Stodmarsh: What’s the solution?

30th November 2022

The city of Canterbury has always been praised for its historical heritage; yet like all cities, it has an eye to the future, with plans to develop major sites in the heart of its high street. However, environmental concerns at Stodmarsh Nature Reserve have halted all progress. Louis Walker investigates what’s stopping Canterbury from moving forward.

Concerns for our environment have reached greater awareness on a global scale from climate change to pollution but who focuses on what is happening locally?

Just thirty minutes outside of Canterbury city centre lies the internationally recognised Stodmarsh Nature Reserve. Boasting the largest reed bed in the Southeast of England as well as lakes and wetlands, the importance of the site to the rare wildlife it supports cannot be understated.

Despite being a site of special scientific interest, Stodmarsh’s lakes suffer from pollution due to the wastewater from the River Stour. A Natural England review in 2018 saw that the wastewater discharged into the River Stour catchment was raising nutrient levels and deteriorating the water quality at Stodmarsh.

These findings led Natural England to release advice in January 2020 to local planning authorities like Canterbury City Council. It stated that no new development could be granted planning permission if it would further damage the Stodmarsh lakes.

One of the lakes at Stodmarsh troubled by pollution. Photo credit: Louis Walker.

Tom Scott-Heagerty, Lead Adviser for Sustainable development for Natural England in Sussex and Kent, detailed the process Natural England went through to come to their conclusion.

“A condition assessment was done on the reserve lake and that's when we collected water quality evidence that the lakes are in poor condition, nutrients were causing eutrophication and then the knock-on effects thereafter.

“We updated the Stodmarsh designated site to declining as a conservation status. Then we soon advised local planning authorities that they could not add to the existing pressure under the (2018) European court ruling. Any housing developments that would increase nutrient loads arriving in the Stodmarsh would need to be offset and that’s where nutrient neutrality was born in the Stodmarsh catchment.”

For Canterbury, any developments that had previously gained planning permission had seen their requirements changed with the need to reach nutrient neutrality. This meant that housing developments had to prove they are ‘nitrate and phosphate neutral’ and come up with strategies to move forward.

Two short-term solutions have been addressed in Canterbury. One involves using new land to create wetlands that create nutrient credits which can be purchased by developers to offset their damage.

“The main solution with phosphate is to create wetlands and they are very expensive, so there's a risk financially for local authorities. So this scheme which has been funded by Defra, and channelled by Natural England, is designed to take a bit of that risk away from local authorities.

“The plan is to give financial support, get schemes up and running and then once credits are bought Natural England will get some of that money back that they put in, which will go towards other nutrient credit schemes,” said Mr Scott-Heagerty.

Any agreed planning permissions were revoked after the new Stodmarsh requirements. Photo credit: Scott Graham on Unsplash.

Another solution, which has enabled Canterbury developments to gain planning permission, has been to temporarily install an on-site tank which can treat the effluent before it is disposed of away from the River Stour catchment.

However, in the long term, Natural England looks to move away from temporary measures.

“It's important to think that nutrient neutrality is supposed to be kind of a temporary measure. It's not supposed to improve the situation. It's just to make sure that it doesn't get any worse,” said Mr Scott-Heagerty.

Fortunately, those looking to fund development in Canterbury are also able to have an eye on the future and past the Stodmarsh roadblock. Karl Elliot, of Clague Architects, is the lead architect for the former Debenhams and Nasons sites on Canterbury High Street. He said that the current setbacks will make his clients push even harder to get approval.

“Developers always have an eye on the future. It's not putting any of our clients off. If anything, that will push them harder now to get some, if not approvals, at least some sort of indication that they're going to get approval.”

However, what started as a plan to revitalise Canterbury has been stalled by this latest issue with even the temporary solutions proving too much for developers.

Mr Elliot stated that currently, both developments are unviable, with neither giving the 20-30% profit a development this size should give.

“It means if the council were to charge for offset credits of £2000 a unit, that becomes £140,000 and that makes the viability even worse. There’s got to be another plan for these because where it is now, we can't afford to buy offsets.”

"The days of the big stores are long gone, we will never see those again."

—Karl Elliot

A new approach to high streets was offered at the Debenhams development. In the 100,000 square foot, occupied by Debenhams until January 2020, a mixed-use approach was the way forward, consisting of 12 retail units and 72 apartments over the three former sites. Currently, this project remains stalled after its planning permission was revoked after the emergence of the problems at the Stodmarsh Nature Reserve.

However, the Nasons site recently gained planning permission after implementing the store and ship solution. This development will pay homage to its history, being renamed Biggleston Yard after the six-generation family business, HM Biggleston & Sons, that used the mid-19th century foundry that can be found on site. Again, this project will transform the site that has been vacant since 2018 into a mixed-use offering, incorporating a new pedestrian arcade, a covered market hall, offices, 33 flats and 32 serviced apartments.

Mr Elliot said that these plans will revamp Canterbury with the flexibility the smaller spaces will offer to entrepreneurs, who can bring a rounded experience to the high street.

“The high street is a bit sad at the moment and these will help regenerate that. The days of the big stores are long gone, and we will never see those again.”

The former Nasons building that has remained vacant since 2018. Photo credit: Louis Walker.

When it came to a time scale to have the developments complete, Mr Elliot was only able to offer speculation that a viable solution to the problems at Stodmarsh was at least three years away.

He said: “The city council is so far behind the curve on sorting this out, and the sewage companies have been advised that they can be investing in their pumping stations, which is great, but again, that's a long-term plan. It's not going to be instant, that's when it starts in five years and then goes on 10 years after that, so it's not gonna happen overnight.

"We lost Nasons, then we lost Debenhams and there is a massive hole in the centre of Canterbury."

—Sarah Wren

Although the plans provide food for thought for the dynamic direction this area of Canterbury wants to move in, the situation for current business owners is very bleak.

Sarah Wren, Managing Director of bistro Oscar and Bentleys, has been left in an impossible situation.

She said: “From our point of view, we lost Nasons, then we lost Debenhams and there is a massive hole in the centre of Canterbury. For all the local businesses you need residents, tourists are great, and students are great but you need residents to live here all the time to keep our businesses going.

“I've heard people on the high street, up at the top of town, Go Oh, there's nothing down that way and you'll go well that's main Canterbury; you've walked around the shopping centre and now go oh, there's nothing down there and that's really sad for Canterbury.”

Oscar and Bentleys have had a tricky existence in its nearly ten-year history on Guildhall Street. The award-winning neighbourhood bistro is committed to the path to net zero, wanting to champion local food and in turn reduces its food miles.

However, being in a Georgian building and closing through covid have provided their challenges, which the closures of Debenhams and Nasons have only added to.

“I have been massively impacted by losing Debenhams, losing Nasons and the Debenhams project had a builder, a developer ready to go, ready to push the go button two years ago and nothing has happened because of all the issues with Stodmarsh and how to do the drainage,” said Ms Wren.

The one positive on Guildhall Street has been the addition of the restaurant Franco Manca in 2022, which has been a prime example of what Ms Wren wants on Canterbury High Street.

“It's vibrancy, you need vibrancy, it doesn't matter whether they're coming to us or next door or wherever they're going. You need people to go, oh, that's cool, we should go there. You need that all over the centre of Canterbury to make Canterbury vibrant again, which I think it will become because Canterbury is incredible. It's a gorgeous place.”

One of the former Debenhams sites, opposite Oscar and Bentleys. Photo credit: Louis Walker.

Empty units are impacting visitors exploring throughout Canterbury, as more people merely use the high street as a route to get from one place to another. Canterbury BID chief executive Lisa Carlson explained the impact that moving developments forward in Canterbury could have on the rest of the area.

“It would have an immediate impact on all their neighbours because when you're walking somewhere and you see a big vacant unit you don't necessarily look beyond that. It would have an immediate impact on all the businesses right around that area, but also the people living here. Those of us who live here, work here, study here, having more on offer in the city would certainly help.”

Although major elements of the high street have remained empty, Canterbury is still seen as a prime location that continues to rebound post-Covid-19, despite the Stodmarsh problem.

"Retail doesn't need no space, but it does need less or different space."

—Lisa Carlson

According to the Canterbury BID, there has been a 9.7% increase in visitors to Canterbury, compared to last year, with retail spending also up 11.6% on 2019, the last normal trading year pre-Covid. Changes to the way we shop are more relevant than ever but after a strong increase, online sales, excluding food and beverage, now only account for 24% of spending.
These statistics create a positive picture alongside the 42 openings and only 23 closures Canterbury has seen over the last 12 months.

Although Canterbury continues to recover well, it is developments that are being halted by Stodmarsh that could take them to the next level, with the move towards mixed-use, Canterbury can react to the trends emerging on in its retail space.

“Retail doesn't need no space, but it does need less or different space. There have been some interesting trends going on instead of going brick-and-mortar to online, the reverse has happened as well. You're seeing different showrooms open where you have an online retailer that then opens a brick-and-mortar space,” said Ms Carlson.

