List of lakes of Wales
This is a list of lakes in Wales, including those created as reservoirs. The names of most lakes in Wales start with the word "Llyn", which is Welsh for "lake". Except where otherwise referenced, all lakes listed here are named on the relevant Ordnance Survey map at 1:25000 scale.[1]
By area[]
In terms of surface area, the ten largest lakes in Wales are
- Llyn Tegid (Bala Lake) — 1,196 acres (4.84 km2)
- Llyn Trawsfynydd — 1,180 acres (4.8 km2)
- Lake Vyrnwy — 1,120 acres (4.5 km2)
- Llyn Brenig — 894 acres (3.62 km2)
- Llyn Celyn — 800 acres (3.2 km2)
- Llyn Alaw — 762 acres (3.08 km2)
- Claerwen Reservoir — 655 acres (2.65 km2)
- Llyn Clywedog — 601 acres (2.43 km2)
- Nant y Moch Reservoir — 525 acres (2.12 km2)
- — 519 acres (2.10 km2)
All of the above, with the exception of Llyn Tegid, are reservoirs held back by dams. Llyn Tegid was the largest natural lake in Wales though its level has been artificially controlled by sluices since about 1804.[2] The largest natural lake in South Wales is Llangorse Lake (Llyn Syfaddan), which is also the second largest natural lake.
By unitary authority[]
This list of Welsh lakes ordered by unitary authority includes lakes with a surface area of greater than 5 acres (2.0 ha), but excludes those lakes and ponds created as part of an active industrial site (i.e., works ponds) and also excludes service reservoirs used to store drinking water as part of the water supply system. Grid references identify the approximate centre of the lake or the dam in the case of artificial reservoirs. For some lakes the unitary authority boundary passes through a lake; in these cases the lake is represented in the list for each appropriate authority. Known occurrences include Llyn Brenig, Pontsticill Reservoir, Llwyn-on Reservoir, Cantref Reservoir and Dol-y-gaer Reservoir. All occurrences are marked with an asterisk (*).[3]
Anglesey[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| Llyn Alaw | River Alaw | SH375853 | 762 | water supply to north Anglesey |
| Llyn Bodgylched | No main catchment | SH585770 | ||
| Llyn Cefni | Afon Cefni | SH443771 | 167 | water supply to central Anglesey |
| Llyn Coron | No main catchment | SH380700 | 69 | |
| No main catchment | SH312778 | 24 | ||
| No main catchment | SH575748 | amenity (fishing) | ||
| No main catchment | SH450713 | |||
| No main catchment | SH347898 | |||
| Llyn Llywenan | No main catchment | SH347815 | Largest natural body of water on Anglesey | |
| Afon Braint | SH549786 | |||
| Llyn Maelog | No main catchment | SH325730 | 65 | former water supply to Rhosneigr |
| No main catchment | SH585751 | water supply (disused) | ||
| No main catchment | SH313770 | 55 | RSPB bird reserve | |
| No main catchment | SH425648 | |||
| Llyn Traffwll | No main catchment | SH325770 | 91 | |
| No main catchment | SH307770 | RSPB bird reserve |
Blaenau Gwent[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| (Blaen Clydach Reservoir) | Ebbw River | SO174131 | 50 | Reservoir, originally constructed in 1813
to supply the Nantyglo Ironworks.[4] |
| Ebbw River | SO164131 | reservoir | ||
| Ebbw River | SO220071 | reservoir | ||
| Ebbw River | SO160112 | |||
| Sirhowy River | SO127101 | amenity | ||
| Sirhowy River | SO129116 | reservoir |
Bridgend[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| Kenfig Pool | River Kenfig | SS797815 | 70 | natural lake |
