Olympic Marathon Swim Test Run Halted: Water Quality Concerns After Shorter Race

Triathlon athletes were able to swim in the Seine Monday, but the marathon runs through a much longer section of the waterway.

PARIS, France — A test run for Olympic athletes to familiarize themselves with the marathon swimming course in the Seine River was abruptly canceled on Tuesday due to concerns over water quality in the Paris waterway.

Paris 2024 spokesperson Anne Descamps confirmed that World Aquatics made the decision to call off the exercise.

The decision came just a day after the triathlon mixed relay event was held in the same river. However, the segment of the Seine utilized by triathletes is considerably shorter than the marathon course, which has races planned for Thursday and Friday.

World Triathlon on Tuesday released data showing that during Monday’s triathlon event, levels of fecal bacteria like E. coli and enterococci remained within acceptable limits.