African roots inspire professor’s varied water research

By Maegan Murray, WSU Tri-Cities

RICHLAND, Wash. – After growing up in drought-afflicted Ethiopia, Yonas Demissie values water. His research to manage the life-sustaining resource reaches from the U.S. military to the Nile River basin, from Washington’s Hanford nuclear site to biofuels crops and the Gulf of Mexico.

“Here in the U.S., we take water for granted,” said Demissie, assistant professor of civil and environmental engineering at Washington State University Tri-Cities. “Our daily water use is as much as 10 times that of a person in other countries where water is in limited supply” – in Ethiopia, for example, where just 42 percent of the country’s 94 million people have access to clean water.

“Having a good understanding of water as a resource and coming up with a better management strategy is critical for most societies,” he said.

Climate impacts on defense

Yonas Demissie reviews water research data.

He is half-way through a four-year study of the impact of climate change on military infrastructure, focusing specifically on whether stormwater management systems at defense facilities can handle increased flooding and precipitation fluctuations. This research is part of a $1 million contract with the U.S. Department of Defense.

“DOD has many facilities across the globe and many of those installations are close to coastal areas,” he said. “They are worried about sea level rise, increased extreme storms and how that will affect their facilities and operations.”

Effects of runoff from biofuels crops

Researchers, including those at WSU, are making significant strides in biofuels, creating fuels for jet airplanes, cars and more that help reduce the United States’ carbon footprint. But increases in Midwestern crops used to make certain biofuels may be damaging ecosystems in the Mississippi River and Gulf of Mexico.

“In the Midwest, they are making biofuels from corn, which requires increased nitrogen and phosphorus fertilizer applications, which end up in the streams,” Demissie said. “These increases lead to algal bloom, which eventually prevents vegetation and fish from growing in lakes and other water bodies.”

Monitoring Hanford contamination

The B reactor at the Hanford Site.

He works with Hanford Site contractors and Pacific Northwest National Laboratory staff to ensure there is no radiation or other toxic contamination of water sources vital to daily human use, like aquifers and reservoirs. Contamination stems back to Hanford Site production of plutonium during World War II and the Cold War.

“We are consistently monitoring groundwater contamination for Hanford, using various monitoring and modeling projects to tell where it’s flowing and how fast it is traveling,” he said.

Sharing Nile River resources

Flow patterns and allocations of Nile River waters, and how they can more effectively be shared by all nearby African countries, is another of Demissie’s studies. Any water project in the upstream tributaries of the Nile is politically contentious, he said, since countries like Egypt and Sudan use the river as their main source of water and electric power generation.

Yonas Demissie, second from left, and his team in the lab at WSU Tri-Cities.

Ethiopia, where 80-90 percent of Nile water originates, historically was not using the river despite being hit by regular famines caused by highly variable rainfall. However, Ethiopia is now constructing the largest dam in Africa on the Blue Nile, the main tributary of the Nile, for electric power generation.

Demissie and colleagues Gabriel Senay, Naga Manohar Velpuri, Stefanie Bohms and Mekonne Gebremichael completed a study in 2014 that integrated satellite data and modeling to detail the variability of water sources in the Nile Basin.

Their research revealed that about 85 percent of runoff generated in the equatorial region (Ethiopia, Tanzania, Kenya and Uganda) is lost along the river pathway that includes the Sudd wetlands, an area approximately twice the size of Maryland. This proportion is much higher than the previously reported loss of 50 percent.

“Our knowledge regarding water availability in the Nile Basin and how much and where water is lost in the system is limited,” he said. “But our analysis shows that we get more water into the system than was originally estimated. There is extra water that Ethiopia can use.”

He said he hopes his group’s research will prompt more assessment of the direction, flow and amount of water in the Nile, which could lead to legislation among African countries that may result in an agreement that would benefit all.