An Australian water advocate set out this summer to run the complete length of the Colorado River — roughly 2,000 miles in 100 days — tracing the waterway from its source through Colorado, Utah, Arizona, Nevada, Mexico, and California. The run began at the river's headwaters inside Rocky Mountain National Park, where she navigated a lush alpine meadow with navigation apps, following tiny channels barely wider than a palm as they merged into the modest stream that becomes the Colorado River.
Mina Guli founded the water nonprofit Thirst Foundation in 2012 and has witnessed severe drought firsthand during her upbringing in Australia. In a prior endurance campaign, she completed 200 marathons within a single year leading up to the 2023 UN Water Conference, using the feat to draw attention to global water stress. Her current effort sustains nearly a marathon per day for 100 days, focused on a river that, she noted, underpins $1.4 trillion in economic activity and provides water to more than 40 million people.
The drought conditions she has encountered along the route have matched and often exceeded her expectations. The national drought monitor shows roughly 95% of the Colorado River Basin in drought, and experts who analyzed the situation projected that the river's two largest reservoirs, Lake Powell and Lake Mead, would set new record lows daily through spring. At Lake Powell, she observed water sitting multiple stories below its historical level. Stretches she had planned to navigate by packraft turned out to be shallow enough to cross on foot, leaving the inflatable craft unused in her crew's vehicle.
Wildfires have repeatedly reshaped her planned course. The Snyder Fire prompted evacuations along the river corridor and burned more than 30,000 acres near the Colorado-Utah border, forcing a detour; later, the Babylon Fire in Utah — among the largest wildfires in the country so far this year at over 107,000 acres — required another unplanned reroute. While navigating around the Babylon Fire, she and her crew watched the orange glow of flames after dark and columns of smoke resembling "nuclear mushroom clouds" rising during daylight hours.
The physical demands of the run have worn on her steadily. Blisters have developed on her feet, altitude proved difficult after starting from sea level, and temperatures routinely soared into triple digits — heat she described as "diabolical" — with nights in her tent offering little recovery. She has described how sustained long-distance exertion strips away resilience, leading to simultaneous physical, mental, and emotional collapse.
Throughout the route, she has stopped to speak with farmers, ranchers, raft operators, and fishing guides. Each of those conversations, she said, carried the same refrain: "the river is in a dire place, and that means that their businesses are suffering." She has channeled those accounts into a series of summits connecting policymakers, scientists, water managers, Tribal leaders, and business representatives.
Passing the 30-day mark, she entered the Grand Canyon, where severe heat pushes travel into nighttime hours and requires carrying all supplies on her back — a challenge she acknowledged will call on skills she has yet to fully develop. Whether she will complete all 100 days on schedule is still an open question.