The Colorado River at Horseshoe Bend about 7 miles downstream of Lake Powell. The period between 2000 and 2019 marked the driest 20-year stretch in the Upper Colorado River Basin since Lake Powell opened. There were only four years in that timeframe during which there were above-average inflows into Lake Powell. Warming temperatures due to climate change have had a significant impact on reducing water flows on the Colorado River. Photo credit: Denver Water.