From the Houston Chronicle:
A paddler participating in the Texas Water Safari, a 260 mile endurance boat race on the San Marcos and Guadalupe rivers, died Monday afternoon at a San Antonio hospital, marking the first fatality in the event's 50-year history.
Brad Ellis, 30, was pronounced dead around 2 p.m. at San Antonio Military Medical Center after he was flown there early Sunday, according to a hospital spokesman.
Ellis died of hyponatremia, or low sodium, said Allen Spelce, president of the Texas Water Safari.
The full story is in today's Houston Chronicle