Whitstable’s sewers have entered their AI era
Southern Water’s latest fix, fire station risk, toxic caterpillars, a delayed Ramsgate Lidl, and bikers head to Margate anyway
This week’s Kent Current leads with Southern Water’s AI-controlled sewer system in Whitstable, where smart gates are being used to reduce storm overflows while major upgrades continue at Swalecliffe. There's also council meetings across Kent, Medway’s £46m housing plan, fire station concerns, and the latest mix of infrastructure, planning, culture and local stories from across the county.
Whitstable’s sewers have entered their AI era
Southern Water says AI-controlled gates are already helping reduce storm overflows around Whitstable, but the wider fix still rests on years of work at Swalecliffe and stopping rainwater from overwhelming the network.
The company says a 'smart sewer' system is now operating beneath the seaside town, using real-time artificial intelligence to manage flows through the network during heavy rainfall.
The system is focused on Tankerton Circus and Diamond Road in Whitstable, with wider treatment works upgrades taking place at nearby Swalecliffe, between Whitstable and Herne Bay.
Southern Water says the technology is already running around the clock and is expected to cut storm overflows at Tankerton Circus and Diamond Road by more than 30%.
It is the latest phase of the company’s attempt to reduce storm overflow use in a town where the sea is not just scenery. Whitstable’s beaches, bathing water, oyster trade and coastal economy are central to its identity.
The technology itself is not quite as sci-fi as the phrase 'AI sewer' suggests. Southern Water is using a product called CENTAUR Gates, which can control stormwater flows through the sewer network in real time.
In plain English, the system uses sections of the existing pipe network as extra storage during heavy rain. When stormwater levels rise, the gates can hold and manage flows rather than immediately sending excess water through storm overflows.
Southern Water says the aim is to prevent treatment sites from being suddenly overwhelmed by surface water, reducing the need to release stormwater into the environment to stop homes and businesses from flooding.
The work has focused on new manholes, pipework, and upgraded monitoring systems using radar technology, as well as the smart gates themselves.
Southern Water is now presenting the system as already delivering results.
The company says last year's work delivered an average 'spills-saved' rate of 32% across three combined storm overflows, which it describes as a “clear and measurable reduction in predicted spills.”
That wording is doing some work. Southern Water is not simply saying recorded spills have fallen by a third. It is talking about predicted spills saved, based on modelling of what would otherwise have happened.
That does not make the intervention worthless. It does mean residents might reasonably wait to see what shows up in the actual overflow data before treating the system as a proven fix.
The smart sewer work is only one part of the Whitstable programme. Southern Water says it is investing more than £90m at Swalecliffe Wastewater Treatment Works to modernise the site and increase capacity.
Swalecliffe sits at the centre of the local wastewater system serving this stretch of coast. What happens there has direct consequences for the beaches at Tankerton and Whitstable.
Work already completed includes the replacement of the storm outfall pipe, with the next phase focused on replacing inlet screens at the works.
Southern Water's project page for Swalecliffe lists an estimated investment of £73.5m, with work starting in February 2024 and completion not expected until 2030-31. The company’s latest release puts the figure at more than £90m.
Either way, this is not a quick fix.
Southern Water has also previously said it carried out a £750,000 optimisation of Swalecliffe Wastewater Treatment Works in 2023, after the site’s storm tanks were not being used to full capacity.
According to the company, the work allowed 450 litres of stormwater per second to be redirected during heavy rainfall and stored in an extra 1,800 cubic metres of capacity. Southern Water says that optimisation reduced storm overflows by 36%.
The same earlier update said the site had been using its long sea outfall around 100 times a year before the optimisation.
Southern Water has since replaced the sea outfall pipe at Swalecliffe with a longer one, meaning that any storm overflow releases are discharged farther out to sea and farther from local beaches and bathing waters.
That is an improvement in where releases happen, but it is not the same as stopping releases altogether.
The company says there was one storm overflow release from the new outfall between July 2024, when it was installed, and the end of September 2025.
