On 7 July 2022, the House of Lords is scheduled to debate the impacts of the current sewage disposal rates in UK rivers and the responsibility of water companies to alleviate these impacts. The debate was tabled by Lord Oates (Liberal Democrat). This article focuses on government policy to reduce storm overflow spillages. It also provides an overview of government policy to reduce phosphorus loadings from treated wastewater.

1. How is sewage discharged into England’s waters?

1.1 Sewer system and treatment of sewage

In England the original sewer systems, designed by the Victorians, were combined, with one pipe to carry wastewater (sewage) from homes and businesses and stormwater generated by rainfall. These are called combined sewage systems. Modern sewers installed since the 1960s contain two pipes to keep separate the sewage collected from homes and businesses and the rainwater falling in built-up areas. However, because most of the sewer systems are combined, the separated rainwater pipe is at times still connected to the combined sewerage system. There are around 100,000km of combined sewers in England.

Generally, the network of sewers takes the wastewater to a sewage treatment works where it is treated and returned to inland waters and the sea. However, in certain circumstances, water companies are allowed to release untreated sewage into inland waters. These are called storm overflow discharges.

Water and sewerage services are largely provided by licensed monopoly companies. Since competition is limited, prices companies can charge their customers are controlled and regulated by Ofwat. Reviews of these price limits are set every five years, and as a result, new water company investment is planned in five-year cycles. The next price review period is 2025–2030.

1.2 Storm overflows: Disposal of untreated sewage into inland waters

Storm overflows are used to spill excess wastewater and rainwater into inland waters and the sea. They are “safety valves” used in combined sewer systems to protect properties from overloaded sewers causing flooding and sewage backing up into streets and homes during heavy storm events. Storm overflow discharges can also occur at wastewater treatment facilities. There are around 15,000 storm overflows in England and approximately 13,350 of those discharge to inland rivers.

Storm overflow releases happen when the sewerage system is at risk of being overwhelmed. Surges in flow usually occur in wet weather because of the extra volume of water passing through the sewer network. However, they can also be caused by a misuse of the system, such as people sending wet wipes, fats, and grease into the network. These clog up the pipes and reduce their capacity. The storm overflow releases are normally dilute compared to wastewater, with a very high rainwater content. They may also be screened to remove litter. However, they are untreated and contain raw sewage which has high levels of harmful pathogens, such as viruses and bacteria.

The Environment Agency (EA) regulates discharges from storm overflows by issuing environmental permits for individual storm overflows. The permits outline when they can be used, as well as how they should be monitored and managed. The EA has a range of enforcement duties, including civil sanctions such as fixed monetary penalties and compliance notices. The EA can also prosecute a water company if it believes the company has breached legislation that it enforces. Ofwat is the independent economic regulator of the water companies. It can issue enforcement orders to ensure storm overflow discharges comply with the law. Ofwat can also impose financial penalties on water companies to a maximum of 10% of their turnover (in a relevant year) if they are in breach of their statutory duties or licence conditions. Financial penalties are borne by shareholders and not customers.

Increases in population, hard surfaces, and more frequent and heavier storms have increased pressure on the sewage system, bringing the “frequency of discharges to an unacceptable level”, according to the government. Data published by the EA in 2021 showed that:

  • The average number of spills per storm overflow was 29 in 2021, compared to 33 in 2020.
  • In 2021, 5% of storm overflows recorded 100 or more spills, compared to 8% in 2020.
  • In 2021, 13% of storm overflows did not spill. This number was the same as in 2020.
  • The average duration of each spill was seven hours in 2021, compared to an average of eight hours in 2020.

Monitoring of sewage spills from storm overflows and wastewater treatment plants has improved in recent years as event duration monitors (EDMs) have been rolled out across 80% of outflows on the network since 2015. Around 13,000 EDMs had been installed by water companies by 2020. Installation across the network is due to be completed by 2023. Under the Environment Act 2021, water companies and the EA must publish monitoring data on storm overflows on an annual basis (see section 2.1 for further information).

2. What is the government’s policy on reducing water pollution from sewage disposal?

The 25-year environment plan set a goal for achieving “clean and plentiful water”, and included proposals for reducing the impact of wastewater. The plan, published in 2018 under Theresa May’s government, set goals for improving the environment “within a generation”. Boris Johnson’s government has taken forward a number of the goals and proposals in the plan.

