Portugal’s Helder Silva competes in the men’s 200m Canoe Single during the International Canoe Sprint Challenge on Rodrigo de Freitas Lagoon in Rio de Janeiro, Brazil, Friday, Sept. 4, 2015. Canoeists at the Olympic test event complained Friday about the polluted water at the venue, but they were most outspoken about the aquatic plants that were tangling with their oars and rudders. An Associated Press, five-month water analysis published July 30 showed astronomically high levels of viruses in all Rio Olympic water. (AP Photo/Felipe Dana)