A law requiring new homes not to pollute nearby wetlands, rivers and nature reserves has halted development in part of England.
Forty-two local authorities in England were told last month they must ensure new homes are “nutrient neutral” and no harmful nitrates or phosphates into river basins and protected areas, including Cumbria’s Eden Valley, Cornwall’s River Camel and the Norfolk Broads.
In these areas — near protected areas like Special Areas of Conservation (SACs) — planning authorities are unable to approve new applications for any type of home until developers prove they aren’t contributing to nutrient pollution.
Natural England, the government’s conservation agency, has already required developers in 32 local authorities to prove they are not causing additional pollution to protected areas, following a 2018 Court of Justice ruling protecting EU-designated nature reserves.
Nutrient pollution causes algal blooms that deplete oxygen in the water, killing fish and harming other aquatic life. Agriculture is the primary cause of excess nutrients being flushed into rivers and wetlands, along with discharges from overburdened sewage treatment plants, but stormwater runoff from roads and new developments can also contribute to pollution.
The Home Builders Federation estimates up to 120,000 new homes have been delayed due to “nutrient neutrality rules” in 74 local authority areas, with 42,000 new homes delayed in Greater Norwich alone.
Some areas, like the Solent, have introduced mitigation measures where developers can buy nitrate credits from landowners, including environmental organizations, who use the money to rewild farms or create pollution-absorbing wetlands in the catchment.
But many local governments are complaining that they have not received adequate advance notice to allow new developments to proceed and are therefore unable to meet their mandatory new housing targets. Norfolk has no mitigation plans yet as all development has been halted without full planning permission in the Broads and River Wensum catchments, both of which have harmful nutrient loads.
The government’s call for “nitrate neutrality” was welcomed by Rosie Pearson, chair of the Community Planning Alliance, a grassroots campaigning group for sustainable development.
“It’s great to see and a rare example of where the public protection system is doing what it should,” she said. “But with councils bound by their five-year targets for housing supply and a government agency saying ‘build, build, build’ and then Natural England and Defra go, ‘you can’t build, you’re harming the environment’ . it’s a complete mess.”
Reducing nutrient loads by creating new wetlands was “a band-aid,” according to Pearson. “All these wetlands are being created that are going to be great for nature, but the government keeps ignoring the underlying problem, which is the sewage system.”
Homebuilders warn the measures could cost developers up to £5,000 per house and delay affordable houses and social housing. A study in Somerset found that the urban environment contributes 4% to nutrient pollution, with the vast majority coming from agriculture and sewage discharges.
James Stevens, director for cities at the Home Builders Federation, said: “Developing a consistent and standardized approach to mitigating water neutrality is essential to removing the growing blockage to the home supply.
“We call on the government to agree without delay on appropriate measures that reflect the contribution of housing provision to this problem. The situation has been going on for a number of years and it is imperative that solutions are urgently agreed and implemented.”
In the Solent, where nutrient neutrality rules were introduced in 2018, it took 18 months to set up mitigation sites but Natural England said it would be much quicker for the 42 new local authorities as there was a nutrient calculator and £100,000 of funding to help councils and developers find solutions.
In South Hampshire, nutrient credits bought by developers have enabled the construction of more than 3,000 ‘nutrient neutral’ new homes.
The Hampshire & Isle of Wight Wildlife Trust (HIWWT) used credits to purchase two farms with a total area of 450 hectares in the Solent catchment, restoration of heavily fertilized land that caused nutrient pollution, restoration of biodiversity, and removal of 25% more nitrates than the assigned credits.
“It works,” said Debbie Tann, executive director of HIWWT. “That means development is able to mitigate its impact, but it’s really important to recognize that the pollution in the Solent is terrible and that alone won’t eliminate it. What we really need to address is agriculture, fertilizer reduction and water companies need to address sanitation.
“This is a good step by Natural England but we need Government to move forward on the other issues as well.”
Melanie Hughes, director of sustainable development at Natural England, said all protected wetlands affected were in an “unfavorable state” due to nutrient pollution such as: B. fetid mats of algae that cover salt marshes in the Solent, which prevent waders from feeding in the mud.
“We can’t keep polluting these areas — that’s the line that’s been drawn,” she said. “We’re excited to use nature-based solutions to solve the problem, which have broader benefits.”