The government’s policy is to reduce the number of storm overflows that occur and reduce their adverse impact on the environment and public health. It is also introducing targets to reduce nutrient pollutants in treated sewage that is discharged by water companies into inland waters.

In terms of investment, the government has said that between 2020 and 2025 water companies will invest £7.1bn on environmental improvements in England, including £3.1bn in storm overflow improvements.

2.1 Reducing storm overflow discharges and their adverse impacts

The government has said it recognised there needed to be a “significant step change on action to protect public health and the environment” from storm overflow discharges. In February 2022, the government set a “clear expectation” in the strategic priorities statement for Ofwat (SPS) that the regulator should prioritise action by water companies to “significantly reduce storm overflows”, and that Ofwat should ensure funding to do so is approved.

The government has stated its policy is to introduce a range of measures to reduce the frequency of storm overflow spills and their harm to the environment and public health.

Storm Overflows Taskforce

In August 2020, the government formed the Storm Overflows Taskforce with a remit to explore policy options that reduce the occurrence of storm overflow spills and any harm that is caused. It includes representatives of the water industry, the EA and Ofwat, environmental groups, and groups representing customers. In November 2021, an independent report commissioned by the taskforce found:

  • The complete separation of wastewater and stormwater systems—eliminating storm overflows—would cost between £350bn and £600bn. This could increase household bills between £569 and £999 per year. It would be “highly disruptive and complex” to deliver nationwide.
  • The costs of retaining storm overflows discharging into inland waters, but limiting their use, “vary widely depending on how frequently they operate”. Nationally applied policies and scenarios were modelled and costed between £5bn (40 spills average) and £260bn (zero spills average). The equivalent benefits are £2bn and £39bn. The impact on annual household bills could be between £9 and £495 respectively.
  • A policy focused on achieving 10 spills per year on average in sensitive rivers, such as chalk streams, would cost between £8.2bn and £16bn.
  • A focus on improving rivers known to be used for bathing to achieve an average spill frequency of five per year would cost between £8bn and £26bn.

The report estimated that if nothing was changed about the use of storm overflows, up to 83 additional water bodies would fail to achieve good ecological status by 2050 because of their impact, an increase of 13% from the baseline at the time of the report’s publication. It concluded that the deterioration was because of reduced river flows, population growth, urban creep, and changes in rainfall. It stated that for the same reasons, rivers currently used for recreation would see around a quarter of their length become unsuitable for swimming.

Environment Act 2021

The government introduced a range of measures under the Environment Act 2021 to tackle discharges from storm overflows. These included:

  • A new duty directly on water companies to secure a progressive reduction in the adverse impact of discharges from storm overflows.
  • A new duty on government to produce a statutory plan to reduce spills and their adverse impact, and report to Parliament on progress. The plan is required by 1 September 2022.
  • A requirement for government to produce a report setting out the actions that would be needed to eliminate spills from storm overflows in England, and the costs and benefits. The report is required by 1 September 2022.
  • A new duty placed on water companies and the EA to publish data on storm overflow operation on an annual basis.
  • A new duty directly on water companies to publish near real-time information on the operation of storm overflows.
  • A new duty directly on water companies to monitor the water quality upstream and downstream of storm overflows and sewage disposal works.
  • A new duty directly on water companies to produce statutory drainage and wastewater management plans. The plans must set out how the companies will manage and develop their drainage and sewer system over a minimum 25-year planning horizon, including how storm overflows will be addressed through these plans.
  • A power of direction for the government to direct water companies in relation to the actions in these drainage and sewerage management plans if they are not good enough. The government has said it will “not hesitate to use this power of direction”.

The Environment Bill was introduced in Parliament in January 2020 and received royal assent on 9 November 2021. The new statutory duty on water companies to secure a progressive reduction in the adverse impact of spills from overflows was introduced by the government during the final stages of the bill. The House of Lords had added an amendment to the bill at report stage that would have placed a legal duty on water companies to take “all reasonable steps” to avoid using storm overflows and to demonstrate progressive reductions in harm caused by discharges of untreated sewage. The secretary of state and the EA would have been given powers to enforce compliance by the companies. However, during ping pong the Commons rejected the amendment, and the government proposed an alternative amendment. This introduced the duty for companies to secure a progressive reduction in harms caused by discharges. It also gave the secretary of state and Ofwat enforcement powers. The government’s amendment was agreed to in both Houses, and the provision was added to the bill.

