Concept study · Milton Keynes
A 3.5-hectare surf lagoon enclosed within the activity basin at Willen Lake South. Four SwellSpot plungers drive swell across inflatable reef banks to produce a 4–6 ft A-frame that breaks left and right — two riders on every wave, one each way.
Live conditions for Milton Keynes. The wave is machine-generated — it runs to the session timetable in any weather, which is the entire point of building one here.
01 — The wave
Most engineered waves peel one way and carry one rider. A symmetrical A-frame splits at the peak and peels in both directions at once, so a single wave carries two surfers from one peak — one going left, one going right. Doubling riders per wave changes the throughput maths for a community venue — and it produces the shape surfers actually want to ride.
1.2 – 1.8 m
4–6 ft, operator-selectable by plunger stroke and reef inflation.
A-frame
Symmetrical peak, peeling left and right from the same section.
45°
Set by the plan geometry of the reef bank, not by the plunger.
4.6 m/s
About 17 km/h. Fast enough to be a real wave, slow enough to be learnable.
11.9 s
Per direction on the primary peak; around 9 s on the reform.
2
One on the left shoulder, one on the right, from the same peak. The reform bank inside runs as a separate beginner section.
−2.15 m
Depth over the primary reef. Sets where the wave breaks.
−4.60 m
Deep-water paddle-out between the two banks. No walking back.
02 — How it works
The plungers make energy. The reef turns it into a breaking wave. The barrier keeps it inside the lagoon and off the rest of the lake. Remove any one and the scheme doesn't work.
SYS 01
Four SwellSpot plunger units on a shared gantry at the seaward edge of the lagoon. Each drives a vertical displacement stroke; firing them in a phased sequence steers the swell crest into the V that produces the A-frame.
SYS 02
Two submerged inflatable structures shape the lake bed into a crescent bank and a shallower reform bank inside it. Adjusting inflation changes the depth over the crest — which changes where, how hard, and at what size the wave breaks.
SYS 03
A floating rubber barrier wall rings the lagoon, containing wave energy inside the surf area and protecting the rest of Willen Lake. Existing sailing, paddle and open-water swimming continue unaffected on the far side of the wall.
Plunger charge
03 — Location
Willen Lake is two lakes, and the difference matters. The North Lake is a wildlife reserve with a nesting island, a bird hide and the Peace Pagoda — it is excluded from this proposal entirely. The South Lake is the activity basin, already home to watersports, Aqua Parcs, the observation wheel and Treetop Extreme. The lagoon is proposed for the South Lake only.
04 — Concept views
Four viewpoints through the scheme, from the establishing aerial down to the line-up. These are geometric studies, not photography — every wave shape shown is generated from the same model that produced the section drawing above. The film at the top of this page is a generated visualisation: its wave scale reads larger than the design, and it omits the containment barrier. The geometry below is the design intent.
05 — Why Willen
The expensive, slow, planning-heavy parts of a surf venue are car parking, access roads, drainage, food and beverage, changing facilities and a proven visitor catchment. Willen Lake South has all of them, operating, today. The scheme adds a wave to an existing destination rather than building a destination around a wave.
06 — Public benefit
The Parks Trust is a charity, not a landlord looking for rent. So the question that decides this scheme is not whether the wave works — it is whether Willen Lake is measurably better for Milton Keynes with it than without it. These are the targets the scheme should be held to, and the basis on which we would expect a lease to be written.
Participation
Milton Keynes is one of the largest urban areas in England with no coastline and no surfable water. The nearest consistent waves are a three-hour drive. The lagoon puts a genuine progression pathway — first stand-up to competent green-wave surfing — inside a 20-minute bus ride for most of the city.
Schools & young people
A committed block of school and youth-group sessions each week at a subsidised rate, written into the lease rather than offered voluntarily. Watersports is one of the few activity categories where MK schools currently travel out of the city.
Adaptive access
Adaptive surfing needs calm, predictable, repeatable waves and shallow entry — conditions the sea rarely gives and a tunable reform bank always can. A dedicated weekly session with trained volunteers, not an occasional open day.
