By Linda Fresques
Over the next five years, researchers at New Mexico State University will receive nearly $3 million for the university’s role in a National Science Foundation-funded, multi-university effort to reinvent America’s aging and inadequate water infrastructure. NMSU, along with Stanford University, Colorado School of Mines and the University of California, Berkeley, form the Urban Water Infrastructure Engineering Research Center. NSF will invest $18.5 million in the center over five years, with additional funds to follow for a further period of five years, based on in-progress reviews.
Engineering Research Centers are interdisciplinary hubs established at U.S. universities wherein researchers work in close partnership with industries to pursue strategic advances in complex engineered systems and technologies. The Urban Water ERC, led by Stanford, includes researchers trained in the fields of environmental engineering, earth sciences, hydrology, ecology, urban studies, economics and law.
NMSU civil engineering professor, Nirmala Khandan is co-principal investigator on the project. “At this level of collaboration, we can achieve much more than any one individual campus could alone,” he said. “We are starting with a clean slate and developing entirely new philosophies about how to recreate our urban water systems.”
Khandan serves as education director for the center, along with his counterpart at the Colorado School of Mines.
The cornerstone of these efforts is NSF’s Research Experiences for Undergraduates program, supporting active research participation by undergraduate students in any of the areas of research funded by the NSF. This spring, undergraduates will be selected to work with faculty doing hands-on research over the summer.
The program will also incorporate NSF’s Research Experiences for Teachers, through which middle- and high-school teachers can work with faculty over the summer in water-related areas. Participating teachers are required to incorporate 40 hours of water-related educational activities in their classrooms.
Water-related courses will be developed and offered for undergraduates across all four institutions. Additionally, workshops will be developed for practicing water technicians to expose them to the ERC’s research and new technologies.
Khandan also serves as the leader of the center’s research at NMSU. Other ERC team members at NMSU include Salim Bawazir, Phil King, Shuguang Deng and Bernd Leinauer. Along with these four other NMSU faculty members, he is conducting research that is hoped to lead to new strategies to rebuild the nation’s crumbling water infrastructure.
Khandan’s ongoing research on the use of algal systems to produce biofuel and treat wastewater fits well into the ERC’s goals. For the past three years, he has been building test-beds at the Fabian Garcia Science Center growing different species of algae to determine how much oil can be gathered from each species.
“Algae mainly need carbon dioxide and sunlight to grow,” Khandan said. “But they also need two side dishes: nitrates and phosphates. Municipal wastewater, for example, has plenty of these substances, which is currently a big problem, because they cannot be easily removed from the wastewaters. You can’t just dump them because they will pollute the rivers and ground water. But, we can feed them to the algae and gain multiple benefits of waste management and energy production.”
While Khandan is investigating the optimal conditions for algae growth and providing nutrients from recycled wastewater, chemical engineering Professor Shuguang Deng then takes over, making it usable as a source of energy.
“My group will work on energy extraction and fuel conversion of algae cultivated from wastewater,” Deng said. “The main goal of this task is to identify appropriate conditions for converting wet algae biomass to biofuels and develop efficient processes for extracting high-value products from algae.”
Bernd Leinauer, professor and Extension specialist in the College of Agricultural, Consumer and Environmental Sciences, is investigating beneficial use of treated wastewater. His research focuses on using brine, a byproduct of treated wastewater, for landscaping.
“In the Southwest, 50 to 70 percent of our summer water goes to landscape irrigation. Use of engineered water in landscaping is a great opportunity for conservation,” Leinauer said.
Leinauer is working in conjunction with collaborators at Colorado School of Mines, which is using a bioreactor for treating effluent water with membranes. The process changes the chemical composition of water, creating higher quality water on one side of the membrane and brine on the other side.
“We are investigating how landscape plants react when brine water is used,” Leinauer said. “We’ve found that most grasses are fairly tolerant but trees and bushes suffer. So, maybe the plants we select for use in landscaping need to change.”
Along with increased salinity, engineered wastewater also contains nitrates, which can be beneficial to plants during the growing season, but could taint the groundwater. Nitrates are taken up by plant root systems during growth, but when applied during dormant periods are leached into the groundwater and could make it unsuitable for human consumption. Leinauer and his colleagues are looking at ways to tailor the nitrate level in treated water so that it can be applied to landscaping plants properly.
While Khandan, Deng and Leinauer are investigating beneficial uses of wastewater, Professor Phil King is seeking new ways to capture and use storm water.
“We’ve been experiencing drought conditions in the Southwest for the past 12 years and we are throwing away a resource that we desperately need. We’d be happy if we could just get it back into the groundwater,” said King, civil engineering professor and associate department head.
The typical method of handling storm water is to guide it through a concrete canal system and dump it into the river.
“We are creating a new paradigm for handling storm water by finding ways to capture it and put it to beneficial use,” King said. He is working with the city of Las Cruces and the Elephant Butte Irrigation District on scenarios that have the potential for implementation.
Civil engineering Professor Salim Bawazir is looking at novel methods to manage vegetation in riparian zones to improve and conserve water quality and habitat and apply them in urban settings.
New Mexico, with Colorado, Arizona and Texas, has been waging battle with salt cedar, an invasive species that consumes a lot of water.
“The salt cedar has readily adapted and replaced native vegetation, such as cottonwood and salt grass, diminishing the diversity of the ecosystem and impeding the growth of plants that support wildlife,” Bawazir said.
For many years, the U.S. Bureau of Reclamation has been managing the growth of salt cedar by mowing, plowing and spraying with herbicides. Together, BOR and NMSU are using a 6,000-acre test site near Caballo Reservoir to study salt cedar management via groundwater monitoring stations and satellite imagery to measure evapotranspiration of the vegetation.
“We hope to take what we’ve learned and engineer zones using native plants within urban settings that will have multiple functions,” said Bawazir. “Such areas create microenvironments that support wildlife and are aesthetically pleasing, which might encourage more development and support the economy. They use less water than non-native vegetation and their root systems filter the water, to some extent, removing some of the impurities that would reach the groundwater.”
For more information, visit http://urbanwatererc.org.