Mark Lensink, his girlfriend, and her family were enjoying a ride at the base of Iguazu Falls, right where the waterfalls crash down, when the incident occurred. Six Dutch tourists and two Brazilian crew members were aboard the boat during the accident, according to Brazil’s Chico Mendes Institute for Biodiversity Conservation, which manages national parks. In a statement, the institute said it “deeply regrets” the death of the Dutch tourist, which occurred during the Macuco Safari tour Tuesday noon at Iguazu National Park in Paraná state. High water levelsThe Brazilian Navy will now investigate whether the accident resulted from technical or human errors, or environmental and weather conditions. The Iguazu River is experiencing historic flooding, prompting Argentine and Brazilian national parks to close some trails.