Water company's plan to stop spills into Hampshire river
The work near Romsey will ensure fewer storm water discharges
Last updated 31st Oct 2023
Southern Water has revealed plans to expand the existing West Wellow waste treatment works near Romsey to stop spills into the river Blackwater.
A planning application has been submitted to Hampshire County Council to extend the waste treatment works (WTW) as, according to the planning statement, there is “insufficient” space to accommodate the new plant and equipment within the existing site.
The work, north-east of Blackhill, currently covers 0.7 hectares and includes plant and equipment used in the wastewater treatment processes, but Southern Water wants to extend to the east.
The new consent will take effect from March 31, 2025, and the works will ensure fewer stormwater discharges to the environment due to the increased flow-to-full treatment (FFT).
That refers to the level of rain and wastewater, or flow, a sewage treatment works must treat before it is permitted to discharge excess flows to storm tanks or the environment.
Within the extended area, it is proposed to construct six SAFF units to clean water, two humus tanks to store it and an internal road to service the new infrastructure and associated below-ground pipework connections.
It is also proposed to build two kiosks within the existing operational site area, a new motor control centre (MCC) kiosk for the proposed SAFF tanks and a proposed main distribution panel (MDP) kiosk.
Additional new infrastructure will also be installed within the existing operational site, such as a pumping station, a new flume inlet works, a new SAFF pumping station, a new eight-metre diameter settlement tank and new blowers.
Due to the urgent need for these works, the construction will be built using “Southern Water’s statutory undertakers’ permitted development rights”, meaning they can go ahead without formal planning permission.
The site proposed for the WTW extension has an area of approximately 0.2 hectares, which is under the ownership of Southern Water. The eastern security fence will be removed and reinstalled at the extended WTW perimeter.
There will be an increase in traffic to and from the WTW site during the construction phase for approximately 52 weeks. During the construction phase, there will be around six to eight daily movements and two lorry movements per week.
The planning statement said: “The proposed works are necessary to enable the site to process greater volumes of wastewater and reduce the risk of storm spills from the site during heavy rainfall into the River Blackwater.
“The reduction in spill events will, therefore, provide a direct benefit to the quality of the water environment.”