Jobs
Lifeguards, coaches, front of house, maintenance. Seasonal at the margin but core staff year-round, in a sector that hires locally and trains on the job. The scheme should publish its FTE commitment before consent, not after.
Trust income
The Parks Trust maintains over 6,000 acres across Milton Keynes from its own income. A lease structured with a turnover element means the lagoon's success funds parks that will never charge a penny — the same logic that already applies to paid activities at Willen.
Visitor economy
Willen's activity cluster is weekend and summer weighted. A membership-led surf lagoon runs at 06:30 on a Tuesday in February. That is the shoulder-season, midweek demand the rest of the site cannot generate on its own.
We want these written into the lease. Participation, employment and Trust income commitments belong in a binding agreement, not a brochure — so they are stated here to be costed, negotiated and then held to. We would rather be measured on them than praised for them.
07 — Show your support
Wakeboarding closed at Willen in 2022 because too few people used it. That is the fair question to ask of any new watersport here, and we would rather answer it with a number than an opinion. If you would surf this lagoon, say so. No payment, no commitment — just a count we can put in front of the landowner.
We publish the running total and the number of distinct postcode districts. We never publish names, emails or individual data. The register exists to evidence catchment and demand to The Parks Trust, Milton Keynes City Council and prospective funders.
08 — Sessions
The lagoon is tuned per session rather than run at one setting all day. Inflation and stroke change the wave from a soft reform for a first-timer to a hollow 6 ft peak for an advanced session — the same water, reconfigured in minutes.
09 — Constraints
Every scheme on water has these. Ours are published because we have a route through each one, and because a landowner who finds a constraint themselves trusts you less than one who brought it to them. Each has a defined next step, and none is a reason the scheme cannot work.
The lake's primary function is flood attenuation — collecting run-off and controlling flow into the River Ouzel. Water level is designed to move. Any barrier and reef system must accommodate that range, must not impede storm capacity, and must be demonstrably neutral to the flood regime. This is the first engineering question and a solvable one — floating, moored systems accommodate level range by design, and the barrier is removable. Bathymetric survey and hydraulic assessment are the first commissions.
The Parks Trust is a self-funded charity with a public-benefit remit, not a commercial landlord. That suits this scheme. Access, participation and stewardship are what it is built to deliver, and the commercial return is the mechanism that funds them — including income back to the Trust for the wider estate.
The North Lake is excluded outright. But the South Lake is not ecologically empty either — it carries large numbers of overwintering birds, particularly gulls. Ecological assessment covering both basins, including displacement and winter roosting, is commissioned early so it shapes the design rather than defends it.
Sailing, paddle, managed open-water swimming and angling are established uses with established communities. The lagoon takes roughly a fifth of the activity basin, leaving the majority of open water in place. Layout, siting and season are all adjustable, and existing users are consulted before the design is fixed rather than after.
A balancing lake receives urban run-off. Bathing-standard water quality for a high-contact surf use is a different requirement from managed swim sessions, and the treatment, monitoring and closure protocol is costed into the base case from the outset, alongside the monitoring and closure protocol any supervised water venue already runs.
10 — Status
Concept stage, deliberately. The geometry, system layout and a bottom-up capex build are complete; survey, consent and agreement come next. Publishing now is how we get the landowner, the operator and delivery partners shaping the scheme rather than reacting to it.
● Current
Wave geometry, bathymetric massing, system layout and a bottom-up capex build complete.
Next
Bathymetric survey, water quality, ecology, and a technical feasibility gate with the SwellSpot licensor.
Then
Landowner agreement, planning, environmental permitting and navigation consent for the barrier.
Then
Reef installation, barrier deployment, plunger gantry, wave tuning and operator handover.
11 — Get involved
This is a concept study, so there is nothing to book and nothing to buy. What there is: a set of open questions that the landowner, the city, prospective members and prospective funders all answer differently. Pick the one that fits.
Scott Graham — founder of Surf X Group Ltd, which holds the exclusive UK and EU licence for SwellSpot plunger wave technology. Around a decade working on accessible community surf infrastructure in the UK, alongside a working background delivering energy infrastructure — CHP, solar, battery storage and microgrids — for industrial and commercial clients. Board member at a UK inland watersports venue and an active wake surfer.
