Creating new nature reserves, retrofitting social housing and growing particular species of grass will all be used to unlock thousands of new homes across Somerset.

More than 18,000 new homes across the county have been held up by the phosphates crisis, with developers having to secure additional mitigation to prevent any net increase in phosphates on the Somerset Levels and Moors.

Somerset Council was awarded £9.6m from the Department for Levelling Up, Housing and Communities (DLUHC) shortly before Christmas 2023, to be spent on a number of solutions to ease the crisis and deliver much-needed new housing.

The council has now laid out exactly where the funding will be spent over the next two years to end the logjam of planning applications.

Here's everything you need to know:

What is the phosphates crisis?

Phosphates are commonly found in a variety of forms in Somerset, ranging from agricultural fertiliser to human and animal urine and faeces.

If phosphates are present in too high a concentration in watercourses, they can cause eutrophication, where growing blooms of algae takes oxygen out of the water and harming native species of fish and other wildlife.

The Somerset Levels and Moors are a Ramsar site, meaning they are protected under international law against any form of environmental pollution, including eutrophication.

Following the Dutch N court case, Natural England issued legal advice in August 2020 to Somerset's local authorities, stating that no development of any kind could be approved within the Somerset Levels and Moors catchment area without additional phosphate mitigation being secured.

Since then, planning officers and developers have been working to find short-term solutions to prevent any net increase in phosphates from new homes or commercial premises that are wishing to be constructed.

These solutions have included:

• Creating new wetlands, which can filter out and absorb phosphates (such as at the Staplegrove urban extension in Taunton)
• Fallowing agricultural land, taking it out of active production (such as the Canal Way development in Ilminster)
• Upgrading waste water treatment plants, removing phosphates from sewage (such as at the Lowerside Lane site in Glastonbury)

What are phosphate credits – and how well are they working so far?

Three main rivers flow into the Somerset Levels and Moors Ramsar site (which is protected by international law) – the River Brue (which runs from Bruton to Highbridge), the River Parrett (which runs from Cheddinton in west Dorset to Burnham-on-Sea) and the River Tone (which runs from the Brendon Hills to its confluence with the Parrett at Burrowbridge).

Numerous phosphate credit schemes were put in place for the different catchment areas by the former district councils, which have now been inherited by Somerset Council.

Phosphate credits are created by measures taken by the council to offset the impact of existing housing – such as retrofitting social housing, or any of the other forms of mitigation previously listed.

Developers can purchase credits from third parties to pay for off-site phosphate mitigation – for instance, taking agricultural land out of use upstream of a new housing development.

In the River Brue catchment area, 16 major planning applications comprising around 800 new homes are currently being held up.

To get around this, two phosphate credit schemes have been implemented by fallowing land at two farms in the former Mendip area – Yew Tree Farm near Wraxall (which has unlocked 504 new homes) and Manor Farm in Prestleigh (which could unlock up to 1,400 new homes).

In the River Parrett catchment area, there are around 4,500 homes currently being held up, the majority of which lie in the former South Somerset area.

The council's planning committee south has been steadily working through a backlog of major applications, approving 765 homes with a variety of phosphate solutions, such as replacing septic tanks with package treatment plants and fallowing land within the Blackdown Hills.

Of these 765 homes, 435 had already been approved by councillors before August 2020, with the applicants having to come back for re-approval after mitigation had been agreed.

A further 185 homes with mitigation, on Tintinhull Road in Yeovil, were approved before South Somerset District Council before its abolition in April 2023 – but the legal agreements between the council and developer have not yet been signed, meaning construction cannot yet begin.

In the River Tone catchment area, there are currently 111 planning applications which are "awaiting a phosphate solution" – equating to around 2,600 dwellings, with the majority being in the former Somerset West and Taunton area.

Somerset West and Taunton Council set up its own phosphate credits scheme in July 2022, which has been focussing on unlocking smaller developments to take the pressure of smaller house-builders.

On the larger development sites, such as Orchard Grove in Taunton, officers are working with developers to see what solutions can be delivered on site.

What about the River Axe?

A small section of Somerset – including Chard and the neighbouring villages fall into the catchment area of the River Axe which reaches the sea at Axmouth in east Devon and is also subject to additional mitigation needs.

This catchment includes large sections of the Chard eastern development area (CEDA) and a recently approved development of 95 homes on the B3167 Perry Street in South Chard (near Tatworth).

Somerset Council, Dorset Council and East Devon District Council are currently working on a separate bid for nutrient mitigation funding from DLUHC, which will be submitted by April 26.

The other River Axe which flows through Somerset – which runs from the Mendip Hills to the Bristol Channel – is outside of the Levels and Moors Ramsar site and is therefore not affected by the phosphates crisis.

What will be done next to ease the crisis?

