Strategic Flood Risk Assessment - Hambleton District Council

THIRSK AREA
• Thirsk & Sowerby
Background
Thirsk and Sowerby are situated on a gently sloping landscape with slightly elevated ground
to the north and lower ground to the south. The area has been subject to significant flooding
on average every 25 years, with smaller scale events in between.
Cod Beck and Whitelass Beck are the main influences on flooding in Thirsk and Sowerby.
The higher risk Flood Zone 3 areas are concentrated alongside these watercourses and
extend into some existing residential areas as well as the town centre. The Flood Zone 2
areas are more extensive and cover large areas of Old Thirsk and the Industrial Park on the
eastern side of the Cod Beck.
Following the November 2000 flooding the Environment Agency carried out a Section 105
study of flooding that affects Thirsk. Following this Hambleton District Council commissioned
a two stage feasibility study to determine whether an economically viable flood alleviation
scheme could be provided for Thirsk. The feasibility study indicated that under the DEFRA
flood management grant aid funding criteria for 2005/06 it should be possible to provide an
economically viable flood alleviation scheme for Thirsk, and proposed a scheme based on a
rural water storage area combined with minimal flood defences alongside the Cod Beck
where it flows through the urban area.
Due to its strategic importance the Environment Agency are planning to enmain the Cod Beck
in April 2006. This will mean it is given main river status and will come under the supervisory
responsibility of the Environment Agency. Once this takes place only the Environment Agency
will be able to carry out flood protection works on the watercourse. Presently whilst the
watercourse retains ordinary watercourse status flood protection works fall to the Local
Authority or the Cod Beck Internal Drainage Board.
Flooding
The Flood Zone 3 areas to the north and south of existing development largely extend over
natural floodplain or washlands. Development of these areas should be avoided. The Flood
Zone 3 area extents also affect both brownfield and greenfield land within the existing
developed areas alongside the Cod Beck,
The Flood Zone 2 areas extend over a wider area of Thirsk and in some instances to
greenfield land adjacent to existing development to both the north and south of the
settlement. .The presence of the Flood Zone 2 areas does not wholly preclude development,
but does place restrictions on development subject to the sequential test set out in PPG25.
Additional areas of flood risk have not been identified.
See plans on pages 60-64
• Carlton Miniott
Background
Carlton Miniott is situated on an almost flat landscape. There are no Flood Zone 2 and 3
areas within the village, though there are a number of small drainage channels and
watercourses that flow from south to north through the village and a number of large ponds
close to residential areas.
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