon behaviour in the Mersey Catchment" at environment-agency.gov.uk
- Atlantic grey seal, Cheshire Region Biodiversity Project, retrieved 25 August 2012
- Otters return to once-polluted River Mersey, The BBC, retrieved 25 August 2012
- Smith, Mark (24 September 2009). "Mersey 'cleanest since industrial revolution'". Runcorn Weekly News (Trinity Mirror North West & North Wales). p. 7.
- Discovering the Channel, isle-of-man.com, retrieved 25 August 2012
- Welcome to the Mersey Valley Countryside Warden Service, Mersey Valley Countryside Warden Service, retrieved 27 August 2012
- Canoe trail of the River Mersey, Canoe England, retrieved 27 August 2012
- Liverpool Sailing Club, Liverpool Sailing Club, retrieved 27 August 2012
- Tall Ships to return to Liverpool after River Mersey event added, Liverpool Daily Post, retrieved 27 August 2012
- Liverpool Daily Post: Report on 2010 event
- "River marks religious ceremony". BBC News. 14 September 2008.
|Wikimedia Commons has media related to: River Mersey|
- Liverpool Pictorial
- Mersey map – aisliverpool.org.uk
- River Mersey Information
- Howley Lock
- Mersey Shipping
- "Salmon behaviour in the Mersey Catchment" at environment-agency.gov.uk