View source for River Kennet

{{Short description|Tributary of the River Thames in Southern England}}
{{other uses|Kennet River (disambiguation)}}
{{Use dmy dates|date=January 2025}}
{{Use British English|date=August 2025}}
{{Infobox river
| name               = Kennet
| name_etymology     = Linked to place name: [[Cunetio]] (very likely from Celtic ''kūn'', hound)
<!---------------------- IMAGE & MAP -->
| image              = River Kennet west of Axford - geograph.org.uk - 1225804.jpg
| image_size         = 
| image_caption      = The Kennet near [[Axford, Wiltshire]]
| map                = Kennet_and_avon_canal_-_map.png
| map_size           = 
| map_caption        = The Avon of North Wiltshire and Somerset (to west, left) and the Kennet flowing into the Thames. Linking canal network in red.
| pushpin_map        = 
| pushpin_map_size   = 
| pushpin_map_caption= 
<!---------------------- LOCATION -->
| subdivision_type1  = Country
| subdivision_name1  = England
| subdivision_type2  = 
| subdivision_name2  = 
| subdivision_type3  = Counties
| subdivision_name3  = [[Wiltshire]], [[Berkshire]]
| subdivision_type4  = Districts / Boroughs
| subdivision_name4  = 
| subdivision_type5  = Towns
| subdivision_name5  = [[Marlborough, Wiltshire|Marlborough]], [[Hungerford]], [[Newbury, Berkshire|Newbury]], [[Reading, Berkshire|Reading]]
<!---------------------- PHYSICAL CHARACTERISTICS -->
| length             = {{convert|72|km|mi|abbr=on}} 
| width_min          = 
| width_avg          = 
| width_max          = 
| depth_min          = 
| depth_avg          = 
| depth_max          = 
| discharge1_location= [[Theale, Berkshire]]
| discharge1_min     = {{convert|0.93|m3/s|cuft/s|abbr=on}}21 August 1976
| discharge1_avg     = {{convert|9.75|m3/s|cuft/s|abbr=on}}
| discharge1_max     = {{convert|70.0|m3/s|cuft/s|abbr=on}}11 June 1971
| discharge2_location= [[Newbury, Berkshire]]
| discharge2_min     = 
| discharge2_avg     = {{convert|4.64|m3/s|cuft/s|abbr=on}}
| discharge2_max     = 
| discharge3_location= [[Knighton, Wiltshire]]
| discharge3_min     =  
| discharge3_avg     = {{convert|2.50|m3/s|cuft/s|abbr=on}}
| discharge3_max     = 
| discharge4_location= [[Marlborough, Wiltshire]]
| discharge4_min     =  
| discharge4_avg     = {{convert|0.85|m3/s|cuft/s|abbr=on}}
| discharge4_max     = 
<!---------------------- BASIN FEATURES -->
| source1            = 
| source1_location   = Swallowhead Spring, near [[Silbury Hill]], [[Wiltshire]], United Kingdom
| source1_coordinates= {{coord|51.50276|N|1.84507|W|display=inline}}
| source1_elevation  = {{convert|200|m|abbr=on}}
| mouth              = [[River Thames]]
| mouth_location     = [[Reading, Berkshire|Reading]], [[Berkshire]], United Kingdom
| mouth_coordinates  = {{coord|51.459148|N|0.94947|W|display=inline,title}}
| mouth_elevation    = {{convert|40|m|abbr=on}}
| progression        = 
| river_system       = 
| basin_size         = 
| tributaries_left   = [[River Og]], [[River Lambourn]]
| tributaries_right  = [[River Dun (River Kennet)|River Dun]], [[River Enborne]], [[Clayhill Brook]], [[Foudry Brook]]
| custom_label       = Status
| custom_data        = Largest tributary of outflow river
| extra              = 
}}

The '''Kennet''' is a tributary of the [[River Thames]] in Southern England. Most of the river is straddled by the [[North Wessex Downs]] AONB (Area of Outstanding Natural Beauty). The lower reaches have been made navigable as the '''Kennet Navigation''', which – together with the [[Avon Navigation]], the [[Kennet and Avon Canal]] and the Thames – links the cities of [[Bristol]] and [[London]].