| SS853857 | man-made dam |
Caerphilly[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| Rhymney River | SO103103 | reservoir | ||
| Rhymney River | SO098104 | reservoir | ||
| Rhymney River | SO101091 | |||
| Caerphilly Castle moat | Rhymney River | ST155872 | ||
| Sirhowy River | ST188935 | 5 | reservoir | |
| Rhymney River | SO117032 | amenity | ||
| Rhymney River | SO095072 | |||
| Rhymney River | ST154920 | angling | ||
| Rhymney River | ST155920 | angling | ||
| Pen-y-fan Pond | Sirhowy River | SO196004 | 14 | built as canal feed reservoir. |
Cardiff[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| Cardiff Bay | River Taff/River Ely | ST190726 | 500 | amenity |
| No main catchment | ST245805 | 12 | recreation and amenity | |
| Llanishen Reservoir | Rhymney River | ST185815 | 59 | water supply to Cardiff |
| Lisvane Reservoir | Rhymney River | ST189822 | water supply to Cardiff | |
| Roath lake | Rhymney River | ST184795 | 30 | recreation and amenity |
Carmarthenshire[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| Llyn Brianne | River Tywi | SN790485 | 530 | regulation reservoir |
| ? | Gwendraeth Fach | SN508142 | 5 | |
| Coastal waterbody | SS498996 | amenity (former dock) | ||
| Gwendraeth Fawr | SN568151 | amenity/reservoir | ||
| Afon Lliedi | SN519036 | ex water supply | ||
| Llyn y Fan Fach | River Tywi | SN803219 | 25 | natural |
| Afon Dulais | SN634283 | |||
| Lower Talley Lake | Afon Cothi | SN633331 | 62 | natural lake |
| Lagoons at National Wetlands Centre | Coastal waterbodies | SS529986 | conservation/wildlife | |
| /Pond Twym | Coastal lake | SN500003 | Amenity | |
| Coastal lake | SN495003 | amenity | ||
| Afon Lliedi | SN511045 | reservoir | ||
| Upper Talley Lake | Afon Cothi | SN631337 | natural lake | |
| Usk Reservoir | River Usk | SN832288 | water supply | |
| Coastal lake | SS507987 | amenity |
Ceredigion[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| River Teifi | SN788668 | natural lake | ||
| River Teifi | SN743569 | 40 | natural lake | |
| River Dyfi | SN722858 | natural lake | ||
| River Rheidol | SN748821 | hydroelectricity | ||
| River Severn | SN800698 | natural lake | ||
| River Teifi | SN792674 | water supply | ||
| Falcondale Lake | River Teifi | SN569499 | amenity | |
| River Ystwyth | SN721752 | lead mining ?/ natural | ||
| River Severn | SN796701 | natural lake | ||
| River Severn | SN800708 | natural lake | ||
| River Ystwyth | SN707752 | natural lake | ||
| River Teifi | SN786670 | water supply | ||
| River Severn | SN839729 | natural lake | ||
| River Severn | SN799647 | 70 | natural lake | |
| River Teifi | SN789676 | water supply | ||
| Nant-y-moch Reservoir | River Rheidol | SN751872 | hydroelectricity | |
| River Teifi | SN781675 | Natural | ||
| River Ystwyth | SN705759 | natural lake | ||
| River Rheidol | SN723848 | natural lake | ||
| River Teifi | SN781675 | water supply |
Conwy[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| River Clwyd | SH912594 | 65.7 | water supply | |
| Llyn Aled | River Clwyd | SH917574 | 112.7 | water supply |
| Llyn Alwen | River Dee | SH898565 | 65 | |
| Alwen Reservoir | River Dee | SH943538 | 372.9 | water supply |
| Llyn Bochlwyd | River Ogwen | SH654592 | 10 | |
| Llyn Bodgynydd | River Conwy | SH760592 | 14 | industrial supply (disused) |
