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Concern over extra height on dam Extra height on dam is approved
(about 10 hours later)
An electricity company wants to raise the height of a dam which feeds a hydro-electricity plant in Snowdonia. An electricity company has been given permission to raise the height of a dam which feeds a hydro-electricity plant in Snowdonia.
First Hydro wants to raise the Marchlyn Mawr dam by 2.5m (8ft 3in) to increase the amount of water it can store.First Hydro wants to raise the Marchlyn Mawr dam by 2.5m (8ft 3in) to increase the amount of water it can store.
The water is used to turn turbines at the Dinorwig Power Station to produce electricity for the National Grid.The water is used to turn turbines at the Dinorwig Power Station to produce electricity for the National Grid.
Some residents in Llanberis are worried that the increased water stored will increase the risk of flooding in the village. Villagers in Llanberis have voiced fears that greater storage of water will increase the flooding risk.
But members of Snowdonia National Park Authority said that despite letters from local people opposing the plans, they were satisfied with the answers given by the power company.
The water used is passed between the high reservoir and the lower Peris lake about 600m (1,900ft) below.The water used is passed between the high reservoir and the lower Peris lake about 600m (1,900ft) below.
'Remedial work''Remedial work'
Next to Peris lake is Llanberis lake, from where water flows into the Seiont river which travels through nearby villages on its way to the sea at Caernarfon, about five miles away.Next to Peris lake is Llanberis lake, from where water flows into the Seiont river which travels through nearby villages on its way to the sea at Caernarfon, about five miles away.
Water levels are managed under an agreement between First Hydro and the Environment Agency, so that water is not allowed into the turbines to produce electricity if the bottom lake is "full".Water levels are managed under an agreement between First Hydro and the Environment Agency, so that water is not allowed into the turbines to produce electricity if the bottom lake is "full".
Opponents claim storing more water at the top lake could place Llanberis in danger if there was an emergency and electricity was needed to be produced quickly, regardless of whether the bottom lake was full. Opponents claimed storing more water at the top lake could place Llanberis in danger if there was an emergency and electricity was needed to be produced quickly, regardless of whether the bottom lake was full.
Bob Gartside, 70, a pharmacist, voiced fears for Llanberis if electricity needed to be generated to prevent a blackout in another part of Britain. Bob Gartside, 70, a pharmacist, expressed his fears for Llanberis if electricity needed to be generated to prevent a blackout in another part of Britain.
He called for the company to carry out remedial work where the water exits Llyn Padarn and on the Seiont river.He called for the company to carry out remedial work where the water exits Llyn Padarn and on the Seiont river.
Water passes through the turbines producing electricity on the wayWater passes through the turbines producing electricity on the way
A First Hydro spokesman said storing more water at Marchlyn would allow electricity to be produced for longer periods which would "maintain the company's market competitiveness and improve security of electricity supplies across Great Britain".A First Hydro spokesman said storing more water at Marchlyn would allow electricity to be produced for longer periods which would "maintain the company's market competitiveness and improve security of electricity supplies across Great Britain".
"The station will continue to operate as a 'closed' system with a fixed volume of water between the two reservoirs."The station will continue to operate as a 'closed' system with a fixed volume of water between the two reservoirs.
"Therefore, additional water storage at Marchlyn will be achieved by pumping deeper into the lower reservoir, Llyn Peris, meaning that it would actually operate more frequently at lower levels than currently.""Therefore, additional water storage at Marchlyn will be achieved by pumping deeper into the lower reservoir, Llyn Peris, meaning that it would actually operate more frequently at lower levels than currently."
Snowdonia National Park Authority will discuss the plan on Wednesday.
Officers are recommending the go-ahead if planning conditions are kept and the authority can carry out a assessment of the area under the Habitats etc. Regulations 1994.
The plans can be seen at the visitor centre at Electric Mountain in Llanberis.