The site is within Flood Zone 1 and has a low risk of flooding from fluvial (river) sources. There is no major watercourse within the immediate vicinity of the site that would pose a direct risk to the development.
The Environment Agency surface water flood mapping shows that the site is not directly impacted by surface water flooding. There are areas of surface water flood risk to the north of the site, associated with a small watercourse. As well as an overland flow path within Ashton Road that flows south-west away from the site, following the natural gradient of the road.
Surface water runoff shall look to be drained by a drainage network to an onsite attenuation (storage) basin, that at present is shown to be located adjacent to the western site boundary. The location and the sizing of the basin feature will be refined as the proposed Site Masterplan evolves.
From there surface water runoff will be discharged offsite to the watercourse to the north. This will likely be at a restricted discharge rate that will seek to match the existing greenfield runoff rate. Although this will be determined through ongoing consultation with Northamptonshire County Council, who are the Lead Local Flood Authority for the local area.
Sewer asset record plans have been obtained from Anglian Water, which show that there is a 225mm foul sewer to the north of the site, and a 150mm foul sewer to the south within Ashton Road. It is currently proposed for a connection to be made into the foul sewer within Ashton Road to discharge sewage generated by the development into. This will be subject to a Section 106 agreement with Anglian Water, who will permit any connection into their sewer asset.