Maryland State Highway Administration

Key Services

  • Natural Resource Inventory
  • Wetland Delineation and Functional Assessment
  • Natural Resources Technical Report
  • Environmental Impact Statement

Project Details

The I-270/US 15 Corridor provides an essential connection between the Washington, DC metropolitan area and both central and western Maryland. It is an important corridor for carrying local and long distance trips, both within and beyond the Corridor. The purpose of the I-270/US 15 Multi-Modal Corridor Study was to investigate options to relieve congestion and improve safety conditions along this Corridor. The limits for this study extend from I-370 in Montgomery County to US 15 at Biggs Ford Road in Frederick County.

The I-270/US 15 Corridor is currently served by a variety of transportation modes (including interstate highway, high-occupancy vehicle lanes, commuter rail, and bus service) and intermodal opportunities (including park and ride lots and Metrorail).

Despite the variety of modal options available, the Corridor is highly congested. These problems are expected to become more severe as continued growth in population and employment occur over the next quarter century. Between 2000 and 2025, a 19% increase in population is expected in Montgomery County and a 50% increase in population is expected in Frederick County. As the expected growth occurs, additional development will occur in response, thereby causing increased congestion.

CRI collected existing environmental data for geology, topography, soils, surface waters, groundwater, floodplains, fisheries, aquatic and terrestrial habitat, wildlife, and RTE’s. We conducted field investigations of wetlands, forests, water resources and wildlife habitat for a Natural Environmental Technical Report and Draft Environmental Impact Statement document for the multimodal (highway and transitway) corridor in Frederick and Montgomery Counties.

CRI completed a wetland delineation of a 25 mile highway corridor along US 15/I-270 from Biggs Ford Road to Shady Grove Road and along a 12 mile transitway corridor. We delineated and mapped over 20 acres of wetlands within the corridor. We then performed functional assessments for all wetlands within the study corridor using the EPW methodology. Finally, CRI coordinated and led agency field reviews to obtain jurisdictional determinations.

CRI evaluated and quantified natural resource impacts for each project alternative and coordinated with regulatory agencies to address their concerns. CRI identified permitting requirements and responded to public and agency comments on project NEPA documents and worked closely with project engineers to refine alternatives to avoid and minimize impacts.