During the debate in the Lords on the government’s amendment, Environment Minister Lord Goldsmith of Richmond Park said that the provision meant “water companies face a choice: reduce sewage discharges or face the consequences of strong enforcement action”. In response, Shadow Spokesperson for Environment, Food and Rural Affairs Baroness Hayman of Ullock said the government needed to make sure the penalties were meaningful in order to ensure companies “change [their] behaviour”. Baroness Parminter (Liberal Democrat), chair of the House of Lords Environment and Climate Change Committee, cautioned the government that it could be “under no illusion”, that if it did not “stop these appalling sewage discharges, the public will notice”. Baroness Jones of Moulsecoomb (Green) criticised the absence of a timetable and targets and argued the provisions had “strip[ped] out some of the safeguards”. However, the Duke of Wellington (Crossbench) argued the amendment would give authorities power to take enforcement action against water companies. The Duke of Wellington had moved the original amendment in the Lords to place a statutory duty on water companies and had introduced a private member’s bill in the same parliamentary session to address the matter.

Storm overflow spills reduction plan

Under the Environment Act 2021, the government is required to publish a storm overflow discharge reduction plan by 1 September 2022. The government has stated that the plan will “set clear and enforceable targets that the water industry must meet”. On 31 March 2022, the government launched a consultation to seek views on the targets and its other core proposals. The consultation was open for 12 weeks and closed on 12 May 2022.

The main measures set out in the consultation included:

  • Time-bound targets for water companies to achieve the “complete elimination of ecological harm from storm overflows, further protect public health and limit storm overflow use”.
  • Details of how water companies will be expected to achieve these targets, such as: regulatory compliance; mapping sewer networks of overflows and separate rainwater pipes connected to the combined sewer network; reducing surface water connections to the combined sewer network; and proactively investigating “novel solutions”, making use of Ofwat’s innovation fund. Water companies will be expected to set out how they will meet their storm overflow targets in their drainage and wastewater management plans.
  • Commitments to revise guidance on how to make an application for new bathing water designation. The government said it would consider further steps to improve the timeliness and usefulness of information the public are given about water quality.

Timebound targets included:

  • By 2050, water companies can only discharge from a storm overflow where they can demonstrate there is “no local adverse ecological impact”.
  • This target must be achieved for most (75%) storm overflows spilling in or close to high priority sites. These sites include sites of special scientific interest, special areas of conservation (SAC), eutrophic sensitive areas and chalk streams.
  • By 2045, all ecological harmful discharges in or close to high priority sites must be eliminated.
  • By 2035, there must be 70% fewer discharges into bathing water.

On the issue of eliminating rainwater from the combined sewer network, the consultation set out recommendations from the Storm Overflow Taskforce:

  • Reviewing the case for implementing schedule 3 of the Flood and Water Management Act 2010. If implemented, the schedule would introduce standards for new sustainable drainage systems and a new “approving body”. It would also remove the automatic right to connect to the public sewer.
  • Giving water companies the right to repair defective drains on private property.
  • Giving water companies the right to alter drainage systems on private property to reduce impermeable areas connected to the combined sewer network.
  • Giving water companies the right to discharge water to water courses.
  • Assessing the role of highway drainage as a rainwater drainage system.

The government said it would assess the recommendations along with views from the consultation to inform the final storm overflows reduction plan.

2.2 Reducing pollution from treated wastewater

The government is also consulting on the new legally binding long-term environmental targets that are required under the Environment Act 2021. Targets must be set in four priority areas, including water quality and availability. One of the government’s proposed water targets focuses on treated wastewater. The consultation was published on 16 March 2022 and closed on 27 June 2022.

The government has proposed reducing phosphorus loadings from treated wastewater by 80% by 2037. Water companies are currently committed to reducing phosphorus levels by around 50% by 2027. The government states that the new target is more “ambitious” and longer term. It argues further action is needed because of climate change and population growth.

