CompositesWorld
Issue link: https://cw.epubxp.com/i/576646
OCTOBER 2015 68 CompositesWorld WORK IN PROGRESS By Peggy Malnati / Contributing Writer » More than a century of engineering efort has made the Chicago River — a 251-km long system of rivers and canals that snakes through urban Chicago, IL, US — into what the American Society of Civil Engineers (ASCE, Reston, VA, US) today considers a "civil engineering monument of the millennium." One result? Water quality has improved dramatically in the past 30 years, according to Margaret Frisbie, executive director of the Chicago-based conser- vation group Friends of the Chicago River (Friends). A downside, however, is that in many areas of the system, the downed trees and natural riverbanks that created good fsh habitat and would ordinarily be present have been replaced with concrete seawalls, thus preventing the return of healthy fsh populations to the now improved river environment. To address the loss of fsh habitat and encourage healthy repopulation, Friends worked with the Illinois Department of Natural Resources (IDNR) to design nesting cavities for channel catfsh, a native species that surveys had shown should be more abundant in the system. Te simple cavity design mimicked an underwater hollow log. It was designed using Basalt-reinforced polyester rebar extends useful life of concrete habitat units in Chicago River environmental restoration effort. Composite rebar strengthens riverbed "catfish houses" Composites promote conservation To encourage the return of catfsh to the Chicago River, representatives of conservation group Friends of the Chicago River, the Illinois Department of Natural Resources, Urban Habitat Chicago, Ozinga RMC, students representing several other Chicago non-profts, and Asimow Landscaping gathered to produce 50 demonstrator fsh habitat and spawning units (FHSUs). Source | Ozinga RMC Inc. 31-cm-diameter PVC pipe cut to 81-cm lengths and attached by steel cables to concrete blocks to weigh the pipes down and keep them on the bottom of the river. Te plan was to install 400 fsh habitat and spawning units (FHSUs), introduce 100,000 baby channel catfsh, donated by IDNR, that would mature in the river and, ultimately, see them use the FHSUs as nesting cavities. Before FHSU production began, Friends had an opportunity to consult with Brian Lutey, VP – sustainability at Ozinga Green Building, a division of Ozinga Bros. Inc., a Chicago-based builder and concrete supplier. He examined the initial FHSU design and suggested that there was a better way to make them. Lutey is active on the board of another non-proft called Urban Habitat Chicago (UHC, Chicago). Te group's mission is to demon- strate the viability of green infrastructure, urban agriculture and materials reuse/recycling, and to work with disadvantaged and at-risk youth. He knew a microbiologist and fsh expert from that board, so they met to discuss the needs of catfsh and the possi- bility of using Ozinga's Filtercrete "pervious" concrete in FHSUs.