The UK government’s plan to lift restrictions on housebuilders in England that are designed to mitigate the river pollution caused by new homes has been criticised as the “easy way out” of having to solve a complicated problem and is likely to harm rivers, say experts. There are also fears it could reduce transparency around the effectiveness of anti-pollution measures.
New homes are a problem for rivers because their occupants increase the amount of pollution that is released into waterways, particularly phosphorus and nitrogen. These nutrients are expensive to process in wastewater treatment works and so a significant amount ends up being released into local rivers. This, in turn, leads to the deoxygenation of water bodies, harming both fish and plant life.
Many rivers in England are already polluted with nutrients. In 2017, nutrient neutrality rules were introduced, which force housebuilders in some English regions to have a neutral impact on pollution levels, such as by purchasing so-called nutrient credits designed to act as river pollution offsets.
These rules have been blamed for the hold-up of 140,000 new homes being built in England, says the Home Builders Federation in the UK, according to a survey of the trade association’s members. On 29 August, the UK government announced that it would scrap the regulations.
New Scientist has previously reported that the current nutrient pollution regime isn’t perfect and requires improvement, but experts warn that ditching it entirely is a backwards step and could ultimately lead to more polluted rivers in England.
“I think nutrient neutrality was on the edge of being made to work,” says Peter Powell at the Welsh Dee Trust, a charity that aims to protect the river Dee in Wales, where a form of nutrient neutrality rules will still apply because environmental policy is a devolved matter.
“But the [UK] government is just scrapping the regulation instead of putting the effort in to make it work,” says Powell. “It’s the easy way out.”
The new rules don’t mean nutrient credits will go completely. Housebuilders in nutrient neutrality areas in England will no longer need to pay for them mitigation efforts, according to the UK government. Instead, they will be funded by taxpayers.
Such an approach is unlikely to solve the wider issues with nutrient credits, says Powell, such as the practicalities involved and gaps in knowledge surrounding how effective the measures are. One scientifically backed alternative for reducing nutrient pollution is to build wetlands besides sewage treatment plants, he says. These process treated sewage and can store nutrients for hundreds of years, but few have been built in England as it has been difficult to find and purchase land near sewage treatment works, says Powell.
Moreover, long-term monitoring is required to determine if they are working effectively, which is expensive. The UK government says it is doubling investment for nutrient mitigation to £280 million, funds that could be used to build these wetlands, but it is unclear if this will be enough to make this idea work, says Powell.
“It takes time to build these wetlands and I don’t think the government will be able to move fast enough,” he says, adding that he is concerned that it is unclear if money will be provided for the maintenance and monitoring of these wetlands in the long term. “I think these new plans will make rivers more polluted,” says Powell.
A spokesperson for the Department for Levelling Up, Housing and Communities (LUHC) says these worries are unfounded. “The government is committing to compensate for any [nutrient] pollution from developments,” says the spokesperson. “We’ll do this in a number of ways, such as through the creation of the new protected site strategies that identify evidence-based local solutions to improve water quality.”
The UK government says 100,000 houses will be built in the next six years as a result of scrapping nutrient neutrality rules. Plans include telling local authorities to not consider nutrient pollution when judging planning permission for new houses.
Peter Cruddas at the University of Portsmouth, UK, says such moves could take calculations about the effectiveness of nutrient mitigation efforts behind closed doors. The current system requires councils and developers to be relatively transparent, he says. “It seems the government will just be doing some environmental initiatives and we all trust they balance out,” he says.
LUHC says more information will be released in due course about how such calculations will be made.
On the plus side, Cruddas says that a taxpayer-funded scheme could lead to a more strategic use of nutrient pollution mitigation methods rather than the piecemeal approach employed today.
Kate Russell at Tellus Natural Capital, an environmental consultancy, says she fears this policy reversal could make it harder to encourage other nature-based market solutions, such as carbon credits.
“If the government can do a policy U-turn on this, then the investors who are interested in biodiversity or carbon or flood mitigation will take a pause and say well, they can do a U-turn on the other measures too,” she says. “It could have a chilling effect.”
The UK government denies this is the case. “I don’t think anything’s been said that would imply that,” says the LUHC spokesperson.