Continuous discharge of treated sewage is the largest source of water pollution from water companies. The government states that wastewater from the water industry is “one of the biggest pressures” on the water environment, impacting 36% of water bodies that did not achieve good status in 2019. Contained in the waste discharge from sewage works is phosphorus. Phosphorus is the main nutrient involved in eutrophication of freshwaters. Eutrophication takes place when nutrient levels are too high. It harms the quality of the water and damages the local ecology. Discharge from treated sewage is the main source of phosphorus in many water bodies. The EA reports that it accounted for 60–80% of phosphorus entering rivers in England.

Alongside the consultation document, the government published an impact assessment (IA) on its water targets. It stated the water industry will be the sector that is “directly impacted” by the wastewater target, and water companies will be responsible for implementing the changes needed to meet it. The IA explains that water companies and Ofwat will negotiate the funding mechanisms through the price review process. These will be reflected in customers’ sewerage bills.

The target will be reflected in statutory guidance from the EA to inform water company business plans. The target will be supported by requirements the EA sets in the discharge permits for sewage works. Progress against the target will be monitored by water companies under operator self-monitoring and reported to the EA. The EA will be able to take enforcement action against any water companies failing to meet agreed standards under the environmental permitting regime.

3. What has been said about sewage water pollution policy?

In January 2022, the House of Commons Environmental Audit Committee published a report on water quality in rivers. The committee found there was “mounting public concern” about sewage pollution, which was “reflected in backbench proposals” during the passage of the Environment Bill in the House of Lords. The committee concluded:

The public are rightly shocked when they discover that untreated or partially treated sewage is regularly dumped into rivers and streams in England.

The committee found that public confidence in the regulatory structures was “understandably low”. It argued that it was “vital” the public could trust regulators to ensure that high levels of water quality in rivers were achieved and maintained.

The Storm Overflow Taskforce’s independent report also considered evidence from the public and found that over a third of the public surveyed in May 2021 ranked pollution related to sewage as a “top three environmental issue”. The survey showed that 70% of the public would like remedial action focused on river ecology (including its plants and animals) rather than its aesthetic (13%) or to support safe swimming (8%).

The Environmental Audit Committee described as a “positive first step” the new statutory duty placed on water companies in England to secure a progressive reduction in the adverse impact of discharges from their storm overflows. However, the committee has highlighted the need for the government and the EA to set specific targets and timetables to inform the water company’s statutory drainage and sewage management plans. The committee recommended the government and EA “clearly indicate significant ambition” by setting “challenging” improvement targets and “stretching” timetables in the first round of the plans.

Water UK, the representative body for water and wastewater companies across the UK, also raised the need for “specific goals” and targets on what the government wanted delivered. Responding to a consultation on the SPS for Ofwat in October 2021, Water UK welcomed the approach of the government to set long-term targets. However, it said the government had “missed [an] opportunity” to “provide clear and unambiguous direction”. It cautioned that without specific goals, there was a “high likelihood that vital investment will be deferred in favour of perceived short-term pressures”. It called for the SPS to set:

[…] an explicit expectation that regulatory decisions at each price review should demonstrably set the sector on a measurable trajectory to meet these long-term targets.

Conservation organisation the River Trust expressed similar views in its response. In February 2022, it welcomed the “new emphasis on long-term thinking, innovation, and partnership”. However, the trust said it had concerns about the lack of clarity on how the aims set out in the SPS should be achieved. It called for greater detail on how “Ofwat should regulate a fundamental shift in industry trade-offs”. The trust felt the SPS was “not ambitious enough” on issues such as addressing investment gaps in ageing infrastructure.

The House of Commons Environmental Audit Committee argued that investment on infrastructure must be “accelerated”. The committee said Ofwat’s role was to prioritise the long-term investment in wastewater assets, such as storm overflows, in its price review process. The committee also recommended that through the SPS, Ofwat incentivise the use of nature-based solutions in wastewater management. Nature-based solutions help reduce pollution while also protecting, restoring or creating new wildlife habitats. The committee invited the regulator to routinely update the committee on Ofwat’s progress against the objectives of the SPS.

The committee said the government’s role was to encourage Ofwat to increase “materially the proportion of each company’s capital investment devoted to improving water quality”. The committee also called for the government to publish its assessment of “every possible option” to reduce pressures on the existing infrastructure while also assessing the case for “significant” capital work, in its statutory plan to reduce storm overflow spills.

Cover image by Matthew Feeney on Unsplash.