| Llyn Brenig | River Dee | SH973555 | 920 | flow regulation |
| Llyn Coedty | River Conwy | SH754666 | 11.6 | hydroelectricity |
| Llyn Conwy | River Conwy | SH780462 | 101.3 | water supply for Llanrwst |
| Llyn Cowlyd | River Conwy | SH727624 | 269 | water supply for Conwy |
| Llyn Crafnant | River Conwy | SH749610 | 52 | former water supply for Trefriw and Llanrwst |
| Dulyn Reservoir | River Conwy | SH700665 | 33 | water supply |
| Llyn Eigiau | River Conwy | SH720651 | 120 | |
| Llyn Elsi | River Conwy | SH783552 | 26 | water supply for Betws-y-coed |
| Llyn Geirionydd | River Conwy | SH763608 | 45 | |
| Llyn Goddionduon | River Conwy | SH753586 | 10 | |
| River Clwyd | SH919593 | Tiny natural lake | ||
| Ffynnon Lloer | River Ogwen | SH662621 | 6 | |
| Ffynnon Llugwy | River Conwy | SH692627 | 40 | |
| Llynnau Mymbyr | River Conwy | SH708575 | 58 | |
| Llyn Ogwen | River Ogwen | SH659604 | 78 | |
| Llyn y Parc | River Conwy | SH792588 | 22 | |
| Llyn-y-foel | Afon Lledr | SH714547 | natural lake |
Denbighshire[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| River Clwyd | SJ012803 | 8.9 | Local nature reserve | |
| SH961592 | 31.4 | natural | ||
| Llyn Brenig | River Dee | SH973555 | 920 | flow regulation |
| SJ217546 | 17.5 | |||
| SJ172550 | 13.1 | |||
| SJ012402 | 6.2 | |||
| Nant-y-Ffrith Reservoir | River Cegidog | SJ242530 | 12.1 | |
| Pendinas Reservoir | River Cegidog | SJ235518 | 16.3 | |
| River Clwyd | SH999804 | 28.7 | ||
| unnamed lake on Rûg estate | River Dee | SJ058440 | 8.4 |
Flintshire[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| River Clwyd | SJ113772 | 37 | ||
| SJ278619 | 12.6 | angling | ||
| River Dee | SJ315725 | amenity | ||
| unnamed reservoir, Cilcain | SJ155641 | 5.4 | ||
| unnamed reservoir, Oakenholt | SJ262710 | 5.7 | ||
| SJ147716 | 13.8 |
Gwynedd[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| River Glaslyn | SH655479 | 10 | ||
| Afon Aber | SH698698 | 13 | water supply | |
| SH827417 | 34 | natural lake | ||
| Llyn Arenig Fawr | River Dee | SH846380 | 84 | water supply for Bala town, natural lake |
| River Dwyryd | SH710484 | 10 + 5 | industrial water supply | |
| River Mawddach | SH669264 | 6 | ||
| Llyn Bodlyn | Afon Ysgethin | SH648239 | 42 | water supply |
| River Dwyryd | SH725467 | 22 | industrial water supply. | |
| River Dwyryd | SH640350 | 5 | ||
| River Dysynni | SH714123 | 33 | ||
| Llyn Celyn | River Dee | SH860405 | 815 | river regulation |
| River Dwyryd | SH674473 | 18 | ||
| River Dwyryd | SH758387 | 8 | ||
| also written as Creiglyn Dyfi | River Dyfi | SH867225 | 15 | natural corrie lake |
| River Glaslyn | SH661457 | 5 | ||
| Afon Dwyryd | SH663470 | 7 | industrial water supply (disused) | |
| Llyn Cwellyn | Afon Gwyrfai | SH559549 | 215 | water supply, natural |
| Llyn Cwm Bychan | Afon Artro | SH640312 | 25 | |
| Afon Llyfni | SH492495 | 34 | water supply | |
| Llyn Cwmffynnon | River Conwy | SH649562 | 20 | |
| River Mawddach | SH678237 | 14 | ||
| River Dwyryd | SH677463 | 22 | ||
| Afon Llyfni | SH513508 | 15 + 15 | ||
| River Glaslyn | SH655468 | 8 | ||
| River Dwyfor | SH561444 | 98 | natural lake | |
| River Mawddach | SH737207 | 26 | amenity | |
| Llyn Dinas | River Glaslyn | SH616495 | 60 | natural lake |
| River Conwy | SH682537 | 19 + 13 | natural lakes | |
| Llyn Dulyn | Afon Ysgethin | SH661244 | 5 | natural lake, reservoir |