The length from near its sources west of [[Marlborough, Wiltshire|Marlborough]], Wiltshire down to [[Woolhampton]], Berkshire is a {{convert| 111.1 |ha|acre|abbr=off|adj=on}} biological [[Site of Special Scientific Interest]] (SSSI).<ref name=dsv>{{cite web |url=  https://designatedsites.naturalengland.org.uk/SiteDetail.aspx?SiteCode=S2000164&SiteName=&countyCode=44&responsiblePerson=&SeaArea=&IFCAArea= |title=  Designated Sites View: River Kennet |series=  Sites of Special Scientific Interest |publisher=  Natural England |access-date=  23 October 2019}}</ref><ref name=map>{{cite web|url= https://magic.defra.gov.uk/MagicMap.aspx?startTopic=Designations&activelayer=sssiIndex&query=HYPERLINK%3D%272000164%27|title= Map of River Kennet|series= Sites of Special Scientific Interest|publisher= Natural England|access-date= 23 October 2019}}</ref> This is primarily from an array of rare plants and animals completely [[endemism|endemic]] to [[chalk]]y watercourses.<ref>{{cite web|url=https://designatedsites.naturalengland.org.uk/PDFsForWeb/Citation/2000164.pdf|title=River Kennet citation|series=Sites of Special Scientific Interest|publisher=Natural England|access-date=23 October 2019}}</ref>

When [[Wiltshire]] had second-tier local authorities, one, [[Kennet District]], took the name of the river.

==Etymology==
The pronunciation (and spelling) was as the Kunnit (or Cunnit).<ref name=mdbk/> This is likely derived from the Roman settlement in the upper valley floor, [[Cunetio]] (in the later large village of [[Mildenhall, Wiltshire|Mildenhall]]). Latin scholars state Cunetio is very unlikely to be a Latin derivation, meaning it is a Celtic British name, like most Roman town names in Britain.<ref name=mdbk>{{cite book | title = The Silbury Treasure | first = Michael | last = Dames | year = 1976}}</ref><ref name=mdnd>{{cite web | title = Footsteps of the Goddess in Britain and Ireland | url = http://www.second-congress-matriarchal-studies.com/dames.html | publisher = Societies of Peace – Second World Congress on Matriarchal Societies | access-date = 30 April 2007 | archive-date = 20 July 2007 | archive-url = https://web.archive.org/web/20070720002954/http://www.second-congress-matriarchal-studies.com/dames.html | url-status = live }}</ref> The frequent Celtic stem "''cun-''" means "hound", as in the modern Welsh ''ci, cŵn'' "dog".{{efn|For more details see [[:wikt:Reconstruction:Proto-Celtic/kū|Wiktionary's Proto-Celtic kū]].}}

==Course==
{{multiple image
| align = left
| image1 = Kennet Fluss1 db.jpg
| width1 = 130
| alt1 = 
| caption1 = 
| image2 = Kennet Fluss2 db.jpg
| width2 = 130
| alt2 = 
| caption2 = 
| footer = Two uppermost reaches of the River Kennet near [[Avebury]], as a stream
| direction = 
| total_width = 
}}
One of the Kennet's sources is Swallowhead Spring near [[Silbury Hill]] in Wiltshire, and others are springs north of [[Avebury]] near the small villages of Uffcott and [[Broad Hinton]]. These then converge. In these early stages, the Kennet passes close by prehistoric sites, including [[Avebury Henge]], [[West Kennet Long Barrow]] and Silbury Hill. The land drained by the headwaters normally has a deep water table (being in the [[North Wessex Downs]] which is mostly chalk as the upper subsoil), thus many stretches are [[winterbourne (stream)|winterbourne]]s when and where precipitation is low and surrounding soils are not so dense with impermeables as to form a surface [[spring (hydrology)|spring]].

The river flows through the towns of [[Marlborough, Wiltshire|Marlborough]], [[Hungerford]] and [[Newbury, Berkshire|Newbury]] before flowing into the Thames on the reach above [[Sonning Lock]] in central [[Reading, Berkshire|Reading]], Berkshire.

The [[River Og|Og]] joins at Marlborough and the [[River Dun (River Kennet)|Dun]] enters at Hungerford, followed by the [[River Lambourn]], [[River Enborne|Enborne]] and the [[Foudry Brook]]. For six miles (10&nbsp;km) west of Reading's centre, the Kennet, being barraged to maintain its longest heads of water, has a semi-natural secondary channel (a long [[leat]], a corollary), the [[Holy Brook]]. This powered the [[water mill|mills]] belonging to [[Reading Abbey]].

