Test and Itchen River Basin Catchment

We have developed the first Drainage and Wastewater Management Plan (DWMP) for the Test and Itchen River Basin Catchment.

We have 30 wastewater systems in this catchment, with 266 pumping stations and 4,563 km of sewers. We cover 11% of the geographical area (mainly the urban areas and villages including Southampton, Winchester, Andover, Romsey, Totton and Eastleigh) with 93% of the homes in the catchment connected to our wastewater systems.

Our DWMP sets out our priorities for the Test and Itchen River Basin Catchment. These include:

• Reducing the number of spills from the 62 storm overflows which together currently spill around 1000 times per annum
• Separating or attenuating excess rainwater in the sewer networks to reduce the risks of flooding and frequency of storm overflow discharges, especially in Portswood, Harestock and Stockbridge
• Investigating the potential opportunity to designate the River Itchen at Riverside Park as an inland bathing water 
• Reducing nutrient discharges from the WTWs across the river basin to prevent deterioration of the Solent and River Itchen internationally designated Habitats sites
• Planning for potential significant development at Winchester, Romsey and the Mayflower Quarter in Southampton
• Improving the resilience of our networks and treatment works to prevent pollution incidents, particularly in Harestock Amport and Barton Stacey
• Reducing the risk of sewer blockages by increasing sewer jetting and targeting customer campaigns to reduce the amount of FOG (fats, oils and grease) and unflushables in the sewer network around Kings Worthy, Basset, Harefield and Townhill Park
• Reducing the risk to groundwater by reducing leakage from our sewers in the Barton Stacey, Andover, South Wonston, Kings Worthy and Easton areas.

All the stages we followed in developing the DWMP for the Test and Itchen are set out in the subsections below. Please explore these pages to find out more. You can find detailed investment needs in the tables on the Test and Itchen Options Development and Appraisal page.