Across Whitstable, Southern Water says teams are also surveying pumping stations and sewers, sealing parts of the network and delivering nature-based schemes designed to slow the amount of rainwater entering the system.
If less rainwater enters the sewer network all at once, there is less pressure on the system during heavy rainfall, and less need to use storm overflows.
Southern Water says more than £300m will be invested across Kent over the next five years to reduce storm overflows, as part of its wider £1.5bn Clean Rivers and Seas Plan.
Jerome Corcoran, Pathfinder Project Manager for Southern Water, said: “Whitstable is a priority for us, and this programme shows the scale of action we’re taking. We’re combining major investment with some of the most advanced technology available to deliver lasting improvements.”
“By using artificial intelligence to actively manage our sewers, upgrading our treatment works and working with nature to slow the flow of rainwater, we’re tackling storm overflows from every angle. It’s a long-term approach, but it’s already delivering results, and it will continue to make a real difference for local bathing waters over the years ahead.”
Southern Water’s difficulty is that almost anything it says about sewage now arrives with years of public mistrust attached.
The wider numbers remain grim. Top of the Poops, an excellent name for a deeply depressing data site, says Southern Water has recorded more than 1.4m hours of sewage overflows in available data since 2020, but notes that some data may be missing or inaccurate.
Its live-data summary estimates over 169,000 hours of Southern Water overflow activity in 2025 and 164,000 hours so far in 2026. The site cautions that live data is of poor quality and that its estimates may differ from official figures. Despite that, it still seems ominous that the figure is already approaching the total for last year. In its 2025 analysis, the site lists the River Medway among the rivers most polluted by Southern Water, with over 2,500 hours and 567 incidents.
Southern Water is making its Whitstable claims against the backdrop of a wider collapse in trust in the water industry, where sewage discharges, ageing infrastructure, debt, dividends and regulation have all become part of the same public row.
In Whitstable, that row is not theoretical.
SOS Whitstable, a campaign group formed by sea swimmers in 2021, has become one of the most visible local voices on sewage pollution. The group emerged after a public meeting with Southern Water that campaigners felt failed to address concerns about the impact of discharges on swimmers, wildlife and Whitstable’s oyster and fishing economy.
Over the weekend, the group held its latest protest, marching from Tankerton lifeguard hut along the coast to Swalecliffe Treatment Works. SOS Whitstable said the protest was aimed at a water industry it believes continues to harm the environment, public health and the town’s coastal economy.
Speakers included campaigner Feargal Sharkey and campaigners featured in the documentary Dirty Business.
That is the backdrop against which Southern Water is now talking about AI sewers, smart gates and nature-based solutions.
The technology may well be useful. Better real-time management of the sewer network is obviously preferable to a system that simply buckles every time heavy rain hits the coast. Making better use of existing pipes and storage is also likely to be cheaper and less carbon-intensive than building new storm tanks everywhere.
But the harder truth is that Whitstable is getting an AI sewer because the existing system still struggles during heavy rain.
The company wants residents to see a system being modernised. Many in Whitstable will see a water company trying to recover public trust one overflow at a time.
Southern Water can call it smart, pioneering or AI-powered if it wants. People in Whitstable are more likely to judge it by a simpler measure of what ends up in the sea.
Council matters
Meetings this week:
- Canterbury: Planning Committee will decide on 300 homes, a local centre, and a new secondary school in Herne Bay on Tuesday.
- Kent: Standards Committee meets on Wednesday to discuss the number of complaints made against councillors in the past year.
- Maidstone: Council will debate setting up a Maidstone Town Council, councillor allowances, and litter on Wednesday.
- Canterbury: Council will meet on Thursday to debate changes to the constitution, a community governance review, and more.
- Sevenoaks: Council meets on Thursday to discuss waste strategy, workforce retention, and ownership of the Stag Theatre.
- Thanet: Cabinet will discuss Dreamland's scenic railway, Pride in Place funding, property disposals, and more on Thursday.