The full strategy for tackling the phosphate crisis, on top of the credits schemes already in place, was published before the council's strategic planning committee met in Taunton on Thursday morning (March 21).

The £9.6m provided by the government – of which only £500,000 has currently been paid to the council – will be divided between six different projects designed to unlock the remaining homes within the Somerset Levels and Moors catchment area.

The six projects are as follows:

1. Salinity Solutions pilot:  the council has been working with Birmingham-based firm Salinity Solutions Ltd. and Wessex Water, developing modular units which can be attached to existing water infrastructure. Using the principle of reverse osmosis, the units can filter out 95 per cent of water-borne phosphates before they reach the Levels. Following initial trials in July 2023, this pilot scheme will run for six months, unlocking large numbers of new homes before more permanent solutions are implemented.  PROJECT BUDGET: £2m
2. Call for sites for land or nature-based solutions: working with the Farming and Wildlife Advisory Group (FWAG), the council will seek to identify land within the Levels and Moors catchment area where new wetlands or other natural mitigation can be delivered. Any identified sites will gradually be delivered to support large-scale developments, and may contribute to biodiversity net gain which is now required under new planning laws.  PROJECT BUDGET: £3.5m
3. Retrofitting social housing: the council has been working with social housing providers (such as LiveWest and Stonewater) to retrofit existing social housing, reducing the amount of phosphates which enter the Levels and Moors from current properties. This includes replacing older septic tanks, which are more efficient and can remove larger quantities for phosphates from effluent. PROJECT BUDGET: £1m
4. Nature-based solutions on council-owned land: the council has been reviewing its land and property portfolio has part of its budget setting process, identifying numerous parcels of land which could be sold off to generate funding for local services. As part of this ongoing review, officers will look at whether publicly owned land can be used to deliver phosphate solutions (e.g. turning underutilised green space into new wetlands or nature reserves). PROJECT BUDGET: £2m
5. Miscanthus grass pilot: Miscanthus grass, also known as elephant grass, is a bioenergy crop which can absorb relatively large quantities of phosphates from the soil. Working with the Taunton-based Miscanthus Nursery, the council will look at growing miscanthus on fallowed land to generate additional phosphate credits (while providing an income for farmers). PROJECT BUDGET: £640,000
6. New technical innovations: the remaining government funding will be used for research and development, looking at emerging technologies which could be scaled up and deliver additional mitigation in the years ahead. PROJECT BUDGET: £480,000

Do these improvements go far enough?

Councillor Henry Hobhouse (whose Castle Cary division has seen significant housing growth over the last decade) welcomed the investment, but said more needed to be done by Wessex Water to ease the crisis.

He said: "Wessex Water has a restriction on their capital expenditure, but they have no restriction on their hiring expenditure.

"They can hire in their sulphate dosing equipment across their 84 sewage plants which are failing their tests at the moment. Why haven't we talked to Wessex Water about doing this?"

Matt Wealdon, Wessex Water's director of infrastructure development, responded that it was not possible for his company to accept any further government funding without reducing income for other services.

He said: "While the council may pay us to do something, we have a revenue cap – so we would have to reduce income from somewhere else.

"What we'd all like is to receive this kind of funding outside of the revenue cap, but that is the financial arrangements under which we currently have to operate.

"We did offer this to Rebecca Pow [Defra minister and Taunton Deane MP] in May 2022 and we had no response.

"What is needs is Ofwat to approve that the income from the council can come in outside of our revenue cap.

"We are already removing far more phosphorus from our planned works than any that is going to be added by new properties.

"Our upgrade plans is already stacked out, and our ability to do more in our supply chain is very limited."

Under its new business plan, Wessex Water is planning to spend £900m between 2025 and 2030 on "nutrient reduction" upgrades, with a further £100m being spent on improvement capacity at its waste water treatment plants.

Turning to the use of miscanthus, Mr Hobouse added: "Can we please add willow and reed to this? Both of these are known to grown on the Levels and all of them remove phosphates from the soil,

"How are we intending to use the material when we cut it and remove it from the site? Are we going to use it for heating or other energy generation?"

Alison Blom-Cooper, the council's chief planning officer, replied: "The miscanthus trial is just to demonstrate its efficacy.

"Natural England is already happy with willow and other native species for phosphate mitigations – we don't need to trial them, they will be part of the call for sites.

"Miscanthus is already used for biofuel and there is a huge opportunity for carbon capture. Miscanthus Nursery is also developing its use for recyclable packaging and insulation blocks."

What happens next?

Following the committee's approval of the phosphates strategy, the numerous new trials and projects will be implemented over the next 18 months.

Further reports on the progress of each project will come back before the strategic planning committee as the situation developments.

The High Court will shortly publish its ruling on a landmark phosphate mitigation case relating to the Jurston Fields development in Wellington, following hearings on Tuesday and Wednesday (March 19 and 20).