6. Point source discharges
This section summaries mechanisms for controlling discharges and limiting or preventing pollutants entering the water.
This section provides a summary of mechanisms for controlling discharges from identifiable point sources by limiting or preventing pollutants entering the water (surface water and groundwater) through prior authorisations, general binding rules and emission controls.
Mechanisms to control point and diffuse source discharges are as follows.
Water Resources Act 1991 Works Notices under s161A: any activity polluting or likely to pollute controlled waters can be served a ‘works notice’ to prevent the activity or require certain improvements or remediate the effects of polluting activity.
Water Protection Zones under s93; can be used to implement controls on activities within a formally designated zone.
Environmental Permitting (England and Wales) Regulations 2016; it is an offence to cause or knowingly permit a water discharge activity or groundwater activity without an environmental permit, unless that activity is specifically exempted under the regulations:
- permits for point source discharges prevent pollution
- require a permit with conditions for point source discharges to surface water and to ground and groundwater
- require a permit for discharges that might lead to inputs of polluting substances to groundwater, including small sewage discharges in Source Protection Zone 1s
- allows notices to prohibit any activity that might lead to an input of a pollutant to groundwater
- requires a permit with conditions to control deliberate emissions and minimise accidental losses from major installations; conditions prevent, minimise or render emissions harmless using the best available technologies as directed in guidance notes
- requires a permit with conditions to control waste management operations
Salmon and Freshwater Fisheries Act 1975; allows for enforcement action against polluters who harm or injure fish, spawning grounds or fish food.
Control of Pollution (Silage, Slurry and Agricultural Fuel Oil) Regulations 2010; specifies the design, siting, construction and maintenance of Silage, Slurry and Agricultural Fuel Oil stores.
Control of Pollution (Oil Storage) (England) Regulations 2001; sets minimum design standards for new and existing above ground oil storage facilities.
Water Industry Act 1991 s166; requires consent or a permit for operational (construction or maintenance) discharges by water undertakers relating to water treatment.
Town and Country Planning Act 1990, Planning and Compulsory Purchase Act 2004 (as amended); Planning Act 2008 (as amended); Planning guidance provided in National Planning Policy Framework (NPPF), 2021 and supporting Planning Practice Guidance (PPG), 2019; National Policy Statements:
- planning policy contributes to the protection and improvement of the environment, principally through the consideration of appropriate uses of land
Environmental Protection Act 1990, Part 2A; controls point source discharges from historic contaminated land sites (local authorities lead, with Environment Agency regulating ‘special sites’).
Environmental Damage (Prevention and Remediation) (England) Regulations 2015; require operators to carry out measures to prevent imminent or actual damage to the environment
Marine and Coastal Access Act 2009; any decision made by decision makers that may impact the United Kingdom marine area (in this case pollution and the impact on water quality) must be in accordance with the marine plans under section 58(1)
English Marine Plan Policies for Marine Litter (ML-1) and Water Quality (WQ-1) support developments that include improvements to sewage treatment works. Marine plans also support the enhancement of water quality in WQ -1 by stating that decision-makers will support proposals that protect, enhance and restore water quality where they comply with other policies in the plans and other relevant legislation. Furthermore, Policy WQ-1 of the Marine Plans state that activities that may cause deterioration of water quality by ensuring that adverse impacts from proposals must be avoided, minimised and mitigated.
Marine Strategy Regulations 2010: from one nautical mile out to the outer limit of the United Kingdom Exclusive Economic Zone, there should be no adverse impacts on water quality.
The Urban Waste Water Treatment Regulations 1994 (as amended) regulate the collection and treatment of waste water from homes and industry. They protect the environment from the negative effects of urban waste water and discharges from certain industrial sectors, such as food and drink processing plants (some of which produce waste that has a similar polluting effect to untreated sewage). Sewerage systems must be provided, to collect sewage and convey it to treatment works whilst limiting pollution from storm overflows.
The regulations lay down minimum levels of treatment for urban waste water and emission limits for effluent discharges. These depend on the population served and the type and sensitivity of the receiving waters. Most waste water must have at least secondary treatment (biological treatment). Sensitive receiving waters are identified where sewage requires more stringent, tertiary treatment before discharge into them. One type of sensitive area is for eutrophic waters where nutrients (nitrate or phosphate) stimulate excess growth of algae and other plants damaging the water environment and its uses. Another type of sensitive area is where water is intended for abstraction for use as drinking water but nitrate levels are high. In these areas larger sewage discharges must be treated to reduce their load of nutrients. The regulations also ban the disposal of sewage sludge at sea.
Powers to permit discharges, with conditions to protect the receiving waters, are available under the Environmental Permitting (England and Wales) Regulations 2016 (see section 6.2.1).
Sewerage undertakers are required to develop a programme for improving discharges every five years. This programme, which is approved by Ofwat, the Environment Agency, Drinking Water Inspectorate and Defra, provides the mechanism for funding and implementing the changes necessary to implement the Urban Waste Water Treatment Regulations.
