The Stodmarsh moratorium holding up 40,000 homes across East Kent

It will take “a very large financial number” to fix the Stodmarsh phosporus & nitrogen issue, say Natural England in a meeting held on Wednesday 2nd December, 2020, between 09:30 and midday.

The Stodmarsh reserve (just outside Canterbury), is owned by Natural England and managed for wildlife and visitors. It covers a square mile of internationally-important reed beds, fens, ditches, wet grassland and open water, which provide an ideal habitat for breeding and wintering birds, invertebrates and rare plants. This site is especially important for bittern, marsh harriers and the shining ramshorn snail, which are rare across Europe; as well as water voles, which are rare in England. In late February, early March of this year, evidence of Beavers were seen at the Stodmarsh Nature Reserve. The reserve falls within The Stour catchment area which stretches 1,200 square kilomentres and is one of the most important water bodies for aquatic-dependent wildlife in the United Kingdom, according to Natural England.

27 representatives, representing fourteen different organization: The Planning Advisory Service, DEFRA, MHCLG, Natural England, Southern Water, Environment Agency and Heads of Planning from Ashford, Canterbury, Dover, Folkestone & Hythe, Maidstone and Thanet Council huddled together in yet another Zoom Meeting, to find solutions to the Stodmarsh phosphorus and nitrogen issue affecting the whole of the Stour region (pictured above).

At present there is a “moratorium” in place  for planning consent for development in the Stour region. This is due to the Stodmarsh phosphorus and nitrogen issue. An investigation is underway to discover mitigation strategies but will not conclude until March 2022.

At present “this is a “technical” and “planning” problem with little visibility in the public domain.”

The investigation underway (“WINEP”) will provide more data on how the Stodmarsh catchment area works. The data is expected in March 2022. It’ll provide important information, including firming up the way the catchments work (which will provide more certainty) but it is only a report. It will not change anything. It will provide facts that inform a subsequent options appraisal.

But nonetheless, the investigation underway will allow Natural England to translate a complex picture into something easier to communicate, “a very large financial number”, to fix the Stodmarsh phosporus & nitrogen issue

They have just “missed the bus” to get an upgrade for a Water Waste Treatment Works (WWTW), so the business as usual approach would see projects assessed in 2024 for delivery over 2025/30. The Stodmarsh phosphorus and nitrogen issue could easily rumble on until 2030 when a possible upgrade to WWTW could come on line.

It’s the interim period of 2021-30, without a new WWTW, that is difficult. There is potential for unforeseen consequences and unfortunate trade-offs. In general, on-site solutions, private water treatment, are not acceptable as they don’t perform as well as public infrastructure, plus some of the benefit is undone later in the treatment process.

Developers will need to demonstrate, either that their proposals will not have a significant effect on the Stodmarsh sites, or that mitigation measures can be delivered on-site, or secured off-site, to avoid any ongoing impact.

Developers no more like uncertainty than the next company. But how do you build across this large area when water courses  have been known to be polluted since 2009; and becoming more polluted, and do it so it’s negates any phosphorus and nitrogen escaping into the Stour region and affecting Stodmarsh?

Developers are wary of extra costs as it’ll eat into their potential profits. They could easily find other locations outside of East Kent to build where there is extra capacity and the phosphorus & nitrogen issue doesn’t exist. However this would have a knock on effect for all councils as they might not met their housing targets. A tricky problem indeed.

The Stour, which is the watercourse affected region, runs its varied course in the east of the county of Kent. It is an unusually complex stream, it rises as three parts; the Upper Great (Lenham) and East (Postling) forming the Great Stour at Ashford, when the Little Stour joins the main flow it becomes the Stour in Canterbury, which then splits into two again. The River Wantsum meeting the sea at Reculver, whilst the River Stour flows to the east and into the English Channel at Pegwell Bay.

Now this story is not just about saving some Schedule 1 birds, like the little owl, or common kingfisher, both common on the Stodmarsh protected area.

It’s about the eutropification of the water on the Stodmarsh site (which means it is being deoxygenated by algae). This is a symptom of overdevelopment causing worrying pollution in the whole catchment area.

What’s the causes of eutropification? Water pollution measurements look at nitrates, phosphorus and biochemical oxygen demand (BOD), this is the amount of dissolved oxygen needed to remove waste organic matter in the water. Some of this pollution comes from agricultural run-offs into surface water, most of it comes from the discharges of waste water works.

Back in April of this year, this was a subject of investigation by Panorama (still available on iPlayer), which identifies just how lax UK regulations are on these discharges.

The 2009 DEFRA & Envinornment Agency River Basin Management Plan evidences the Great Stour had historically high levels of phosphates and nitrogen pollutants. At page 8 of the plan, it makes it clear the South East River Basin, which include the Stour region, has some of the highest levels of personal water use in the country, whilst, on average, the amount of water available per person is less than for Morocco or Egypt.

