Stopping the dumping of sewage into rivers and the sea will require huge infrastructure spending and will probably push up water bills, according to a new House of Lords report.
Raw sewage discharge through storm overflows is meant to be an emergency last resort during heavy rain but the government says it happens too often.
The system “relies on releasing polluted water”, says the report.
It blames successive governments, regulator Ofwat, and water companies.
The root cause of the UK’s sewage problem is not contested: the system was designed and built by the Victorians and there simply hasn’t been enough investment in the drains and treatment plants needed to cope with a growing population and more intense storms.
That means raw sewage regularly being discharged with rainwater into rivers and onto beaches.
“For decades the focus has always been on supplying cheap good quality water to the population. The environmental objectives have not been focused on,” says Lord Cromwell, a member of the House of Lords Industry and Regulators Committee, which published the report.
“It is going to be hugely expensive to put this right.”
Most see the solution as building a waste water system that manages rainwater and waste water separately, so they no longer go to the same place to be treated.
But estimates for how much this updated sewage network might cost vary widely. The Lords report says they had heard estimates that range from tens of billions to hundreds of billions of pounds over decades.
Last year the government published its Storm Overflows Discharge Reduction Plan, which will it says will compel water companies to invest £56bn over the next 25 years.
That cost will almost certainly will be passed on to customers, with the Lords report saying there will need to be a “social tariff” for those unable to pay the higher rates. It did not say how much it expected bills to rise.
Responding to the report the Department for Environment Food and Rural Affairs (Defra) called the £56bn plan the “largest infrastructure programme” in the water companies’ history.
“We know that more needs to be done, which is why we will go further and faster to hold companies to account in delivering for customers and our environment,” a Defra spokesperson said.
The Lords report also called for the water regulator Ofwat to push for greater transparency from water companies. Despite rising public awareness, companies still don’t have to provide comprehensive information on what, when and how much they release.
At present they release data on how many hours their storm overflows are open each year. In 2021 that came to a grand total of more than 2.6 million hours in England. There is no routine monitoring of the volume of the outflow, its contents or the quality of most of the UK’s waterways.
In a statement Ofwat welcomed the Lords report calling it “helpful and detailed”. The regulator says it intends to do more to hold water companies to account, pointing out that it is currently investigating six companies.
Executive pay
Higher bills are likely to focus more attention on how much profit water companies make and how much their executives are paid.
Earlier this week Ofwat said water companies should “take account” of environmental performance when deciding whether to pay dividends. The peers are clearer, saying water company bosses should not receive large bonuses while their companies pollute and calling for “greater individual accountability (at water companies) and sanctions for egregious environmental crimes”.
In response to a BBC request for comment, trade body Water UK said it welcomed the committee’s recommendation that the government provide Ofwat with guidance on the increased level of investment needed to further improve environment and water security. It made no comment on the peers’ call for executive pay to be linked to environmental pollution.
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