Tens of thousands of new-build homes in England have been placed on hold due to a law protecting wetlands.
Forty-two local authorities were last month told they must ensure that new homes are “nutrient neutral” and do not add damaging nitrates or phosphates to the soil in parts of the UK..
In these areas, planning permission will not be granted unless developers can prove they are not adding to nutrient pollution.
Natural England, the government’s conservation watchdog, has already required developers in 32 local authorities to demonstrate they are causing no additional pollution of protected sites after a 2018 court of justice ruling to protect conservation areas designated by the EU.
Nutrient pollution causes algal blooms that deplete oxygen in the water, killing fish and harming aquatic life.
But local councils say they have not been given adequate notice to enable new developments to continue.
The Home Builders Federation estimates that up to 120,000 new homes have been delayed because of the rules in 74 local authority areas, with 42,000 new homes delayed in greater Norwich alone.
Most areas have issued a blanket ban on developments in affected areas until the ruling is lifted - a move that threatens to derail Boris Johnson's election pledge to build 300,000 new houses a year.
Rosie Pearson, the chair of the Community Planning Alliance, said: “It’s great to see and a rare example of where the public protective system is doing what it should.
“But with councils bound by their five-year housing supply targets and one government department saying: ‘Build, build, build,’ and then Natural England and Defra going: ‘You can’t build, you’re harming the environment,’ it is a complete mess.
“All these wetlands will be created that will be great for nature but the government constantly ignores the underlying problem, which is the sewage system.”
Housebuilders are warning the measures could cost developers up to £5,000 per home and affordable homes and council houses will be delayed.
James Stevens, the director for cities at the Home Builders Federation, said: “Developing a consistent and standardised mitigation approach on water neutrality is essential to removing the growing block it is causing to housing supply.
“We are urging government to agree proportionate measures that reflect the contribution of housing delivery to the issue without delay. The situation has already been ongoing for some years and it is imperative that solutions are agreed and implemented urgently.”
Melanie Hughes, the director of sustainable development at Natural England, said all of the affected protected wetland sites were in “unfavourable condition” because of nutrient pollution.
“We can’t carry on polluting in these areas – that’s the line that’s been drawn,” she said.
“We’re pleased that we’re using nature-based solutions to help resolve the problem, which have much wider benefits.”
A government spokesperson said: “We want to protect the environment and deal with the build-up of nutrient pollution whilst building the homes this country needs.
“While house building is not the primary cause of nutrient build up, we want to introduce measures quickly to allow development to move forward.”
