A heavy snowpack in the Sierra Nevada and rising temperature has mountain rivers running fast and becoming more dangerous. The rising rivers, combined with the swarms of summer vacationers, has officials at California’s national parks worried about the increasing number of drowning incidents. It’s the top cause of fatalities in the national parks. In response, park rangers are stepping up swift water rescue skills to save as many people as possible. One of those training sessions took place in Sequoia-Kings Canyon National Park. Vic Bedoian reports from Cedar Grove.