The Stour region relies on groundwater for 72 per cent of its public water supply – more than any other.

In 2017, KCC published the Kent Water for Sustainable Growth Study, produced by AECOM. Again this report reiterated and evidenced how high phosphorus & nitrogen concentrations had impacted the biological quality of the water body, specifically on the fish populations, which the common Kingfisher and other wildlife depend.

These two reports already showed we were already in a bad place. Yet those responsible continued to allow new dwellings built, but did little to resolve a known identified problem.

The failure to act sooner when evidence was known, has lead to the position that every planning application in the Stour region affecting Ashford, Canterbury, Dover, Folkestone & Hythe and Maidstone, now has to fit with the detailed water resilience plans specific to the Stour region catchment and treatment area.

With so much land bought up, or earmarked by developers, running near, or next to the Stour:  Otterpool (East Stour), Mountfield Park (Stour), and Conningbrook Park (Great Stour), developers find themselves in the unenviable position of not being able to build out these new developments unless they are phosphorus and nitrogen neutral.

Area affected by Stodmarsh in the Folkestone & Hythe District

A developer’s profit on a new build 3 bedroom home in East Kent is about £70,000. Given we know there are 40,000 homes affected, we know the potential estimated losses to developers are in the region of £2.8 billion.

This is why developers are so worried. And no doubt so are the coffers of the national and local Conservative associations. Developer donations to political parties are very important indeed.

At the meeting it was spelt out in broad terms, Ashford & Canterbury Council are looking to build 25,000 dwellings between them. Then there’s up to 10,000 dwellings at Otterpool, plus approx 5,000 in windfalls, making a total of 40,000. Of course, this does not include what’s coming forward for Dover, Thanet or Maidstone Councils who fall within the Stour catchment area.

The nitrogen neutrality issue is not a new issue. But Stodmarsh is not just a nitrogen issue. It IS a phosphorus and nitrogen issue.

The Stodmarsh phosphorus & nitrogen is a complicated problem with fourteen organization involved to find a solution. It’ll require further steps to understand the component parts of this complex issue before any business case (or similar) can be presented, for action.

In any case it must be explained why action is necessary along all parts of the Stour. It must also set out a “Value for Money VfM” proposal – to show the whole cycle of –

investigating the problem properly

understanding and evaluating options (both short and long term)

explaining where the money is coming from

then showing how the result provides VfM.

It’s clear in the two and half hours huddled together in yet another Zoom Meeting, those present certainly did start on a road to finding solutions to fix this complex issue which affects developers, the Stodmarsh reserve and the East Kent river environment alike.

The Shepway Vox Team

The Velvet Voice of Dissent

About shepwayvox (1820 Articles)
Our sole motive is to inform the residents of Shepway - and beyond -as to that which is done in their name. email:

5 Comments on The Stodmarsh moratorium holding up 40,000 homes across East Kent

  1. This won’t affect the Folkestone and Hythe Council area because nothing affects the Folkestone and Hythe Council area, or if it does affect the Folkestone and Hythe Council area, then it still won’t affect the Folkestone and Hythe Council area, because the Folkestone and Hythe Council will say it won’t.

    So be calm and watch out for the formations of flying pigs doing aerobatics at the Shepway Airshow this year.

    • The Hersden developments, (immediately above the slopes leading down to the Western edge of the reserve) are underway. In addition the nearby Broad Oak/Sturry developments are using ‘SuDS’ to manage water run offs and these will inevitably discharge into the Stour when rains are high, (n.b. ‘flash’ rains are already increasing, as predicted, due to Climate Change). So, sadly, I’m not sure how much of a hold-up there is in practical terms.

      Plus, all this when it is known that the UK Gov algorithms that calculated the numbers of houses required around Canterbury is fundamentally flawed and has significantly overestimated future demand.

      Those political ‘donations’ are the only logical explanation.

  2. MR GD COX // July 11, 2021 at 09:49 // Reply

    Well done, putting this together.

    There is a related issue of developers on smaller sites affecting consultants reports, for the latter can depend on developer inputs. For example; destroy flora, put in application stating no flora on site and have consultants write a clearing nitrogen / phosphorus report on that basis. Hothfield Parish Council has pointed this out and that has ben one of two grounds for refusal. Of course, it may yet go to appeal.

  3. bubbles Parr // July 12, 2021 at 12:03 // Reply

    Farmers need to look what they are using on their fields I’m afraid ,as it does run off into the stream and water courses .

  4. Very good summary of the problems facing the Stour Catchment and the Stodmarsh National Nature Reserve (NNR).

    The Stour at Canterbury is supposedly a Chalk River. It is true that the water is often sparkingly clear and clean, but it is often very murky and smelly, and I wonder how much of the flow is reliant on treated sewage from the Ashford WWTW?

Leave a Reply

%d bloggers like this: