Llyn Peris
Encyclopedia
Llyn Peris is a lake
in Snowdonia
, Wales
, approximately 1.8 km long and situated close to the villages of Llanberis
and Nant Peris. The lake was formed glacially and is an example of a moraine-dammed lake. Llyn Peris is named after Saint Peris
, an early Christian saint of whom little is known. The lake is flanked on one side by the mountain Elidir Fawr
and the former slate quarry of Dinorwig
. Above the opposite bank are the hills of Derlwyn and Clogwyn Mawr and a rock formation known as the Lady of Snowdon, due to its resemblance to a human face. The ruins of Dolbadarn Castle
are also located on a mound above the lake.
The lake now forms the lower reservoir of Dinorwig power station
, and the administrative buildings for the station are situated on the lake shore. Water is released into the lake from Marchlyn Mawr
(the upper reservoir) to produce electricity during periods of peak demand. This water is, in turn, pumped back to the upper reservoir using electricity purchased at off-peak periods. The water level of the lake therefore varies considerably, depending on UK electricity demand. Excess water from the lake drains into Llyn Padarn
.
During construction of the power station, when the capacity of the lake was increased considerably at this time, with the removal of a large quantity of slate waste, rare Welsh Arctic char
were removed to four other lakes in the neighbouring Carneddau
mountains, namely Ffynnon Llugwy
, Llyn Cowlyd
, Llyn Melynllyn
and Llyn Dulyn
, where they are still to be found. Although Llyn Peris itself was not restocked, some char have found their way back to the lake.
Parts of the lake shore are designated as a Site of Special Scientific Interest
for Glacial Geology.
Lake
A lake is a body of relatively still fresh or salt water of considerable size, localized in a basin, that is surrounded by land. Lakes are inland and not part of the ocean and therefore are distinct from lagoons, and are larger and deeper than ponds. Lakes can be contrasted with rivers or streams,...
in Snowdonia
Snowdonia
Snowdonia is a region in north Wales and a national park of in area. It was the first to be designated of the three National Parks in Wales, in 1951.-Name and extent:...
, Wales
Wales
Wales is a country that is part of the United Kingdom and the island of Great Britain, bordered by England to its east and the Atlantic Ocean and Irish Sea to its west. It has a population of three million, and a total area of 20,779 km²...
, approximately 1.8 km long and situated close to the villages of Llanberis
Llanberis
Llanberis is a village in Gwynedd, North Wales, lying on the southern banks of Llyn Padarn in Snowdonia. It takes its name from Saint Peris, an early Welsh saint.According to the United Kingdom Census 2001, the population of Llanberis was 1,954...
and Nant Peris. The lake was formed glacially and is an example of a moraine-dammed lake. Llyn Peris is named after Saint Peris
Saint Peris
Saint Peris was a little-known Welsh saint of the early Christian period, possibly 6th century.He is referred to in the Bonedd y Saint as a 'Cardinal of Rome'. However, he may have been one of the many children of Helig ap Glannog of Tyno Helig. He is believed to have retired to the solitude of...
, an early Christian saint of whom little is known. The lake is flanked on one side by the mountain Elidir Fawr
Elidir Fawr
Elidir Fawr is a mountain in Snowdonia, north Wales, the northernmost in the Glyderau. To the north of the summit is a small lake, Marchlyn Mawr, which is the upper reservoir for Dinorwig power station, a pump-storage power station hidden inside the mountain itself. The lower reservoir is Llyn Peris...
and the former slate quarry of Dinorwig
Dinorwig
Dinorwig is a small village located high above Llyn Padarn, near Llanberis, in Wales.It is thought that it was part of the territory of the Ordovices tribe, and that 'Dinorwig' means "Fort of the Ordovices".The village has a long history of slate quarrying...
. Above the opposite bank are the hills of Derlwyn and Clogwyn Mawr and a rock formation known as the Lady of Snowdon, due to its resemblance to a human face. The ruins of Dolbadarn Castle
Dolbadarn Castle
Dolbadarn Castle is a fortification built by the Welsh prince Llywelyn the Great during the early 13th century, at the base of the Llanberis Pass, in North Wales. The castle was important both militarily and as a symbol of Llywelyn's power and authority. The castle features a large stone keep,...
are also located on a mound above the lake.
The lake now forms the lower reservoir of Dinorwig power station
Dinorwig power station
The Dinorwig Power Station is a pumped-storage hydroelectric scheme, near Dinorwig, Llanberis in Snowdonia national park in Gwynedd, north Wales...
, and the administrative buildings for the station are situated on the lake shore. Water is released into the lake from Marchlyn Mawr
Marchlyn Mawr
Marchlyn Mawr reservoir is a high level lake in Snowdonia behind Elidir Fawr mountain. It is used as the high level water source for Dinorwig power station, a closed-loop pumped storage hydroelectric generating facility....
(the upper reservoir) to produce electricity during periods of peak demand. This water is, in turn, pumped back to the upper reservoir using electricity purchased at off-peak periods. The water level of the lake therefore varies considerably, depending on UK electricity demand. Excess water from the lake drains into Llyn Padarn
Llyn Padarn
Llyn Padarn is a glacially formed lake in Snowdonia, Gwynedd, north Wales, and is an example of a moraine dammed lake. The lake is approximately long and at its deepest point is deep. At its south-eastern end it is linked to the neighbouring Llyn Peris...
.
During construction of the power station, when the capacity of the lake was increased considerably at this time, with the removal of a large quantity of slate waste, rare Welsh Arctic char
Arctic char
Arctic char or Arctic charr is both a freshwater and saltwater fish in the Salmonidae family, native to Arctic, sub-Arctic and alpine lakes and coastal waters. No other freshwater fish is found as far north. It is the only species of fish in Lake Hazen, on Ellesmere Island in the Canadian Arctic...
were removed to four other lakes in the neighbouring Carneddau
Carneddau
The Carneddau , are a group of mountains in Snowdonia, Wales. It includes the largest contiguous areas of high ground in Wales and England, as well as six or seven of the highest peaks in the country—the Fourteen Peaks...
mountains, namely Ffynnon Llugwy
Ffynnon Llugwy
Ffynnon Llugwy is a lake in the Carneddau range of mountains in Snowdonia, North Wales.It lies at a height of about and covers an area of some...
, Llyn Cowlyd
Llyn Cowlyd
Llyn Cowlyd is the deepest lake in North Wales. It lies in the Snowdonia National Park on the edge of the Carneddau range of mountains, at a height of above sea level. The lake is long and narrow, measuring nearly long and about a third of a mile wide, and covers an area of...
, Llyn Melynllyn
Llyn Melynllyn
Llyn Melynllyn is a lake on the edge of the Carneddau range of mountains in Snowdonia, North Wales.It lies at a height of just over , and has an area of some ....
and Llyn Dulyn
Llyn Dulyn
Llyn Dulyn is a lake on the edge of the Carneddau range of mountains in Snowdonia, North Wales.The lake covers an area of only , yet is extremely deep - it reaches to a depth of 189'...
, where they are still to be found. Although Llyn Peris itself was not restocked, some char have found their way back to the lake.
Parts of the lake shore are designated as a Site of Special Scientific Interest
Site of Special Scientific Interest
A Site of Special Scientific Interest is a conservation designation denoting a protected area in the United Kingdom. SSSIs are the basic building block of site-based nature conservation legislation and most other legal nature/geological conservation designations in Great Britain are based upon...
for Glacial Geology.