“The other trends we're seeing, which is why Nasons and Debenhams are stuck, is that increasingly in towns and city centres, you're getting residential above with commercial at ground floor and quite right you know, we need more housing.”

Debenhams' current appearance on the Canterbury High Street. Photo Credit: Louis Walker.

The need for more housing has been supported by Canterbury City Council, which is currently under special measures for not reaching the housing targets laid out by the government.

Over the period April 2018 to March 2021, Canterbury City Council have delivered 65% of their target for new houses built, meaning they are one of 51 councils across the country below the 75% threshold to escape sanctions.

Councillor for Blean Forest, to the northwest of Canterbury, Barbara Flack wants to pursue more housing to meet the government's target.

She said: “Well the principal reasons why we haven't hit our housing targets have been the Stodmarsh neutrality issues, and not being in a position to grant permission on a lot of developments.

“Not to have been able to develop two prime sites in our city centre has an economic impact. Within Canterbury, we are luckier here, than in other towns and cities our High Street has recovered quite well post-Covid but if you are a visitor and you walk through our city and you see these buildings lying empty, it doesn't instil confidence.”

Although short-term solutions, like the store and ship incorporated at Biggleston Yard, are seen as the way forward to get developments moving again, a sustainable long-term solution still needs to be identified.

“If a long-term solution comes on board, it's not going to happen straight away, there's going to have to be time for it to be fully implemented… The important thing is not to find the solution and then overburden that solution that you put yourself back in the same position again,” said Ms Flack.

“I find it quite extraordinary that we're even considering going into tankering sewage away."

—Nick Eden-Green


In the short term, a quick fix could enable developments to progress but some are critical of implementing them to tackle the new requirements at Stodmarsh.

Councillor for Wincheap, Nick Eden-Green, dismissed the store and ship as a solution to the problem.

He said: “I find it quite extraordinary that we're even considering going into tankering sewage away. There must be proper facilities which do not in any way adversely affect the Stodmarsh area.

“I actually welcome the fact that we're going to have more people living in the city. I think that we need to look at repopulating the cities. So, in principle, I'm absolutely in favour of it. However, if there are problems dealing with the ensuing sewage and waste, that has got to be addressed, with a proper, viable, long term and sustainable solution first, before we agreed to build the houses.”

One proposal that Eden-Green suggested for the housing problem in Canterbury was to develop a garden city outside of the existing urban area.

“We don't have large companies or large industries in Canterbury. It's the heritage value that drives our local economy. From a tourism point of view, we must ensure that we conserve and enhance the historic city centre and not spoil it, and access to it with further excess traffic or indeed, turning what is at the moment, a small intimate city into a much larger one.

“If we're going to have to build the number of houses that the two local plans are calling for, the only ways to do that successfully would be to look at a properly designed sustainable new town or new garden city development, rather than just tacking on miscellaneous suburbs and housing estates to the existing urban area.”

Canterbury Cathedral provides the city with a captive audience, all they need is the encouragement to explore. Photo credit: Louis Walker.

Regardless of where the developments take place in Canterbury, the Stodmarsh will still be an issue until a long-term solution is put in place. A vital player in finding a solution is Southern Water, the wastewater treatment plant operator for the Stodmarsh catchment.

In their statement released in November 2020, Southern Water detailed that if the investigation into the Stodmarsh lakes indicated that future improvements are necessary to improve effluent quality, then significant investment would be required to increase nutrient removal at wastewater treatment works.

This would be funded through the ‘Business plan’ for delivery in the period April 2025 to March 2030. During the statement, Southern Water said: “It is unlikely any improvements required could be delivered before March 2030.”

Lead Adviser for Sustainable development for Natural England in Sussex and Kent, Tom Scott-Heagerty detailed the work currently being done by Southern Water and how beneficial this could be to solving the Stodmarsh problem in the long term.

He said: “So, they have a big part to play in this. Currently, they are undergoing an investigation into all the wastewater treatment plants in the catchment that are likely to impact Stodmarsh and then it proposes upgrades to them. That report will come out eventually and that will give a timescale and list the investment needed for the wastewater treatment works.

“That hasn't happened yet. The report is just being finalised. But once that's issued, then they will secure funding and upgrades to these wastewater treatment plants. That will hopefully mean that the permit limits, the concentration of nutrients in the effluent, will decrease. That will be beneficial to the River Stour and Stodmarsh.”

The importance of treating the environmental issues surrounding the Stodmarsh Nature Reserve cannot be understated. However, a currently unknown long-term sustainable solution appears to be the only way to allow the city of Canterbury to continue to develop and thrive while supporting the two universities, numerous residents and a thriving tourism market that calls it home.

Feature image credit: Louis Walker

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