| River Seiont | SH600557 | 5 | natural lake | |
| River Seiont | SH570580 | 24 | ||
| Afon Gwyrfai | SH560534 | 40 | ||
| River Glaslyn | SH663497 | 10 | ||
| Afon Artro | SH646338 | 22 | ||
| Afon Gwyrfai | SH591553 | 10 | ||
| Afon Gwyrfai | SH568521 | 50 | ||
| Llyn Gwynant | River Glaslyn | SH644519 | 85 | |
| River Dee | SH885442 | 5 | ||
| SH663266 | 13 | |||
| Llyn Idwal | River Ogwen | SH645596 | 28 | |
| Afon Ysgethin | SH629222 | natural lake | ||
| River Glaslyn | SH649482 | 8 | ||
| Llyn Llydaw | River Glaslyn | SH629543 | 110 | |
| River Glaslyn | SH562499 | 6 | ||
| Llyn Mair | River Dwyryd | SH652412 | 14 | Artificial lake |
| River Dwyryd | SH717449 | 16[5] | ||
| River Seiont | SH607625 | |||
| Marchlyn Mawr | River Seiont | SH615622 | hydroelectricity | |
| Llyn Mwyngil (Talyllyn Lake) | River Dysynni | SH717099 | 220 | |
| Llyn Nantlle Uchaf | Afon Llyfni | SH514530 | 80 | |
| River Dwyryd | SH722471 | 12 | ||
| Llyn Peris | River Seiont | SH591595 | 95 | lower reservoir for pump storage hydro-electricity |
| Llyn Padarn | River Seiont | SH572613 | 280 | natural lake used for recreation |
| Tanygrisiau Reservoir | River Dwyryd | SH679441 | 95 | |
| Llyn Tecwyn Isaf | SH629370 | 7 | ||
| Llyn Tecwyn Uchaf | River Dwyryd | SH640381 | 31 | |
| Llyn Tegid (Bala Lake) | River Dee | SH911338 | 1,196 | Largest natural water in Wales |
| River Glaslyn | SH641547 | 5 | ||
| Llyn Trawsfynydd | River Dwyryd | SH674377 | 1,180 | nuclear power (formerly) and hydroelectric energy |
| River Dee | SH788384 | 20 | ||
| Afon Mawddach | SH671162 | 6 | natural lake |
Merthyr Tydfil[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| River Taff | SO039073 | amenity | ||
| Dol-y-gaer (or Pentwyn) Reservoir * | River Taff | SO060118 | water supply | |
| Llwyn-on Reservoir * | River Taff | SO012113 | water supply | |
| River Taff | SO073083 | angling | ||
| River Taff | SO071086 | angling | ||
| Pontsticill Reservoir * | River Taff | SO060118 | water supply |
Monmouthshire[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| Llandegfedd Reservoir | River Usk | ST325985 | 434 | water supply |
| / Keepers Pond | River Usk | SO255109 | amenity, formerly served Garn-ddyrys ironworks | |
| River Usk | ST430929 | 41 | water supply |
Neath Port Talbot[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| SS817902 | reservoir | |||
| Eglwys Nunydd | River Afan | SS791855 | 260 | industrial water supply, fishing |
| River Afan | SS810857 | 5 | former millpond? | |
| River Neath | SN843043 | |||
| larger un-named lake at | River Neath | SN847043 | amenity | |
| smaller un-named lake at | River Neath | SN852045 | amenity |
Pembrokeshire[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| Bosherston Lakes | Coastal stream | SR974946 | artificial | |
| Llys-y-Frân Reservoir | Western Cleddau | SN036242 | 212 | water supply |
| Western Cleddau | SN061291 | 30 | water supply |
Powys[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| River Irfon | SN891462 | 5 | Created in 1903 by damming an oxbow of the Irfon | |
| Beacons Reservoir | River Taff | SN987182 | 52 | water supply |
| River Dyfi | SN822923 | Natural | ||
| River Severn | SN924645 | 500See note | water supply | |
| Cantref Reservoir * | River Taff | SN996154 | 42 | water supply |
| River Wye | SN856611 | tiny natural lake | ||