{{clear left}}

==Navigation{{anchor|Kennet Navigation Act 1715|River Kennet Navigation Act 1720|River Kennet Navigation Act 1720}}==
{{Infobox UK legislation
| short_title           = Kennet Navigation Act 1715
| type                  = Act
| parliament            = Parliament of Great Britain
| long_title            = An Act to make the River Kennet navigable, from Reading to Newbury, in the County of Berks.
| year                  = 1715
| citation              = [[1 Geo. 1. St. 2]]. c. ''24''
| territorial_extent    = [[Great Britain]]
| royal_assent          = 21 September 1715
| commencement          = 17 March 1715{{efn|name=StartOfSession|reference=Start of session.}}
| repeal_date           = 
| amendments            = {{ubli|[[River Kennet Navigation Act 1720]]|[[River Kennet Navigation Act 1729]]}}
| repealing_legislation = 
| related_legislation   = [[British Transport Commission Act 1956]]
| status                = Amended
| original_text         = 
| collapsed             = yes
}}
{{Infobox UK legislation
| short_title           = River Kennet Navigation Act 1720
| type                  = Act
| parliament            = Parliament of Great Britain
| long_title            = An Act for enlarging the Time for making the River Kennet navigable, from Reading to Newbury, in the County of Berks.
| year                  = 1720
| citation              = [[7 Geo. 1. St. 1]]. c. 8
| territorial_extent    = [[United Kingdom]]
| royal_assent          = 23 March 1721
| commencement          = 8 December 1720{{efn|name=StartOfSession}}
| repeal_date           = 
| amends                = [[Kennet Navigation Act 1715]]
| amendments            = [[River Kennet Navigation Act 1729]]
| status                = Amended
| original_text         = https://books.google.co.uk/books?id=n7ouAAAAIAAJ&pg=PA321
| collapsed             = yes
}}
{{Infobox UK legislation
| short_title           = River Kennet Navigation Act 1729
| type                  = Act
| parliament            = Parliament of Great Britain
| long_title            = An Act for making the Acts of the First and Seventh Years of His late Majesty's Reign, for making the River Kennet navigable, from Reading, to Newbury, in the County of Berks, more effectual.
| year                  = 1729
| citation              = [[3 Geo. 2]]. c. 35
| territorial_extent    = [[United Kingdom]]
| royal_assent          = 15 May 1730
| commencement          = 13 January 1730{{efn|name=StartOfSession}}
| repeal_date           = 
| amends                = {{ubli|[[Kennet Navigation Act 1715]]|[[River Kennet Navigation Act 1720]]}}
| amendments            = 
| repealing_legislation = 
| related_legislation   = 
| status                = Current
| original_text         = https://books.google.co.uk/books?id=SlQDAAAAQAAJ&pg=PA194
| collapsed             = yes
}}
[[File:Sulhamstead Tyle Mill Lock.JPG|thumb|alt=Narrow boat (named Toad) emerging from lock with black gates and white ends of the gate arms. Around the lock is a grassy area.|[[Tyle Mill Lock]], [[Sulhamstead]].]]
[[File:County Lock, sunset.jpg|thumb|[[County Lock]], [[Reading, Berkshire|Reading]]]]
[[File:Kennet Mouth.JPG|thumb|Kennet Mouth with bridge of the [[Great Western Railway]] by [[Brunel]], [[Reading, Berkshire|Reading]] Kennet is navigable from the junction with the Thames at Kennet Mouth near Reading, upstream to Newbury where it joins the Kennet and Avon Canal.]]

The Horseshoe Bridge at Kennet Mouth, a timber-clad iron-truss structure, was built in 1891 as a way for horses towing barges along the Thames to cross the Kennet.

Going upstream, the first mile of the river, from Kennet Mouth to the High Bridge in Reading, has been navigable since at least the 13th century, providing [[wharf]]age for both the townspeople and [[Reading Abbey]]. Originally this short stretch of navigable river was under the control of the Abbey; today, including [[Blake's Lock]], it is administered by the [[Environment Agency]] as if it were part of the River Thames.

From [[High Bridge, Reading|High Bridge]] through to Newbury, the river was made navigable between 1718 and 1723 under the supervision of the engineer [[John Hore]] of Newbury. Known as the Kennet Navigation, this stretch of the river is now administered by the [[Canal & River Trust]] as part of the [[Kennet and Avon Canal]]. Throughout the navigation, stretches of natural river bed alternate with {{convert|11|mi|km}} of artificially created [[Canal lock|lock]] cuts, and a series of locks including [[County Lock|County]], [[Fobney Lock|Fobney]], [[Southcote Lock|Southcote]], [[Burghfield Lock|Burghfield]], [[Garston Lock|Garston]], [[Sheffield Lock|Sheffield]], [[Sulhamstead Lock|Sulhamstead]] and [[Tyle Mill Lock|Tyle Mill]], to overcome a rise of {{convert|130|ft|m}}.

