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 — four riders on every wave.
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 on the primary peak and two more on the reform behind it. Four 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.
4
Two on the primary A-frame, two on the reform section inside it.
−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.
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 — 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.
07 — Constraints
These are the things that could stop the scheme. They are listed here because a proposal that hides them wastes everybody's time — and because each one has a route through it that we want tested early rather than late.
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, not an afterthought.
The Parks Trust is a self-funded charity with a public-benefit remit, not a commercial landlord. The scheme has to argue its case on access, community participation and stewardship — with the commercial return as the mechanism that funds those, not as the headline.
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 a precondition rather than a mitigation exercise.
Sailing, paddle, managed open-water swimming and angling are established uses with established communities. The lagoon takes roughly a fifth of the activity basin. If that displacement can't be designed around to the existing users' satisfaction, the scheme should not proceed.
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 needs to be costed into the base case rather than added later.
08 — Status
This is a concept study. Nothing on this page is consented, surveyed or contracted. It is published to open conversations with the landowner, the operator and prospective delivery partners.
● Current
Wave geometry, bathymetric massing and system layout defined. Indicative only.
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.
09 — Get involved
We're speaking with the landowner, the venue operator, local surf and adaptive-sport clubs, and investors who understand community leisure infrastructure. If that's you, get in touch.