Reservoir Safety Improvement Works

Contract details

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ID:

166464

OCID:

ocds-kuma6s-162929

Contract type:

Works

Procedure type:

Restricted

Contract award notice ref:

JUN627234

Internal ref:

Portal Ref: 166464

Contact catergory:

C - Local contract let on behalf of one buyer

Buyer:

Awdurdod Parc Cenedlaethol Eryri

Primary CPV code:

N/a

Additional CPV code(s):

Is framework:

No

Carbon reduction plan:

Options:

Description:

Reservoirs Act 1975: Llyn Mair Reservoir, County of Gwynedd, Eryri National Park Reservoir Safety Improvement Works (MIOS) Tender Expression of Interest Stillwater Associates has been employed by Eryri National Park to oversee the implementation of reservoir safety improvement works on Llyn Mair Reservoir. The site is located close to the village of Maentwrog, NGR SH 653 412. The proposed works are the construction of a new siphon pipe to allow the reservoir level to be drawn down in case of emergencies. This is to be achieved by repurposing one of the four existing spillways (Spillway ‘C’) to contain the new HDPE siphon and then subsequently backfilling with mass concrete or aggregate depending on the location. The upstream leg of the siphon is to be installed using qualified divers with some partial demolition work undertaken to the chamber. Additionally, Spillway ‘D’ is to be abandoned in situ by forming a wall across the existing channel. The works are required to address statutory recommendations made in the interests of reservoir safety. Eryri National Park has committed to having the works completed by 31st July 2026 and it is imperative that the successful contractor delivers the works accordingly.

Purchasing team:

N/a

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Contract dates

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Date awarded:

16 June 2026

Start date:

23 June 2026

End date:

23 September 2026

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Contract extensions

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Max extension options available:

0 (months)

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Additional information

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Additional information:

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Contact details

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Contract name:

Edward Jones

Contract email:

N/a

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