==Wildlife==
The River Kennet is a haven for plants and animals. Its course takes it through the North Wessex Downs Area of Outstanding Natural Beauty, and the river between Marlborough and Woolhampton is designated a [[Site of Special Scientific Interest]] (SSSI). The protection that this status affords the Kennet means that endangered species of plants and animals can be found here. The white drifts of water crowfoot (''[[Ranunculus]]'') in early summer are characteristic of chalk and limestone rivers; there are superb displays by the footbridge at [[Chilton Foliat]], and by the road bridge in [[Hungerford]].

Animal species such as the [[European water vole|water vole]], [[grass snake]], [[reed bunting]], [[brown trout]], and [[brook lamprey]] flourish here, despite being in decline in other parts of the country. [[Crayfish]] are very common in parts of the river. However, most, if not all, are now the alien [[signal crayfish|American signal crayfish]], having escaped from crayfish farms, which has replaced the native [[white-clawed crayfish]] in most southern rivers, although a small population still survives in the [[River Lambourn]]. Many hundreds of insect species can be found in and around the River Kennet. There are large hatches of [[Mayfly|mayflies]], whose long-tailed, short-lived adults are a favourite food of trout; many species of water beetle and insect larvae. [[Caddisfly|Caddisflies]] are also numerous, especially in the late summer. Alongside the river, the reed beds, grasses and other vegetation support other species, including the [[scarlet tiger moth]], [[poplar hawk moth]]s and [[privet hawk-moth|privet hawk]]s.<ref name="ARK" />

==Resource uses==
Throughout its history, water mills on the Kennet have been a source of power for pre-industrial and industrial activities. In places the river has been built up to provide an additional head of water to drive the mills. Three mills remain in Ramsbury alone, and there are many disused or former mill sites, such as at [[Southcote, Berkshire|Southcote]], [[Burghfield]], [[Sulhamstead]], [[Aldermaston]], [[Thatcham]], [[Newbury, Berkshire|Newbury]], and [[Hungerford]]. Aside from the mills, in the 17th and 18th centuries the river water was also used for the brewing and tanning industries of Ramsbury and Marlborough.<ref name="ARK" >http://www.riverkennet.org/about_river_kennet.php {{Webarchive|url=https://web.archive.org/web/20101216034122/http://www.riverkennet.org/about_river_kennet.php |date=16 December 2010 }} Action for the River Kennet website</ref>

== Water quality==
The Environment Agency measures the water quality of the river systems in England. Each is given an overall ecological status, which may be one of five levels: high, good, moderate, poor and bad. There are several components that are used to determine this, including biological status, which looks at the quantity and varieties of [[invertebrate]]s, [[angiosperm]]s and fish. Chemical status, which compares the concentrations of various chemicals against known safe concentrations, is rated good or fail.<ref>{{cite web |url=http://environment.data.gov.uk/catchment-planning/help/glossary |website=Catchment Data Explorer |title=Glossary (see Biological quality element; Chemical status; and Ecological status) |publisher=Environment Agency |date=17 February 2016}}  [[File:Open Government Licence logo.svg|30px]] Text was copied from this source, which is available under an [http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/  Open Government Licence v3.0]. © Crown copyright.</ref>

Water quality of the River Kennet in 2019:
{| class="wikitable"
|-
! Section !! Ecological<br/>Status !! Chemical<br/>Status !! Overall<br/>Status !! Length !! Catchment !! Channel
|-
| {{waterqual_title |desc= Upper Kennet to Marlborough |asset= GB106039023171}} 
| {{waterqual_mod}}
| {{waterqual_fail}}
| {{waterqual_mod}}
| {{convert| 27.878 |km|mi|abbr=on}}
| {{convert| 150.231 |km2|sqmi|abbr=on}}
|
|-
| {{waterqual_title |desc= Middle Kennet (Marlborough to Hungerford) |asset= GB106039023173}} 
| {{waterqual_good}}
| {{waterqual_fail}}
| {{waterqual_mod}} 
| {{convert| 34.037 |km|mi|abbr=on}}
| {{convert| 57.123 |km2|sqmi|abbr=on}}
| 
|-
| {{waterqual_title |desc= Middle Kennet (Hungerford to Newbury) |asset= GB106039023174}} 
| {{waterqual_mod}}
| {{waterqual_fail}}
| {{waterqual_mod}}
| {{convert| 49.227 |km|mi|abbr=on}}
| {{convert| 84.872 |km2|sqmi|abbr=on}}
| 
|-
| {{waterqual_title |desc= Kennet (Lambourn confluence to Enborne confluence) |asset= GB106039017420}} 
| {{waterqual_mod}}
| {{waterqual_fail}}
| {{waterqual_mod}}
| {{convert| 16.626 |km|mi|abbr=on}}
| {{convert| 38.254 |km2|sqmi|abbr=on}}
| 
|-
| {{waterqual_title |desc= Lower Kennet (Sheffield Bottom to Reading) |asset= GB106039023140}} 
| {{waterqual_mod}} 
| {{waterqual_fail}}
| {{waterqual_mod}}
| {{convert| 29.791 |km|mi|abbr=on}}
| {{convert| 48.887 |km2|sqmi|abbr=on}}
| 
|}

