Comment

Representation ID: 22203

Received: 16/03/2020

Respondent: Environment Agency (Eastern Region)

There are many sites within Norwich which are adjacent to the River Wensum (GNLP2137, GNLP0409R, GNLP0360, GNLP0377, GNLP0401, GNLP0068, GNLP3053), firstly we need to ensure that SuDS within the development are sufficient to protect the water quality of the River Wensum and secondly any opportunities to improve riparian habitat to mitigate against the impacts of the development would help us to secure improvements necessary to meet good WFD status and help ensure that the development does not cause any deterioration.

GNLP0377
The very east of the site allocation, adjacent to the river, lies in the present and future Flood Zones 2 and 3. Therefore there should be no development within this small section of flood zones, and the development should be sequentially sited in Flood Zone 1.
As with all development in Flood Zones, the development will need to be designed with floor levels raised 0.3m above the flood levels for the future 1% (1 in 100) annual probability flood event with 35% and ideally 65% allowances for climate change. Refuge will also need to be provided above the 0.1% (1 in 1000) annual probability 25% climate change flood levels. Compensatory flood storage will also need to be provided for any built development or land raising within the 1% (1 in 100) annual probability flood outline with 35% climate change to ensure no increase in flood risk elsewhere. This will require lowering of higher land in Flood Zone 1 to provide the compensatory flood storage.