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.