| Claerwen Reservoir | River Severn | SN854651 | 664 | water supply |
| Llyn Clywedog | River Severn | SN911870 | river regulation | |
| River Severn | SN893686 | 217 | water supply | |
| Cray Reservoir | River Usk | SN883220 | 100 | water supply |
| Llyn Cwm Llwch | River Usk | SO001220 | 1-2 | tiny glacier lake |
| Dol-y-gaer (or Pentwyn) Reservoir * | River Taff | SO054144 | water supply | |
| River Severn | SN911639 | 500See note | water supply | |
| River Dyfi | SN755990 | natural lake | ||
| River Dyfi | SN826941 | |||
| River Usk | SO018298 | |||
| River Wye | SO119463 | c.30 | Mesotrophic lake | |
| Llangorse Lake | River Usk | SO132266 | 327 | natural lake, largest in South Wales |
| Ebbw River | SO153141 | reservoir | ||
| Afon Tanat | SJ07143169 | natural lake | ||
| Llyn y Fan Fawr | River Tawe | SN832216 | ||
| Upper Neuadd Reservoir | River Taff | SO029188 | water supply | |
| River Severn | SN911673 | 124 | water supply | |
| Pontsticill Reservoir* | River Taff | SO060118 | water supply | |
| River Clydach | SO183153 | c.5 | natural lake | |
| Talybont Reservoir | River Usk | SO104205 | water supply | |
| River Usk | SO074264 | natural lake | ||
| Lake Vyrnwy | River Vyrnwy | SH989213 | water supply | |
| Ystradfellte Reservoir | River Neath | SN945175 | water supply |
Note: Caban Coch and Garreg-ddu reservoirs are separately named but form one contiguous area of water at normal levels. The area quoted is for the two combined. At high water levels, Pentwyn Reservoir is continuous with Pontsticill Reservoir, its dam being submerged.
Rhondda Cynon Taf[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| Cantref Reservoir * | River Taff | SN996154 | water supply | |
| Dare Valley Country Park lower lake | River Cynon | SN977028 | amenity | |
| Lluest-wen Reservoir | River Rhondda Fach | SN947017 | ||
| Llwyn-on Reservoir * | River Taff | SO012113 | 150 | water supply |
| Llyn Fawr | River Cynon | SN917034 | 24 | Natural but expanded for water supply |
| River Cynon | SN989069 | |||
| River Cynon | SN982071 | |||
| River Neath | SN938072 | |||
| ? | River Cynon | ST053970 | reservoir |
Swansea[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| Lake Fendrod | River Tawe | SS676967 | 13 | amenity |
| Lower Lliw Reservoir | SN650036 | water supply | ||
| SS503873 | >15 | natural lake | ||
| SN661062 | water supply | |||
| Tawe Barrage | River Tawe | SS664926 | amenity | |
| River Loughor | SN598056 | 10 | amenity/angling |
Torfaen[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| (lower) | Afon Lwyd | ST267971 | ||
| Afon Lwyd | SO233090 | former reservoir |
Vale of Glamorgan[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| Cosmeston Lake | ST176692 | amenity | ||
| River Ely | ST045789 | amenity and reservoir | ||
| River Ely | ST050790 | 6 | former mill pond |
Wrexham[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use |
|---|---|---|---|---|
| SJ270479 | 10.6 | |||
| Chirk Castle Lake | SJ269386 | 11.1 | ||
| SJ505386 | 8.4 | |||
| Gresford Flash | SJ346536 | 8.2 | amenity | |
| Hanmer Mere | SJ452392 | 45.2 | natural lake | |
| SJ303448 | 5.2 | |||
| SJ349529 | 14.1 | |||
| SJ267452 | 6.2 | |||
| SJ276480 | 21.3 | |||
| Wynnstay Park Lake | SJ307428 | 8.9 |
By national park[]
Lakes and reservoirs within each of Wales' three national parks.
