August 2013, Vol. 25, No.8

Waterline

Students’ green infrastructure designs win U.S. EPA RainWorks Challenge

College and university students formed teams to compete in the inaugural U.S. Environmental Protection Agency (EPA) Campus RainWorks Challenge. EPA announced first- and second-prize winners in the categories of large and small institutions.  

Student teams worked with faculty advisors to devise plans that use green infrastructure to reduce stormwater pollution on their campuses. Winning teams were selected based on their analysis and planning, preservation or restoration of natural features, integrated water management, soil and vegetation management, value to the campus, and likelihood of implementation, according to an EPA news release.  

The University of Florida–Gainesville won first prize for a large institution. The team’s plan incorporates stormwater ponds, rain gardens, a green wall, a green roof, a campus garden, and bioswales into a 4.5-ha (11-ac) open area and pedestrian corridor, according to EPA’s website. 

The Illinois Institute of Technology (Chicago) won first prize for a small institution. The team’s plan to redevelop a365-m-long (1200-ft-long) section of Dearborn Street incorporates rain gardens, permeable walkways, and retrofits to academic buildings to direct stormwater into a treatment area, the EPA website says. 

The University of Arizona (Tucson) won second prize for a large institution. The team’s design to redevelop a 6500-m2 (70,000-ft2) parking lot includes installing two rings of retention basins to infiltrate stormwater runoff; five underground cisterns to harvest runoff and heating, ventilation, and air-conditioning condensate from the adjacent buildings; and a translucent shade structure with an ephemeral water feature, the EPA website says. 

Missouri University of Science and Technology (Rolla) won second prize for a small institution. The team’s design for three projects include a green roof, rain garden, and permeable pavement in the campus’ northeast quadrant to educate students and reduce nutrient and sediment pollution in nearby Frisco Lake, the EPA website says.  

Learn more at http://water.epa.gov/infrastructure/greeninfrastructure/crw_winners.cfm. 

  

Monitoring wetlands on a microscopic scale 

Microbes, a crucial indicator of wetlands’ health, often are overlooked, probably because they are invisible to the naked eye. Because microbes exist at the base of a wetland’s food chain and nutrient cycle, monitoring them can be used to complement other wetland health evaluation techniques, according to University of Missouri (Columbia) researchers. 

After analyzing wetland microbiological health, the researchers found that a higher ratio of archaea microbes to bacteria was an indicator of a healthy ecosystem. When a few bacteria species dominated the samples, wetlands most likely were contaminated and unhealthy, according to a university news release. 

Advances in microbial analysis enable researchers to more easily and accurately identify microbial species in soil and water samples, said Zhiqiang Hu, a lead researcher for the study and university associate professor of engineering, in the news release. The process was determined to be cheaper and faster than other types of ecosystem assessments, the release says. 

The process could help in choosing where to construct wetlands by determining areas with adequate types of microorganisms, as well as in monitoring these constructed wetlands. It also could help maintain healthy wetlands and wastewater treatment ponds, the news release says. 

The study report, “Toward development of microbial indicators for wetland assessment,” was published in the journal Water Research. 

  

USGS works to update the water census 

Developing a strategy to manage water resources requires information. But this has been lacking since the last comprehensive assessment of national water availability was conducted in 1978. U.S. Secretary of the Interior Ken Salazar has released a report on the progress of this census to the U.S. Congress, according to an Interior Department news release.   

The U.S. Geological Survey (USGS) is working to fill this information gap by quantifying water supply and demand across the country for the National Water Census. The census, a component of the Interior Department’s WaterSMART initiative, fulfills a requirement under the Secure Water Act, part of the Omnibus Public Lands Management Act of 2009.  

The department is working to secure water supplies for use by existing and future generations to benefit people, the economy, and the environment and to identify adaptive measures needed to address climate change and future demands, the news release says. The census will be an ongoing effort, continually updated and improved by USGS, the news release says. 

Read the report, “Progress Toward Establishing a National Assessment of Water Availability and Use,” at http://pubs.usgs.gov/circular/1384. 

  

Nanotechnology employed in floating stormwater treatment system   

A floating water treatment system may be coming to a retaining pond or waterway near you. The Oregon State University Institute for Water and Watersheds (Corvallis) and Puralytics (Beaverton, Ore.) are working together to develop and commercialize the technology with a grant from Oregon BEST (Portland, Ore.), a nonprofit organization promoting the development of clean, sustainable technologies.  

The system uses nanotechnology-coated mesh activated by sunlight to purify water. This technology, incorporated into thin, round pads that float a few inches below the surface of standing stormwater, treats large volumes of water, according to a joint Oregon BEST and Puralytics news release.  

Designed to remove trace chemical contaminants, the technology could help pretreat stormwater, reduce overflows at treatment facilities, and prevent contaminants from reaching waterways. The technology could decentralize stormwater treatment at municipalities and divert water from entering water treatment facilities during storm events, the news release says. 

To evaluate the system, researchers will establish design parameters and generate third-party test data. The research team will construct and closely monitor prototypes of the technology in tanks or artificial ponds. They will examine the technology’s ability to remove contaminants, including metals and organic chemicals, from water, the news release says.