Anglian Water has breached permit covering amount of treated sewage released into River Cam since 2015
The Cambridge Waste Water Treatment Plant has been releasing more treated sewage effluent into the River Cam than its permit allows since 2015, the Environment Agency says.
The facility, located in Milton and run by Anglian Water, has been exceeding its quantity limit for treated sewage effluent, but the discharge is of a higher standard than the permit requires, the Environment Agency said, and so the environmental impact is “considered minimal”.
Anglian Water has submitted a proposal which would increase the treatment works’ discharge limit until a new facility is built, but the Environment Agency says it is awaiting a formal application.
A new waste water treatment site is expected by 2030, to make room for the North East Cambridge development of about 8,000 homes.
Anglian Water has been consulting on three potential locations for it - two between the villages of Milton and Impington, and south of Landbeach, and the third between the villages of Fen Ditton, Horningsea and Stow-cum-Quy. The latter earned 52 per cent of the vote in the public consultation.
The water company is expected to confirm which location it has chosen by the end of this month.
The current site’s permit has a dry weather flow limit, which controls how much treated sewage can be discharged into the river during periods when there is no heavy rain, and separate limits for stormier conditions. The permit breach relates to the dry weather limit.
The Environment Agency said the site “has been non-compliant with one aspect of the volume limit since 2015” and has received “formal warning letters in relation to discharges exceeding the permitted quantity”.
It said any increase granted to the permitted discharge from the site would be matched by a tightening in the minimum effluent quality so that the overall nutrient load to the River Cam was not increased.
A spokesperson for the Environment Agency said: “It is the responsibility of water companies to comply with the law and to avoid polluting the environment. As England’s environmental regulator, the Environment Agency takes pollution incidents very seriously, and all water companies have strict conditions around abstraction and discharge specified through their permits.
“We are doing everything we can, with the legal powers and resources we have, to ensure these permits are complied with, including hitting water companies with fines and enforcement undertakings for failing to comply with measures designed to protect precious rivers like the Cam.
“We know that climate change, population growth and increasing urban areas are putting pressure on sewerage capacity, but we are clear that water companies prioritise the environment while they plan for the future.”
An Anglian Water spokesperson said: “We acknowledge that we are currently exceeding our permitted dry weather flow limit at our Cambridge Waste Water Treatment Plant.
“We have already made a ‘pre-application request’ to the Environment Agency regarding an increase to this permit. We received a response on October 9 in which the Environment Agency asked that we liaise with Natural England regarding our plans before making a formal application.
“We have therefore contacted Natural England to arrange a meeting with their advisory service to discuss this application further.”