Brecon Beacons[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use | Unitary area/s |
|---|---|---|---|---|---|
| Beacons Reservoir | River Taff | SN987182 | 52 | water supply | Powys |
| Cantref Reservoir * | River Taff | SN996154 | 42 | water supply | Powys, Rhondda Cynon Taf |
| Cray Reservoir | River Usk | SN883220 | 100 | water supply | Powys |
| Dol-y-gaer (or Pentwyn) Reservoir * | River Taff | SO054144 | water supply | Powys | |
| River Usk | SO018298 | Powys | |||
| Llangorse Lake | River Wye | SO132266 | 327 | natural lake | Powys |
| Ebbw River | SO153141 | reservoir | Powys | ||
| Llwyn-on Reservoir * | River Taff | SO012113 | 150 | water supply | Merthyr Tydfil, Rhondda Cynon Taf |
| Llyn y Fan Fawr | River Tawe | SN832216 | natural lake | Powys | |
| Upper Neuadd Reservoir | River Taff | SO029188 | water supply | Powys | |
| Pontsticill Reservoir* | River Taff | SO060118 | water supply | Merthyr Tydfil, Powys | |
| River Clydach | SO183153 | c.5 | natural lake | Powys | |
| Talybont Reservoir | River Usk | SO104205 | water supply | Powys | |
| River Usk | SO074264 | natural lake | Powys | ||
| Usk Reservoir | River Usk | SN832288 | water supply | Carmarthenshire, Powys | |
| Ystradfellte Reservoir | River Neath | SN945175 | water supply | Powys |
Pembrokeshire Coast[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use | Unitary area/s |
|---|---|---|---|---|---|
| Bosherston Lakes | Coastal stream | SR974946 | natural lakes | Pembrokeshire | |
| , Rosebush | Western Cleddau | SN061291 | 30 | water supply | Pembrokeshire |
Snowdonia[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use | unitary area/s |
|---|---|---|---|---|---|
| River Glaslyn | SH655479 | 10 | Gwynedd | ||
| Afon Aber | SH698698 | 13 | water supply | ||
| SH827417 | 34 | natural lake | Gwynedd | ||
| Llyn Arenig Fawr | River Dee | SH846380 | 84 | water supply, natural lake | Gwynedd |
| River Dwyryd | SH710484 | 10 + 5 | industrial water supply | Gwynedd | |
| River Mawddach | SH669264 | 6 | Gwynedd | ||
| Llyn Bochlwyd | River Ogwen | SH654592 | 10 | Conwy | |
| Llyn Bodgynydd | SH760592 | 14 | industrial supply (disused) | Conwy | |
| Llyn Bodlyn | Afon Ysgethin | SH648239 | 42 | water supply | Gwynedd |
| River Dwyryd | SH725467 | 22 | industrial water supply | Gwynedd | |
| River Dwyryd | SH640350 | 5 | Gwynedd | ||
| River Dysynni | SH714123 | 33 | Gwynedd | ||
| Llyn Celyn | River Dee | SH858405 | 815 | river regulation | Gwynedd |
| Llyn Coedty | River Conwy | SH754666 | 11.6 | hydroelectricity | Conwy |
| River Dwyryd | SH674473 | 18 | Gwynedd | ||
| River Dwyryd | SH758387 | 8 | Gwynedd | ||
| Llyn Conwy | River Conwy | SH780462 | 101.3 | water supply for Llanrwst | Conwy |
| Llyn Cowlyd | River Conwy | SH727624 | 269 | water supply for Conwy | Conwy |
| Llyn Crafnant | River Conwy | SH749610 | 52 | former water supply | Conwy |
| River Dyfi | SH867225 | 15 | natural corrie lake | Gwynedd | |
| River Glaslyn | SH661457 | 5 | Gwynedd | ||
| SH663470 | 7 | industrial water supply (disused) | |||
| Llyn Cwellyn | Afon Gwyrfai | SH559549 | 215 | water supply | Gwynedd |
| Llyn Cwm Bychan | Afon Artro | SH640312 | 25 | Gwynedd | |
| Afon Llyfni | SH492495 | 34 | water supply | Gwynedd | |
| Llyn Cwmffynnon | River Conwy | SH649562 | 20 | Gwynedd | |
| River Mawddach | SH678237 | 14 | Gwynedd | ||
| River Dwyryd | SH677463 | 22 | Gwynedd | ||
| Afon Llyfni | SH513508 | 15 + 15 | Gwynedd | ||
| River Glaslyn | SH655468 | 8 | Gwynedd | ||
| River Dwyfor | SH561444 | 98 | natural lake | Gwynedd | |
| River Mawddach | SH737207 | 26 | amenity | Gwynedd | |
| Llyn Dinas | River Glaslyn | SH616495 | 60 | natural lake | Gwynedd |
| River Conwy | SH682537 | 19 + 13 | natural lakes | Gwynedd | |
| Llyn Dulyn | Afon Ysgethin | SH661244 | 5 | natural lake, reservoir | Gwynedd |
| Dulyn Reservoir | River Conwy | SH700665 | 33 | water supply | Conwy |
| River Seiont | SH600557 | 5 | natural lake | Gwynedd | |
| River Seiont | SH570580 | 24 | Gwynedd | ||
| Afon Gwyrfai | SH560534 | 40 | Gwynedd | ||
| River Glaslyn | SH663497 | 10 | Gwynedd | ||
| Afon Artro | SH646338 | 22 | Gwynedd | ||
| Llyn Eigiau | River Conwy | SH720651 | 120 | Conwy | |
| Llyn Elsi | River Conwy | SH783552 | 26 | water supply | Conwy |
| Afon Gwyrfai | SH591553 | 10 | Gwynedd | ||
| Llyn-y-foel | Afon Lledr | SH714547 | natural lake | Conwy | |
| Afon Gwyrfai | SH568521 | 50 | Gwynedd | ||
| Llyn Geirionydd | River Conwy | SH763608 | 45 | Conwy | |
| Llyn Goddionduon | River Conwy | SH753586 | 10 | Conwy | |
| Llyn Gwynant | River Glaslyn | SH644519 | 85 | Gwynedd | |
| River Dee | SH885442 | 5 | Gwynedd | ||
| SH663266 | 13 | Gwynedd | |||
| Llyn Idwal | River Ogwen | SH645596 | 28 | Gwynedd | |
| Afon Ysgethin | SH629222 | natural lake | Gwynedd | ||
| River Glaslyn | SH649482 | 8 | Gwynedd | ||
| Ffynnon Lloer | River Ogwen | SH662621 | 6 | Conwy | |
| Ffynnon Llugwy | River Conwy | SH692627 | 40 | Conwy | |
| Llyn Llydaw | River Glaslyn | SH629543 | 110 | Gwynedd | |
| River Glaslyn | SH562499 | 6 | Gwynedd | ||
| Llyn Mair | River Dwyryd | SH652412 | 14 | Gwynedd | |
| River Seiont | SH607625 | Gwynedd | |||
| Marchlyn Mawr | River Seiont | SH615622 | hydroelectricity | Gwynedd | |
| Llyn Mwyngil (Talyllyn Lake) | River Dysynni | SH717099 | 220 | Gwynedd | |
| Llynnau Mymbyr | River Conwy | SH708575 | 58 | Conwy | |
| Llyn Nantlle Uchaf | Afon Llyfni | SH514530 | 80 | Gwynedd | |
| River Dwyryd | SH722471 | 12 | Gwynedd | ||
| Llyn Ogwen | River Ogwen | SH659604 | 78 | Conwy | |
| Llyn y Parc | River Conwy | SH792588 | 22 | Conwy | |
| Tanygrisiau Reservoir | River Dwyryd | SH679441 | 95 | Gwynedd | |
| Llyn Tecwyn Isaf | SH629370 | 7 | Gwynedd | ||
| Llyn Tecwyn Uchaf | River Dwyryd | SH640381 | 31 | Gwynedd | |
| Llyn Tegid – (Bala Lake) | River Dee | SH911338 | 1,196 | Gwynedd | |
| River Glaslyn | SH641547 | 5 | Gwynedd | ||
| Llyn Trawsfynydd | River Dwyryd | SH674377 | 1,180 | nuclear power (formerly) & HEP | Gwynedd |
| River Dee | SH788384 | 20 | Gwynedd | ||
| SH671163 | 6 | Gwynedd |
By supply to England[]
Most Welsh lakes supply the nation itself with water, however, there are lakes and reservoirs which supply England.[6][7]
The main reservoirs created for this purpose include:
| Reservoir name | Location | Built by | Supplies water to |
|---|---|---|---|
| Lake Vyrnwy | Powys | Liverpool Corporation | Liverpool, Cheshire and Manchester |
| Claerwen | Elan Valley reservoirs | Birmingham Corporation Water Department | Birmingham |
| Elan Valley reservoirs | Birmingham Corporation Water Department | Birmingham | |
| Elan Valley reservoirs | Birmingham Corporation Water Department | Birmingham | |
| Elan Valley reservoirs | Birmingham Corporation Water Department | Birmingham, | |
