High above a community of villagers, Nepal’s Imja Lake rises quietly each year, expanding its reach as ice melts from the glacier that towers more than 23,000 feet beside it.
The glaciers and ice-capped mountains surrounding the body of water provide majestic scenery, but they don’t tell the full story of what’s happening at Imja Lake — how it has become the fastest-growing glacial lake in the Himalayas, how its increasing size is considered a consequence of global climate change, and how, if unchecked, it threatens to flood communities 5,000 feet below it.
The lake didn’t exist decades ago. But by the 1960s, water from the melting Imja Glacier began collecting, creating a pool that covered 48,811 square meters. In 2007, the lake’s expanse was 945,662 square meters (or more than 176 football fields).
“Because of this exponential growth, we need to characterize what are the risks of flooding to these downstream communities, and what levels of risk are acceptable,” said Daene McKinney, a professor in the Environmental and Water Resources Engineering Program at the Cockrell School of Engineering. “And if these levels of risk are unacceptable, what options are available to reduce and mitigate them?”
McKinney is part of a group of more than 30 scientists from 15 countries who are trying to answer that question in Nepal, Peru and other places affected by rising glacial lake levels.
Led by McKinney, the research team recently received $400,000 in seed money from the U.S. Agency for International Development to establish the first global network of glacial lake researchers. The funding will provide grants to programs and scientists wanting to research in the field.
The research team has also been invited to partner with the United Nations Development Program, which, along with other agencies, has supported a project to drain Imja Lake.
“It’s exciting and it expands our support from various agencies,” McKinney said of the partnership.
The researchers are not interested in the often-heated debate about global climate change. The reality that they’re grappling with in the field is that glaciers are melting, forming lakes that didn’t exist until recently and creating a ticking time bomb that threatens to put communities under water.
“This lake wasn’t even on the map 50 years ago,” McKinney said, while pointing to a map of Imja Lake hanging in his eighth-floor office in the Department of Civil, Architectural and Environmental Engineering.
Last month, McKinney joined the research team for a second time at Imja Lake. While there from May 3 to June 1, the team combined its collective expertise in engineering, social sciences and geography to study factors such as how quickly ice is melting into the lake and the thickness and strength of the debris that is holding the water.
“There’s a lot of uncertainty about how quickly the ice is melting and how thick the debris layers are,” McKinney said.
Based on the data they collect, the research team will provide residents in the affected communities with several mitigation options for reducing the risks of flooding from the lake.
The options include siphoning the lake to a safe level and digging a drainage canal or installing a pipe so that water can be safely diverted downstream. The latter was done to a glacier lake in Peru, Lake Palcacocha, after it cracked and abruptly flooded a valley below, killing more than 5,000 people in just 15 minutes in 1941.
McKinney said the melting glaciers threaten more than just the villages directly below them. Nine of the major river systems in Asia flow out of the Himalayas.
“So you’ve got an incredibly large portion of the world’s population in India and China that these rivers are supplying fresh water to,” he said. “But as the mass of the glaciers reduces, the supply of water going downstream becomes much more variable.”
Unlike other scientists around the world who are performing similar research, McKinney and his team are collecting on-the-ground data rather than relying on satellite images.
The expeditions have included McKinney and several graduate students, as well as researchers from Peru and Japan. While there, the researchers live in small cabins in the villages or camp in tents near the lake.
The lake is an eight-day hike from the nearest airport and nine miles from the nearest village, and once the researchers are up at the more than 16,000-foot elevation, they must deal with thinning air from the high altitude.
Another key distinction of their research is that the team is working directly with locals affected by the problem.
“It’s nice because they point things out that have changed over the last two or three years, like cracks opening up near the lake. We wouldn’t have noticed all of those things because we weren’t here the years before,” McKinney said. “With their help, we can get a handle on this problem.”
What to watch next:
- The Mountain Institute features a video about Professor Daene McKinney’s expedition to Imja Lake
This story originally appeared on the Cockrell School of Engineering website.