===Insect kill of July 2013===
In July 2013 the [[Environment Agency]] investigated an insect kill which resulted when a small quantity (estimated to be two teaspoonfuls (10 millilitres)), of [[chlorpyrifos]], an [[organophosphate]] [[insecticide]] used in ant poison and available in garden centres, was flushed into the river killing the [[freshwater shrimp]] and most other arthropods on the stretch of the river between [[Marlborough, Wiltshire|Marlborough]] and [[Hungerford]].<ref name=WGH71113>{{cite news|title=Effects of pollution on River Kennet beginning to come clear|url=http://www.gazetteandherald.co.uk/news/10541095.Effects_of_pollution_on_River_Kennet_beginning_to_come_clear/|access-date=14 August 2013|newspaper=The Wiltshire Gazette and Herald|date=11 July 2013|archive-date=4 October 2013|archive-url=https://web.archive.org/web/20131004223118/http://www.gazetteandherald.co.uk/news/10541095.Effects_of_pollution_on_River_Kennet_beginning_to_come_clear/|url-status=live}}</ref> The dead insects sank to the bottom of the river and rotted, resulting in a bad smell, but no fish seemed to have been killed. However, without insects and shrimps to feed on, many of the fish, birds and amphibians that use the river would be likely to fade away and die.<ref>{{Cite web |url=http://www.gazetteandherald.co.uk/news/towns/marlboroughheadlines/10541095.Effects_of_pollution_on_River_Kennet_beginning_to_come_clear/ |title=Effects of pollution on River Kennet beginning to come clear (From the Wiltshire Gazette and Herald) |date=11 July 2013 |access-date=17 August 2013 |archive-date=9 September 2013 |archive-url=https://web.archive.org/web/20130909160355/http://www.gazetteandherald.co.uk/news/towns/marlboroughheadlines/10541095.Effects_of_pollution_on_River_Kennet_beginning_to_come_clear/ |url-status=live }}</ref> The poison was [[serial dilution|diluted]] and removed by the flow of the stream.<ref name=MN71013>{{cite news|title=Public health "all clear" given on the River Kennet as the chalk stream continues to suffer|url=http://www.marlboroughnewsonline.co.uk/news/all-the-news/1920-public-health-all-clear-given-on-the-river-kennet-as-the-chalk-stream-continues-to-suffer|access-date=14 August 2013|newspaper=marlboroughnewsonline.co.uk|date=10 July 2013|author=Gerald Isaaman|archive-date=21 August 2013|archive-url=https://web.archive.org/web/20130821153701/http://www.marlboroughnewsonline.co.uk/news/all-the-news/1920-public-health-all-clear-given-on-the-river-kennet-as-the-chalk-stream-continues-to-suffer|url-status=live}}</ref>

==See also==
{{Portal|United Kingdom|Transport}}
* [[Tributaries of the River Thames]]
* [[List of rivers of England]]
* [[List of locks on the Kennet and Avon Canal]]

== Notes ==
{{Notelist}}

== References ==
{{Reflist}}

{{Commons category}}
{{River item box
|type=confluence
|river=[[River Thames]]
|upstream=[[River Pang]] (south)
|downstream=[[Berry Brook]] (north)}}
{{SSSIs Berks}} 
{{SSSIs Wilts biological}}
{{Wiltshire}}
{{Rivers and watercourses of Berkshire}}

{{Authority control}}

{{DEFAULTSORT:Kennet, River}}
[[Category:Kennet catchment| ]]
[[Category:Kennet and Avon Canal]]
[[Category:Geography of Reading, Berkshire]]
[[Category:Rivers of Berkshire]]
[[Category:Rivers of Wiltshire]]
[[Category:River navigations in the United Kingdom]]
[[Category:Sites of Special Scientific Interest in Wiltshire]]
[[Category:Sites of Special Scientific Interest in Berkshire]]
[[Category:Sites of Special Scientific Interest notified in 1995]]
[[Category:West Berkshire District]]
[[Category:Tributaries of the River Thames]]