Nostell Priory engineering works approved to prevent loss of reservoir water in historic parkland

Planning permission has been granted to secure an embankment and dam at Nostell Priory, in Wakefield.

The work will be carried out at Middle Lake, which is part of the wider Grade II* listed historic park and gardens.

The lake is overlooked by the Manor House which is Grade I listed.

The lake is a Category C reservoir under the Reservoirs Act 1975.

The work involves the installation of an underground trench within the dam embankment.

It requires the temporary reduction in the embankment crest level which will be reinstated upon completion through engineered earthworks.

A platform will be constructed to provide 5m wide working area along the embankment crest.

All temporary works are to be removed on completion of the permanent engineering works.

A report states works are necessary to address an “ongoing seepage issue” at the lake embankment.

Following identification of the seepage in 2016, the water level of the reservoir was temporarily lowered by 0.6m in August 2020.

A Wakefield Council officer’s report recommending the scheme for approval states: “It is considered that the proposal would not have an increased impact upon the openness of the green belt, it would have no detrimental impact on the ancient woodland/historic parkland or, local biodiversity, flooding, and drainage, would not cause any highway safety issues, or land quality or stability.”

The work must be completed within three years.

A written scheme of archaeological investigation must also be submitted before the work is carried out.

Nostell Prory dates from 1733 and was built for the Winn family on the site of a medieval priory.

The Priory and its contents were given to the National Trust in 1953 by the trustees of the estate and Rowland Winn, 3rd Baron St Oswald.