Testun llawn:
Although the majority will be developable because it lies within Flood Zone 1, this large potential allocation drains in 2 directions to 2 main rivers, therefore there will be flood plain implications for the site.
A detailed level 2 FRA will be required to determine the precise flood plain extent as well as assessing site surface water drainage. The Environment Agency has hydraulic models of the river systems that can be used in the production of the site FRA.
If infiltration drainage is not possible and drainage scheme will have to ensure that the site development does not produce any cross catchment transfers. (i.e. moving surface water from one catchment to another.)
The site is sensitive in terms of protection requirements for 'Controlled Waters'. It is located on solid geology of the Bromsgrove Sandstone formation, consisting of permeable sandstone strata. These will contain sufficient groundwater to support drinking water abstractions and thus the whole formation is classified as a Principal Aquifer under the new Water Framework Directive typology. There are also permeable Sand & Gravel deposits overlying the solid geology locally and the soils predominantly consist of deep, well drained, coarse, loamy and sandy soils, with a high leaching potential. Furthermore, the site is located some 2.5 km south westerly and south easterly from two STW public supply boreholes and there is a stream adjacent to the northwest, with the river Sowe adjacent to the west.
As this is a very large 400 ha area, further site specific investigation will need to confirm the exact geology and soil conditions locally, as well as depth to water table, ground drainage potentials and any contamination legacy from previous developments (incl. historic landfill sites) or Made Ground accumulations. As part of any planning application for a residential development, we would require to see a site investigation and risk assessment to assess risks to controlled waters. Based on those findings, we can then also better advise on future drainage options (e.g. to ground or not). Again, the Environmental Health department at the Council has the remit to protect human health, so they will need to get involved too.