| [8] | Elan Valley reservoirs | Birmingham Corporation Water Department | Birmingham |
| Alwen Reservoir | Conwy | The Corporation of Birkenhead | Birkenhead[9] |
| Llyn Celyn (via and Bala Lake) | Gwynedd | Liverpool Corporation Waterworks | Liverpool |
| Llyn Clywedog | Powys | Reed and Mallick of Salisbury | Shropshire, West Midlands to Bristol |
Former lakes[]
| Lake name | Catchment | Grid ref. | Area (acres) | Status/Use | Unitary area |
|---|---|---|---|---|---|
| [10] | Sirhowy River | SO122100 | formerly industrial use (not same site as modern lake) | Blaenau Gwent | |
| River Clydach | SO202136 | former reservoir[11] | Blaenau Gwent | ||
| [12] | River Taff | SO062052 | formerly industrial use | Merthyr Tydfil | |
| [13] | River Taff | SO049047 | formerly industrial use | Merthyr Tydfil | |
| [14] | River Cynon | SN945060 | formerly industrial use | Rhondda Cynon Taf | |
| Lower Neuadd Reservoir | River Taff | SO030180 | former reservoir (dam breached) | Merthyr Tydfil[15] | |
| [16] | Afon Llyfni | SH506528 | natural lake | Gwynedd | |
| River Taff | SO078098 | former reservoir (dam breached) | Merthyr Tydfil | ||
| Ebbw River | SO160112 | formerly industrial use | Blaenau Gwent | ||
| [17] | Sirhowy River | SO155088 | former reservoir | Blaenau Gwent |
References[]
 |
Wikimedia Commons has media related to Lakes of Wales. |
- ^ Ordnance Survey maps. 1:25000
- ^ "Bala Bridge Sluice Gates". Royal Commission on the Ancient and Historical Monuments of Wales. 24 March 2010. Retrieved 2 September 2020.
- ^ "Bing maps". Bing. Retrieved 4 September 2020.
- ^ "Blaen-y-cwm Reservoir; Blaen Clydach Reservoir Ii (291635)". Coflein. RCAHMW. Retrieved 29 September 2021.
- ^ Llyn Manod
- ^ "UK heatwave: How much water does Wales pump to England?". bbc.co.uk. BBC. Retrieved 2 September 2020.
- ^ "Elan Valley reservoirs". People's Collection of Wales. Retrieved 2 September 2020.
- ^ "Powys Digital History Project: Elan Valley Reservoirs". Retrieved 9 May 2012.
- ^ "Future capacity to supply'". What Do They Know?. What Do They Know?. Retrieved 2 September 2020.
- ^ "Monmouthshire X.12 (Dukestown; Llechryd; Rhymni; Tredegar), Revised: 1898 to 1899, Published: 1901". Map images. National Library of Scotland. Retrieved 4 December 2020.
- ^ "Brecknockshire XLVII.3 (Bryn Mawr; Llanelli; Llangatwg), Revised: 1915, Published: 1920". Map images. Ordnance Survey at National Library of Scotland. Retrieved 4 December 2020.
- ^ "Glamorgan XII.6 (Merthyr Tudful), Revised: 1915, Published: 1919". Map images. National Library of Scotland. Retrieved 4 December 2020.
- ^ "Glamorgan XII (includes: Gelli Gaer; Merthyr Tudful.), Surveyed: 1868 to 1875, Published: 1885". Map images. National Library of Scotland. Retrieved 4 December 2020.
- ^ "Glamorgan XI.5 (Aberdar; Penderyn; Rugos), Surveyed: 1867 to 1883, Published: 1885". Map images. National Library of Scotland. Retrieved 4 December 2020.
- ^ "Welsh Water to restore reservoir to natural state". WWT. Retrieved 4 September 2020.
- ^ "Caernarvonshire XXI.SW (includes: Llandwrog; Llanllyfni.), Surveyed: 1888, Published: 1888". Map images. National Library of Scotland. Retrieved 4 December 2020.
- ^ "Monmouthshire XI.SW (includes: Ebbw Vale; Tredegar.), Revised: 1948 to 1949, Published: 1953". Map images. National Library of Scotland. Retrieved 4 December 2020.
Categories:
- Lakes of Wales
- Lists of lakes of the United Kingdom
- Lists of landforms of Wales