Bnsf Railway Intermodal mitigation Site
Johnson County, Kansas
BNSF Railway's 433-acre, $250 million intermodal transportation facility near Edgerton, Kansas was permitted to impact more than 17,300 linear feet of streams, 16.6 acres of open water, and 4.6 acres of wetlands. As compensatory mitigation for these environmental impacts and to satisfy local storm water regulations, they created a 59-acre conservation corridor which included more than 7,700 feet of a relocated stream designed to match the channel dimensions, meander pattern and slope profile of a natural reference reach/condition. The site also included in excess of 31 acres of restored riparian corridor (including 14.3 acres of created wetland), 8.8 acres of enhanced existing riparian corridor (including 2.4 acres of created wetlands), and 7.2 acres of restored wetlands.
This mitigation project represents one of the largest local on-site efforts for habitat creation in conjunction with storm water runoff treatment. Approximately 300 acre feet of annual runoff is routed through the wetlands to remove minor pollutants. In addition, a portion of the site was designed to meet state requirements to replace listed snake species habitat, including the creation of brush piles and rock structure cover areas. These conservation improvements were designed by HDR Engineering, constructed by Swallowtail, and monitored by Terra Technologies. Swallowtail will retain site ownership, provide long term financial assurance bonds, and maintain the mitigation site.
Constructed in 2011-2012, this mitigation site has met all of its performance standards and has been released from formal monitoring, which included annual inspections, stream and vegetation data collection, and an assessment of species establishment and relative coverage. Swallowtail is now performing long-term management of the site.