Phosphates threaten thousands of new homes across Somerset

By Ellen Nicholson

On 17 August 2020, Natural England issued a letter to all Local Planning Authorities (LPAs) in Somerset regarding the high levels of phosphates in the Somerset Levels and Moors.

The Somerset Levels and Moors are ‘Special Protected Areas’ (SPAs) under the Ramsar Convention and have been suffering from excessive phosphate levels in recent years, as a result of new housing and farming practices involved phosphate leaching. In adding phosphates to the watercourses draining to the SPAs, such development causes eutrophication, a phenomenon involving excessive algae growth which in turn damages natural habitats. New housing adds to this problem as waste water arising from everyday activities almost inevitably contains phosphorous.

In light of a recent Court Judgement (known as Dutch N), Natural England advised LPAs that before determining a planning application that may give rise to additional phosphates within the catchment, they should undertake a Habitats Regulations Assessment (HRA) to determine the likely impact on the SPAs. Applicants now need to demonstrate that their proposals are ‘nutrient neutral’, i.e. that they will not lead to an increase in levels of nutrients such as nitrates and phosphates. This requires a calculation of the likely nutrient load and a solution to be found that will provide mitigation initially for the short-term, prior to the upgrading of Waste Water Treatment Works, but ultimately in the long-term to provide mitigation for a period of 80-125 years.

The types of development that will be subject of a HRA include:

  • New residential units – including tourist accommodation, gypsy sites /pitches
  • Commercial developments – where overnight accommodation is provided
  • Agricultural Development – additional barns, slurry stores etc. where it is likely to lead to an increase in herd size
  • Prior Notifications of agricultural development where, as a result of the development, the herd size may increase. Also, prior notifications for change of use of office to dwellings and agricultural buildings to dwellings
  • Anaerobic Digesters
  • Possibly some tourism attractions

The announcement threatens to severely delay and/or increase mitigation costs for all current and forthcoming applications for these types of developments within the catchment of the SPAs. This is a huge area of Somerset, taking in significant growth areas including Taunton, Bridgwater, Glastonbury and Yeovil and halting the determination of applications that could deliver over 11,000 new homes.

Since receiving Natural England’s letter, the four Somerset Districts Councils and Somerset County Council have been working hard to minimise delay and uncertainty around planning applications, following recent guidance over unacceptable amounts of phosphates in the Somerset Levels and Moors. This work includes a county-wide nutrient strategy to identify both short term solutions to help clear the current backlog of planning permissions and longer-term solutions to address the existing and future growth commitments. The Councils have also written to Central Government seeking support including:

  • A commitment that current infrastructure and affordable housing funding programmes will not be placed at risk by the phosphates issue and that extensions to spend programmes will be permitted where necessary
  • Additional revenue and capital funding be made available to implement the identified measures in the Somerset Nutrient Strategy and unlock the delivery of 11,000 new homes in Somerset
  • A commitment that relevant Government regulators (OFWAT, Environment Agency and Natural England) will be addressing the major contributory polluters responsible for the discharge of nutrients into the water courses that feed into the protected sites in England

Rapid increase in the supply of nature-based projects. The most effective projects for the long term involve the digging of wetlands, however these can take a number of seasons to establish. Short-term mitigation

The first stage of this work is now complete with the creation of a phosphate budget calculator. This can be used by applicants to assess how much phosphate will be generated by a development and how much will need to be offset to achieve nitrate neutrality. Somerset West and Taunton Council used funding from Homes England to lead the joint commissioning of consultants Royal Haskonings to prepare the calculator which has been signed off by Natural England. It will provide a standardised and transparent decision-making tool for the Local Planning Authority and Developers.

A planning application will only be able to proceed to a positive recommendation if the proposed development is phosphate neutral or there is identified mitigation that can be secured. The calculator will remain under constant review and updated to ensure that it reflects any data changes. The calculator will also be updated in due course to take into account planned upgrades to Waste Water Treatment Works within Somerset by Wessex Water.

This is however just one step of a much longer process for dealing with the issue. There is still much to be agreed in terms of offsetting solutions and the availability of nature-based projects that developers can potentially purchase (directly or by buying credits) to discharge their environmental obligations. The EnTrade Catchment Market proposal will work by allowing the LPA to issue planning permission, with a requirement on the developer to achieve a level of nutrient offset, that can be met by redeeming credits from the Catchment Market prior to occupation of the planned development. This will be done through either a Grampian Condition or s106 agreement. However in this proposal, should EnTrade fail to provide the required amount of mitigation to the satisfaction of the local authority, it will be the developer that will lose cash and time. At this stage it is unclear if sufficient credits will be available, and fairly available, to address the needs of housebuilders. It is extremely likely that volume housebuilders will be best placed to acquire these credits over small and medium sized developers.

For this reason, it is vital that the four Councils progress their own strategic solutions so there will be enough alternative projects to help developers meet their obligations. The Housebuilders Federation has suggested the following needs to be produced in order to deliver an effective strategy:

Short Term (now to 6 months)

  • Delineation of the precise catchment areas through the production of up-to-date maps that reflect where waste-water treatment plant upgrades  are planned, so that this programme is reflected in the national calculator.
  • Rapid increase in the supply of nature-based projects. The most effective projects for the long term involve the digging of wetlands, however these can take a number of seasons to establish. Short-term mitigation measures include the fallowing of land and returning existing grazing land to meadow which are quicker to establish but much less effective in reducing nutrients. Increasing the supply of nature-based projects will require encouraging farmers to switch land from agricultural use to these nature-based projects.
  • LPAs need to work together to provide a credit facility that developers can transparently buy-into at fixed rates per unit (to allow new residential schemes to proceed) then oversee the future provision of wetlands or other mitigation on offsite land yet to be secured or delivered for that purpose. This will not require the mitigation to be complete for purchasers to occupy plots, thereby easing the current blockage. This would obviously require Natural England to take a pragmatic view on delivery of mitigation.

Medium term (within one year)

  • LPAs should devise a strategy for the supply of nature-based solutions in the long-term by utilising land in its ownership/control. This would be similar to the SANGS approach adopted in Surrey, with defined financial contributions to provide mitigation that can be operational by the time plots need to be occupied by the public.

Long-term (within 2-5 years)

  • All waste-water treatment plants not currently planned for an upgrade should be upgraded rapidly to filter-out any nutrients to prevent leaching into protected wetland areas. However, this may not remove the need for scheme-specific mitigation so it will be necessary to avoid the possibility of developers paying twice for offsite mitigation as well as water companies increasing their infrastructure costs to cover future upgrading of Waste Water Treatment Works.

As evidenced above there is still much work to be done. The delay in determining applications will of course have a huge impact on LPA’s five-year housing land supply. Having attended a number of events on this topic there is still much uncertainty for both developers and local planning authorities. There is an acute need for more work and investment to devise a long-term strategy for dealing with this issue, and to bring forward the much needed homes for Somerset.

The calculator is available on individual Council’s websites as follows:

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