Land intended to offset 311 Ilminster homes being sold off

The council announced in July 2024 that it was intending to dispose of land at Manor Farm, on Water Lane in Seavington St. Mary, with around 50 acres being retained and the existing buildings being converted into up to seven homes.

Following the farm's closure, the council secured an agreement with Natural England to use the remaining land as phosphate mitigation to offset a planned development on Canal Way in Ilminster, brought forward by Persimmon Homes South West.

But in light of recent upgrades by Wessex Water, this mitigation is no longer needed - with the council now seeking to sell of the land to avoid incurring any financial loss.

Following the Dutch N court ruling, and the subsequent legal advice issued by Natural England in August 2020, additional mitigation has been required on any development within the Somerset Levels and Moors catchment area to prevent any net increase in phosphates.

Land originally intended to be fallowed (in blue) as part of the development on Canal Way in Ilminster (red)

Around 12,000 homes across Somerset are currently in limbo - though this has been slowly decreasing as a result of a recent ruling by the Supreme Court regarding the Jurston Fields development in Wellington.

The council's planning committee south granted outline permission in January 2024 for 360 homes on Canal Way in Ilminster - with phosphates from the new homes being offset by fallowing large amounts of council-owned agricultural land south of the town.

Following the closure of Manor Farm after the last tenant farmer retired, the council secured an agreement with Natural England to use the surplus farmland as phosphate credits, allowing new homes within the wider River Parrett catchment to be offset.

This arrangement was intended to remove the need for the land south of Ilminster to be fallowed, as well as providing the means of unlocking other housing developments across the former South Somerset area.

But since this agreement was finalised, Wessex Water has been upgrading its waste water treatment plants across Somerset to remove greater quantities of phosphates before they enter the protected part of the Levels and Moors.

As a result, the council is now seeking to sell off the phosphates credits to avoid incurring a potentially significant financial loss.

David Ashton, the council's lead surveyor for estate strategy and development, said: "Manor Farm was brought to the open market and is currently under offer, with completion anticipated in the next few weeks. Part of the holding has been retained and will continue to be let for farming purposes.

"As part of the restrictions on use of the former agricultural buildings and yard above, phosphate credits were reserved and retained by the council for potential alternative phosphate mitigation strategies on other council-owned land, if required.

"The phosphate credits are secured through restriction on use at Manor Farm, which prevent the farmstead from being used again for any purpose that would generate phosphates, including animal holding or manure storage.

"These phosphate credits are now no longer needed as an alternative phosphate mitigation' for the proposed development on council-owned land at Canal Way in Ilminster, and should be disposed as soon as possible, given their diminishing value due to ongoing waste water treatment upgrades."

Plans for 97 homes within the Canal Way site in Ilminster (Image: EDP)

The Canal Way site is expected to deliver a revised total of 311 homes across four phases - with Persimmon Homes publishing detailed plans for the first phase of 97 homes in mid-January.

Under the revised mitigation strategy, the new development will be "phosphate-neutral", with the homes being delivered through sustainable urban drainage measures and "phased fallowing" of land within the wider site.

The council has not provided a public estimate of the value of the phosphate credits, citing commercial sensitivity.

The council is expected to make a decision on Persimmon's plans for the first phase of the Canal way site before the end of the year.

Following recent changes to UK planning law, this decision is likely to be taken behind closed doors through the delegated powers of the council's planning officers; however, the plans could come before the planning committee south if the two Ilminster division members and its chairman deem it to be necessary.