Open Water Swimming·Water Sports

World Aquatics

🏛️Official — World Aquatics

World Aquatics Open Water Swimming Rules· 2026 World Aquatics Open Water Swimming Rules — 5 km, 10 km (Olympic marathon swim), and 25 km distances; team relays at World ChampionshipsOpen source

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swimsuit, goggle, fins

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Section 1: Introduction

Open Water Swimming is the discipline of competitive long-distance swimming in natural bodies of water — oceans, lakes, rivers, reservoirs — governed internationally by World Aquatics (renamed from FINA in January 2023). The Olympic marathon swim (10 km) was added to the program at Beijing 2008. World Aquatics-sanctioned distances are 5 km, 10 km, and 25 km, plus team relays (4 × 1.25 km mixed-gender) at the World Championships. Open water differs from pool swimming in several core ways: drafting and contact are allowed, navigation is the swimmer's responsibility, and weather + water conditions are part of the competition.

Section 2: Equipment

Swimsuit: World Aquatics-approved suit (textile-only since 2010); men's suit max from waist to knee, women's max from shoulder to knee
Cap: mandatory event-issued numbered cap (high-visibility colors)
Goggles: permitted (anti-glare recommended for sun)
Wetsuit: permitted at water temperatures below 18°C (mandatory below 16°C); prohibited above 20°C; optional 18-20°C
Body markings: race number marked on both upper arms in waterproof ink
No fins, paddles, or buoyancy aids; no electronic timing/positioning aids carried by swimmer

Section 3: Playing Area

Course: closed loop typically 1.25 km or 2.5 km, multi-lap for 10 km and 25 km
Turning buoys: large inflatable navigation buoys at each corner; swimmers must round on prescribed side
Feeding station: floating dock or pontoon where coaches can pass food/drink to swimmers via long poles (10 km and 25 km only)
Water temperature: minimum 16°C (race may be cancelled below); maximum 31°C (race may be cancelled above)
Course depth: minimum 1.4 m for safety

Section 4: Players & Officials

Individual race (mass start) at 5 km / 10 km / 25 km
Team relay: 4 swimmers (2M + 2W mixed) × 1.25 km each at World Championships
Officials: referee, course umpires (on motorized boats), feeding-station judge, timing officials
"Yellow card / red card" warning system enforced by course umpires on the water
Independent finish-line camera (touch pad at finish gantry)

Section 5: Rules of Play

Start

Mass start: all swimmers enter water at signal (typically from pontoon dive-in)
False start rules apply — second offense = disqualification

During the Race

Drafting allowed — swimmers may swim directly behind another to reduce drag
Contact tolerated provided not deliberately obstructive (no pulling, no submerging opponents)
Swimmer responsible for own navigation — must round each turning buoy on prescribed side
Feeding station: coaches may pass food/drink via long pole; swimmer must collect without leaving water or holding pole

Finish

Race finishes at a touch pad on a floating gantry — swimmer's hand contact registers final time
Photo-finish protocol for close finishes

Section 6: Scoring

Individual race: lowest elapsed time wins
Top-10 typically separated by <30 seconds in elite 10 km races
World Cup series: round points → series standings
Olympic qualification: based on prior World Championship + continental qualifier results
Marathon Swim World Series ranking maintained by World Aquatics

Section 7: Violations & Penalties

Yellow card: warning (impeding, holding, kicking deliberately, illegal feed)
Red card: disqualification
Two yellows: automatic disqualification
False start (2nd offense): disqualification
Cutting course (wrong side of buoy): red card
Receiving outside assistance: red card (other than authorized feeding-station hand-off)
Doping: WADA Code; World Aquatics-administered testing program

Section 8: Safety Considerations

Open water swimming presents unique risks: hypothermia, hyperthermia, drowning, jellyfish/marine-life contact, navigation hazards. World Aquatics mandates: water-temperature pre-race measurement (race cancellation thresholds at 16°C and 31°C); on-water rescue boats every ~200 m of course; spotters on shore + on boats; safety swimmers in water; on-site medical (ambulance + EMT + team physician); helicopter evacuation plan for remote venues. Mandatory pre-race medical clearance + cardiac screening. Buddy / partner-pairing system between coaches and athletes at each feeding station. AED at finish line. Concussion / aspiration protocol after any submersion incident — swimmer pulled, medical evaluation, conditional return-to-water authorization required. World Aquatics suspended/postponed events for water quality (e.g., Paris 2024 Seine deliberations) — water quality testing pre-race may delay or cancel competition.

World Aquatics

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Full Rulebook(10 sections)

Overview

How to win

The game

Section 1: Introduction

Section 2: Equipment

Section 3: Playing Area

Section 4: Players & Officials

Section 5: Rules of Play

Start

During the Race

Finish

Section 6: Scoring

Section 7: Violations & Penalties

Section 8: Safety Considerations

Playing the ball

Fouls & penalties

Equipment

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