River waves · building, running, surfing

Leash and safety at river waves

In April 2025 a surfer died at the Eisbach in Munich. Her leash – the cord between ankle and board – had caught on something under water, the current pushed her down, other surfers could not free her; only the fire brigade cut the cord with a knife. The accident has changed the rules at every German river wave. This article brings together what the operators have required since then, what the technology offers, where it has gaps – and how we want to deal with it at the Remswelle.

Why a leash in a river is different from the sea

In the sea the leash is taken for granted: it keeps the board with the surfer, and whoever falls drifts with the board in calm water. In a river this reverses. The water flows constantly in one direction, the wave is shallow, beneath it lie concrete, rocks and the obstacles that shape the wave. If the leash or the board catches on such an obstacle, the current pulls the body downstream – and the cord holds it in place, flat beneath the surface. At one metre per second of current, forces act on a lying body against which you cannot stand up, and the ankle is then out of reach. Reports from river waves in Canada, where as early as 2013 two surfers only narrowly survived and one died, describe exactly this pattern. That is why many river waves say: better no leash than one that does not release.

What happened at the Eisbach

The Munich I public prosecutor's office investigated the case and closed it in summer 2025. Its report states the facts: the accident happened at night, shortly before half past eleven, at a low water level. The ankle leash held the surfer under water; the state criminal police office found no defect in the leash itself. As the cause, the prosecutor's office considers it conceivable that the board or leash snagged on one of the boulders in the stream bed, without being able to prove it. The surfer died eight days later in hospital. It was the first fatal accident at the Eisbach wave in four decades.

What the operators require

The operators' responses differ – from recommendation to ban. What stands out is that only one wave names a number.

Two things stand out. First: the stronger the supervision, the stricter the leash rule – Pforzheim, with a wave warden and two lifeguards, bans it altogether, while the Eisbach, with no operator, relies on self-release and the buddy on the bank. Second: nobody except Hanover defines exactly what "releases under load" means. There is no standard and no independent testing.

What the market offers – and what is missing

Since the accident, leashes with magnetic couplings have been selling. The principle: between the cord and the ankle strap sits a pair of magnets that come apart at a certain pulling force. A supplier from Hanover offers versions with a release force of around 20 kilograms for surfers up to 100 kilograms and around 35 kilograms for heavier ones, plus a model with an elastic section that dampens force peaks so the coupling does not open at every fall. A manufacturer from Germany builds a coupling based on a magnetic-mechanical fastener from bicycle accessories that releases at about 30 to 35 kilograms and can be closed again by hand afterwards; it warns itself that the coupling does not help if the cord wraps around the body, because then no pulling force reaches the ankle. From Scotland comes a leash for whitewater stand-up paddlers with a patented magnetic connection to the waist belt that releases under sustained load; the manufacturer does not publish its release force. All other systems – waist belts with shackles from whitewater sports, couplings with a pull pin, the safety release used in kitesurfing – are released by hand, and in the current the hand is often not free.

What does not exist: a leash whose release force can be set like a ski binding – by weight, experience and current, with a scale and tested calibration. Nor is there one in the patents of the last forty years; all describe couplings that you open yourself. The requirement from Hanover, below 0.2 kilonewtons, is the only number one can go by, and whether it suits a heavy surfer in a strong current or releases falsely too often has not yet been measured by anyone. Here a piece of technology is missing, and a test standard is missing. We consider this an open task that the river waves should work on together.

The other building blocks of safety

The leash is the most conspicuous building block, not the only one. Built waves are safer than natural ones because their surroundings can be designed: a run-out zone without obstacles, in which a fallen surfer drifts freely into calm water; a wave floor without edges and gaps in which something can catch; an installation that is lowered during a flood instead of someone having to decide whether it is still possible. Then come the rules of operation: a helmet, because you surf close to concrete; surfing hours in daylight; one at a time; a supervisor who can intervene, or at least a buddy on the bank who is not in the water themselves; a briefing for everyone who is new. Nuremberg and Hanover show that a club can provide this. → Operators and operation

How we want to prevent accidents at the Remswelle

The Remswelle does not exist yet, and its operating rules will be set with the operating body, the insurer and the authorities, not on this page. But we say today what we will go by: the strictest rules that exist at German river waves, not the most relaxed. For us that means: an adjustable installation that comes out of the water during a flood; a run-out zone that is free of obstacles – for the variant at the stepping stones this is a question the planning must answer before it is built; operation only with supervision and at fixed times in daylight; helmets compulsory; a leash only if it releases under load, with a limit as in Hanover, otherwise none; a briefing for everyone. And we want not only to read the experiences of the other waves but to share them with them – the accidents at the Eisbach and in Canada happened at waves that had existed for a long time. If you think along similar lines or know better, write to us: info@remswelle.de.

Frequently asked questions

Is a leash compulsory or banned at river waves?

Each wave decides that for itself. Pforzheim bans it, Nuremberg and Hanover allow only self-releasing leashes, Munich has required since 2026 a leash that releases under load, or none at all. When in doubt, the rule at built waves is: surf without a leash, the board drifts into the run-out zone.

What is a magnetic leash?

A leash with a magnetic coupling between the ankle strap and the cord. If the pull exceeds a certain force – depending on the model about 20 to 35 kilograms – the connection opens and the surfer is free. It is the current state of the art, but without a standard and without an adjustable release force.

Isn't a helmet enough?

A helmet protects the head on contact with concrete or your own board and belongs at every built wave. It does not help against being held under water; for that you need the leash rule, an obstacle-free run-out zone and someone who can intervene.

What rules will the Remswelle have?

That will be set by the operating body, the insurer and the authorities once the wave exists. We will go by the strictest existing rules: supervision, helmet, fixed surfing hours, leash only self-releasing or none, installation out of the water during a flood.

Sources: Staatsanwaltschaft München I (Munich I public prosecutor's office), press release 2/2025 (Eisbach investigation) · Landeshauptstadt München, Referat für Klima- und Umweltschutz, Allgemeinverfügung zum Surfen am Eisbach (general order on surfing at the Eisbach), 08.05.2026; Rathaus Umschau, 11.05.2026 · Leinewelle e.V., terms of use (enercity-leinewelle.de) · Nürnberger Dauerwelle e.V., "Surfen" · blackforestwave e.V., FAQ · Riverbreak, "Your life on a leash", 25.06.2013 · Rapid Surf Shop, magnetic leash product pages · Edgeboards, releash · Lodestone Leashes, FAQ; SUPboarder, 19.02.2026 · Google Patents US5643028, US5685751, US5775965, US5957741, US20140315455, WO2017197106 · Wende et al., Orthopaedic Journal of Sports Medicine 2023 (injuries in river surfing)

Last updated: 15 October 2026 · Initiative Remswelle