The Environment Act 2021 includes new duties relating to Storm Overflows:
- a duty on government to publish a plan by September 2022 to reduce sewage discharges from storm overflows
- a duty on government to report to Parliament on progress on implementing the plan
- a duty on the Environment Agency to publish data on storm overflow operation on an annual basis
- a duty on Water and Sewerage Companies to continuously monitor the receiving water quality potentially affected by storm overflows
- a duty on Water and Sewerage Companies to publish data on storm overflow operation on an annual basis and make spill information available in near real time
The Environment Agency will utilise the Water Industry National Environment Programme (WINEP) where appropriate to secure the delivery of these duties by the Water and Sewerage Companies.
The Environment Act 2021 also places new duties on Water and Sewerage Companies to engage, develop and publish Drainage and Sewer Management Plans (DSMPs). DSMPs formalise through primary legislation the current voluntary approach to developing Drainage and Waste Water Management Plans (DWMPs) that will inform Water and Sewerage Company business plans between 2025 and 2030.
There are financial incentives for sewerage undertakers to comply with permit conditions established under the Ofwat operator performance assessment scheme, which links overall service provision to the price that customers pay.
View Reducing and controlling pollution in waste water discharges sludge and septic tanks for further information.
6.2.1 Water industry planning
Discharges from the water industry can be improved by modifying environmental permits. The requirements to achieve the environmental objectives in the river basin management plans are planned through the development of the Water Industry National Environment Programme (WINEP). Water companies should embed the measures within the WINEP into their business plans. These are then submitted to Ofwat through the five yearly Price Review process. Ofwat will confirm the level of investment that water companies require to meet these environmental needs.
The WINEP for Price Review 2019 has also been used as a mechanism to plan measures to investigate discharges from sewage treatment works. The WINEP also achieves a range of other outcomes, including improvements for water resources, eel passage solutions and protected area objectives.
Water company business plans will use information from local plans, where available, to help anticipate future demand for waste water treatment and investment that may be required. Where it is justified, Development Plan policies can link the rate of planned development to the available capacity of waste water treatment infrastructure and require planning authorities to investigate further through, for example, water cycle strategies.
The PR19 Water company price review included a commitment to research the input, transport and fate of microplastics through waste water treatment processes, and those used in the treatment process. The findings will be used to inform next steps.
A water industry Strategic Steering Group (SSG) micro-plastics sub-group drives collaboration across water industry to reduce micro-plastics from waste water and explore upstream interventions. The Environment Agency are working with the SSG to develop policy options for inclusion of measures to reduce plastics in PR24.
The principle behind the Environment Agency’s regulatory approach is that emissions of plastics biobeads or other plastic media used in treatment should be limited far as reasonably practicable through containment and good management, secured through management conditions in Environmental Permitting Regulations 2016 (EPR) permits.
The Environment Agency strategy for the Safe and Sustainable Use of Sludge (published 17 March 2020) sets out the intention to bring sludge into EPR. A Statutory Instrument is proposed to move sludge to EPR. The aim is to establish regulatory control to reduce micro-plastics entering soil and water.
6.2.2 Spatial planning
The spatial planning system defined by the Town and Country Planning Act 1990; Compulsory Purchase Act 2004 (as amended) sets the framework for controlling development. The planning system makes a major contribution to protecting and improving the environment, the quality of life, and local and global ecosystems.
The NPPF states that planning policies and decisions should contribute to and enhance the environment by preventing both new and existing development from contributing to or being put at unacceptable risk from, or being adversely affected by, unacceptable levels of water pollution. Development should, wherever possible, help to improve local environmental conditions such as water quality, taking into account relevant information such as river basin management plans. It also states that planning authorities should include strategic policies which set out an overall strategy for the pattern, scale and design quality of development, and make sufficient provision for infrastructure for water supply, waste water, flood risk and coastal change management, green infrastructure, and planning measures to address climate change mitigation and adaptation.
The Planning Practice Guidance states adequate water and waste water infrastructure is needed to support sustainable development, highlights that local councils in exercising their functions should have regard to river basin management plans and advocates a catchment-based approach to managing water resources through the planning system.
Defra have produced these groundwater protection codes of practice:
Sheep dip groundwater protection code
Prevent groundwater pollution from underground fuel storage tanks
Prevent groundwater pollution from solvents
The codes of practice support the Environmental Permitting (England and Wales) Regulations 2016, and deal with design, construction, operation, management and decommissioning of the relevant facilities.
National Highways has established a register of soakaways and priority outfalls across the strategic road network in England and ranked these in accordance with the risk they may pose to underlying groundwater. This will help direct pollution prevention work.
EPR include permits, standard rules and registered exemptions.
The Water and Abandoned Metal Mines Programme, a partnership between the Environment Agency, Defra and The Coal Authority, was set up in 2011 to tackle the pollution from historic mines. Abandoned metal mines contribute up to half of the metals (for example, cadmium, lead, zinc and copper) discharged to United Kingdom rivers, streams and lakes - as much as all permitted discharges from industry combined. These metals are one of the most widespread causes of chemical pollution in rivers and can come from both point and diffuse sources.
The Coal Authority also manage the Coal Minewater Treatment Programme which is funded by the Department of Business Energy and Industrial Strategy. They now operate 44 treatment schemes across England to either prevent new pollution breakouts or remediate existing discharges on a priority basis. Pollution from coal mines is more visible and localised than metal mines as the iron rich water causes rivers to turn orange.