Pollution: Welsh Housing Sites at a Standstill

After extremely high phosphate levels were found in rivers across Wales, the latest figures from the Community Housing Cymru (CHC) highlighted that nine housing associations had been impacted negatively since 2022.

A total of 28 affordable housing sites are now at a standstill, meaning over 1,000 affordable housing developments aren’t going to be delivered on time, exacerbating the housing crisis issue in Wales.

In January 2020, Natural Resources Wales (NRW) set stricter targets for phosphate levels for all rivers that are Special Areas of Conservation (SAC) across Wales. This was tightened further in January 2021.

The review followed evidence from the Joint Nature Conservation Committee that warmer and drier weather, predicted as a result of climate change, could reduce river flows during the summer and therefore increase phosphate concentrations. It is also based on new evidence about the damaging effects of phosphates on water ecosystems and species.

Tighter pollution compliance targets hindering housebuilding across Wales

The CHC explained: “At present, over 60% of waterbodies in Wales fail against the tighter targets, and Welsh local planning authorities are being asked to take more action to avoid further deterioration of the environment. It means any proposals for development within SAC river catchments - in particular, those that will generate increased volume or concentration of wastewater - must now prove that the design will not contribute to increased phosphate levels.”

Phosphates are nutrients that occur naturally in low levels and are necessary for the healthy functioning of rivers, but increased impacts of climate change have caused higher levels which are damaging to wildlife as they lead to a growth in algae.

The disruption, spanning months, has deterred housebuilders from considering sites close to the affected areas, which can cause issues to the pipeline of affordable housing delivery in the future.

One Welsh association expressed concerns that nearly 400 homes cannot enter planning stages due to the phosphate issue.

Laura Courtney, Head of Policy and External Affairs at CHC, said: “More than ever, the people of Wales need highquality, safe and affordable homes. If we are going to address the Welsh housing crisis, we need to build more social homes across the whole country.

Balancing the needs of the public and the planet proving difficult

“Delays to development in the areas affected by this issue impacts not only those that are in need of social housing but the communities that housing associations work hard to support. This is why we have been pushing for short and long-term solutions that protect the environment while allowing houses to be built.”

In order to help developers determine whether phosphate levels are safe in specific areas, the CHC launched a nutrient budget calculator.

They explained: “This tool enables you to calculate the phosphate levels that a proposed residential development in Carmarthenshire could produce. This is an important first step in allowing nutrientneutral development to proceed and is the first of its kind launched in Wales.”

This is a free resource designed specifically for Carmarthenshire; it will support developers in understanding the impact of development and will allow them to confirm the proposed development’s phosphate budget and consider mitigations.

Nutrient budget calculator to support housebuilders and developers

The CHC noted: “Although it is not required that you use this calculator, we strongly encourage you to do so. Any applications submitted using alternative calculators will be subject to additional scrutiny to determine their relevance to conditions in Carmarthenshire.”

Various methods to reduce levels of phosphate in rivers have been deployed, with varying levels of success. The most common practice is to add chemicals, such as ferric sulphate, to sewage to reduce phosphate levels at the beginning of any processing.

Despite reduced levels of phosphate at the earliest stage possible, there are concerns that the cost of these chemicals will rise in the future, and they can also lead to an increase in iron levels, which itself may need to be addressed, making it less viable as a long-term option.

Another option is sand filtration; while still relying on the addition of chemicals to waste, vertical sand filters can easily remove the phosphates.

Again, this comes with significant time and cost restraints for the housing sector, while they aim to improve time and cost efficiencies as budgets continue to shrink.