Southern Water’s water recycling pilot plant was developed to provide evidence in support of, and to inform, Southern Water’s final permit application.

The Environment Agency (EA) will determine what permitting standards are required for environmental protection in line with existing legislation.

The EA will expect Southern Water to comply with any permit that is agreed to allow them to discharge recycled water into Havant Thicket reservoir.

The Environment Agency has, through its role in the Nationally Significant Infrastructure planning process, assessed potential risks of constructing the proposed water recycling plant on a former landfill.

The Environment Agency considers these risks to be manageable with appropriate design and mitigation.

Sewage discharges by Southern Water into Langstone Harbour and the Solent are permitted by the Environment Agency. The limits on these permits are informed by environmental impact assessments. If the Environment Agency finds any company breaching the conditions of their permits, they will take action, up to and including prosecution.

The Government’s Storm Overflows Discharge Reduction Plan is driving £60bn between now and 2050 to reduce the use of storm overflows, including those discharging into the Solent and Langstone Harbour.

The Environment Agency (EA) requires Southern Water Services Limited to report all pollution incidents caused by any of their assets in a timely and accurate manner, whether or not the asset benefits from an Environmental Permit.

Incidents are assessed for their potential impact on the environment. The EA reviews the circumstances and any evidence available for incidents that have the potential to cause significant impact. The EA will assess compliance with any statutory or non-statutory reporting requirements on an individual basis. Where the quality of Southern Water’s initial report is insufficient for an accurate assessment of environmental impact to be made, it will liaise with the company to obtain full details. Breaches of Environmental Permit conditions relating to reporting of incidents are dealt with in accordance with the EA’s Enforcement and Sanction Policy.

The EA records and tracks data pertaining to these incidents, including the timeliness of reporting, which forms the basis of regular performance meetings with the company. Data is also published annually in the Environmental Performance Assessment of water companies.

Southern Water operates several assets with Environmental Permits authorising the discharge of dilute storm sewage into Langstone Harbour or to the Solent during times of heavy and persistent rainfall. These discharges take place via storm overflows.

Storm sewage discharges are necessary because England has a 'combined' sewerage system in many urban centres which convey both rainwater and wastewater from toilets, bathrooms and kitchens within the same pipes to a sewage treatment works. During heavy rainfall the capacity of these pipes can be exceeded many times over. Storm overflows act as relief valves which prevent the system from overloading which would otherwise result in sewage backing up and flooding people's homes, workplaces and neighbourhoods.

Where the Environment Agency (EA) suspects or has evidence that Environmental Permit conditions have been breached, or that a polluting un-permitted discharge has occurred, the EA investigates further, taking enforcement action where appropriate in accordance with its Enforcement and Sanctions Policy.

I recognise that there is more to do with regards to the management of sewage pollution. I met water company CEOs in September and made clear that the volumes of sewage discharged into rivers and other waterways in extreme weather must be reduced. To achieve this, I have set up a new Taskforce bringing together Government, the water industry, regulators and environmental NGOs. This Taskforce will set out clear proposals to address the volumes of sewage discharged into our rivers. The Taskforce is also exploring further short-term actions water companies can take to accelerate progress on storm overflows.

The Environment Agency (EA) carries out monitoring of specific bathing waters. The nearby designated bathing waters on Hayling Island, Beachlands West, Beachlands Central and Eastoke, and those on Portsea Island, Eastney and Southsea East, all consistently achieve a water quality classification of excellent.

The list of ‘designated’ bathing waters (issued by Defra) is carefully compiled to ensure that samples are taken at the most appropriate geographical locations. Langstone Harbour is not a designated bathing water and therefore does not benefit from the bacteriological monitoring that designated bathing waters receive.

The EA does not have any evidence that storm discharges into Langstone Harbour impact any designated bathing waters.

Storm discharges may impact water quality within the harbour and so there will be an increased risk for swimmers or other recreational water users here. The harbour, as it does not contain designated bathing waters, is monitored for the purpose of protecting fish and wildlife, not people.

Storm overflows allow excess surface water and sewage to be directed away from homes during rainfall events. They are operating more frequently across the country due to housing growth and climate change. In 2019, storm overflows across the country spilled an average of 35 times each and nearly one in ten spilled more than 100 times.

Langstone Harbour is designated as a transitional waterbody under the Water Framework Directive (WFD). The Environment Agency (EA) monitors the harbour for water quality and ecology. Since the 1990s, there has been an improving trend in nutrients within the harbour. This is due in part to the transfer of the Budds Farm discharge from the north of the harbour to a long sea outfall 5 kilometres offshore. The improvement in nutrients has led to the substantial reduction in macroalgae and Langstone Harbour now consistently achieves WFD Good status for nitrogen and macroalgae.

Langstone Harbour is also a designated shellfish water under WFD. It fails the stringent WFD microbial standard in shellfish flesh. Discharges from Combined Surface water Outfalls (CSOs) are likely to be one of the sources of shellfish contamination, as sewage contains bacteria and other material that shellfish feed on which can contaminate the shellfish for a period of time. Upgrades to reduce CSO spills were proposed in Southern Water’s latest Asset Management Plan (AMP). However, this is unlikely to go ahead, as it will not be cost beneficial. The cost of infrastructure upgrades is likely to be far greater than the commercial value of harvested shellfish.

Southern Water provides the EA with a record of its storm water discharges annually, detailing frequency and duration. The most recent data for Langstone Harbour that has been fully assessed and is supplied below. The EA may request specific information at any time.

The data shows that, in 2019, the majority of storm water discharges into Langstone Harbour came from Budds Farm sewage treatment works, with 57 spills that year, totalling 617 hours.

Table 1: Storm water discharges into Langstone Harbour from Southern Water Assets 2019