New planning applications:
- Maidstone: Screening opinion for 300 new homes east of Staplehurst.
- Tunbridge Wells: 36 new homes in Cranbrook.
In brief
🚒 Some on-call fire stations in Kent are likely to face closure.
🧑💻 GPs in Kent keep losing internet access.
🐛 Toxic caterpillars have been spotted near Whitstable.
🚇 Work has begun on a new tunnel to connect Ebbsfleet and Bluewater.
🛒 Costco has revealed full plans for its planned store in Aylesford, including two new road junctions to facilitate access.
🚫 Development of a new Lidl store in Ramsgate has been delayed because lizards were spotted on the site in 2020.
🏘️ Medway Council has agreed to move forward with a plan to spend £46m purchasing nearly 800 social properties.
🏛️ Folkestone Town Council has reached an agreement to purchase the former Folkestone Library building from Kent County Council.
🏨 £20m could be spent restoring a historic hotel in Margate.
🏢 A vacant office building in Folkestone town centre will be converted into 26 flats.
🛥️ A historic swing bridge in Gravesend has reopened.
🪪 Volunteers recruited by Kent County Council to improve communication with the traveller community have resigned, saying no one listened to them and a council staff member used derogatory slurs.
🏳️🌈 Dover Pride will no longer hold an annual event and will instead focus on year-round support for LGBT+ people.
🚽 The Folkestone Dispatch has been talking to the man behind the 'insulting' plans to convert a disused toilet block into a war memorial.
🎭 Marlon Brando really liked Faversham, apparently.
👳 Thousands of people attended a parade to mark the Sikh festival of Vaisakhi in Gravesend.
🏍️ The official Margate Meltdown, where thousands of bikers descend on the town in May, has been cancelled, but the bikers are expected to come anyway.
🏭 Remembering the Norman motorcycle factory in Ashford.
🪖 Meanwhile, residents of the town are fighting to keep its tank.
🏪 An interview with the manager of Grove Green Tesco in Maidstone.
🏡 A nice house in Folkestone.
🧖 Broadstairs could be getting a sauna.
🇯🇵 It's fair to say that the opening of Tokyo Toys in Sittingbourne was a success.
Kent is large, messy and often faintly absurd. The Kent Current is backed by readers, which means we can report on it properly. An annual subscription costs £1.15 a week and helps make that possible.
Property of the week
This week’s property is a big, slightly ridiculous Victorian villa in Westgate-on-Sea, one road back from West Bay, with six bedrooms in the main house plus a self-contained one-bedroom annexe on the lower ground floor for anyone who likes their guests kept at a respectful distance. The ground floor does the period-but-updated brief well, with a grand entrance hall leading to a large kitchen and dining space with an island and bi-fold doors opening onto a terrace, plus a separate lounge with cornicing and an original fireplace. Upstairs, the rear rooms get partial sea views, and the main bedroom goes full boutique-hotel with a balcony running the width of the house and a freestanding copper bath by the fireplace, because subtlety is clearly not the point here. Outside, there is a long driveway, a landscaped rear garden, and an insulated log cabin with power that could be an office, a studio, or simply somewhere to hide. It is on for £750,000.
Events this week
📖 Thu 30 Apr - Dave Rowntree // An evening with the Blur drummer, who will talk about his new book and perform a DJ set. Quarterhouse, Folkestone. Tickets £18.
📖 Thu 30 Apr - Robin Ince: Normally Weird & Let the Quiet Ones Rise // Comedian, author and broadcaster tours his latest books. Fort Road Hotel, Margate. Free. // Also at Herne Bay Comedy Club on 6 May.
🐈 1 - 4 May - Festival of Cats // Cat related art and activities across Margate. Various locations. Free.
📚 From 1 May - Tunbridge Wells Literary Festival // 30 speakers over ten days of events, including Brian Bilston, Iain Dale, Peter Bradshaw, and Rory Bremner. Various locations. Various prices.
Footnotes
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