The 606/Bloomingdale Trail Design

Chicago Park District

Chicago, IL

Collins was selected by the Chicago Park District to provide Phase II design for The 606/Bloomingdale Trail, a multi-purpose park and trail system.

The 606
has the elevated Bloomingdale Trail as its centerpiece that connects to six ground level parks. The Bloomingdale Trail is a 13-acre 2.67-mile-long bike and pedestrian path that runs along a former elevated rail line beside Bloomingdale Avenue. The scope of work included the rehabilitation of thirty-eight viaducts; design of two new viaduct structures; repairs to thirty-seven retained embankment sections; design of thirteen points of access to the trail incorporating ADA guidelines for accessibility; and the design of two new parks. Areas of specialty include bridge, civil, and electrical design; architecture and landscape architecture; survey; environmental survey and remediation; community involvement and outreach; cost estimating; and other associated work.

The 606 project offers the City of Chicago an opportunity to create an urban amenity with a distinctive “Chicago Imprint” that will set the tone for similar projects throughout the country. Through its frequent access points, elevation above city traffic, and park environment, The 606 enhances the social and economic vitality of the neighborhoods with which it intersects, creating a unique new way to enjoy daily life in Chicago, and making it easier, safer, and more exciting to travel by foot or bicycle. With the completion of the structural repairs and landscape improvements associated with this project, a piece of early 20th century infrastructure has been repurposed for 21st century needs: connecting communities, improving access to and experience of bicycle networks, enhancing ecological performance, and creating a new type of dynamic urban experience.

The multi-disciplinary team led by Collins also included sub-consultants Michael Van Valkenburgh Associates (MVVA) and Frances Whitehead. MVVA worked on the Phase I design for this project and servef as the landscape and urban design architect. Frances Whitehead—internationally known as an artist-innovator, and producing cutting edge work that integrates art and sustainability—served as the lead artist for this project.

Typical Scope of Work

  • Rehabilitation of thirty-eight viaducts
  • Design of two new viaduct structures
  • Repairs to thirty-seven retained embankment sections
  • Design of thirteen points of access to the trail incorporating ADA guidelines for accessibility
  • Design of two new parks


  • Drainage of the linear site and the desire to employ sustainable storm water practices to reduce the amount of surface runoff to the local drainage system
  • Implementation of storm water filtering methods
  • Providing potable water service to the elevated trail

Actions Addressing Challenges

  • The elevated abandoned railroad was constructed with retaining walls on both sides filled primarily with lake sand, creating a “bathtub” design. Since the presence of sand in the elevated portion of the project is favorable for infiltrating storm water, Collins utilized these properties to promote on-site infiltration to minimize discharge to the local storm sewer. Additionally, storm water is stored in underground basins that have restrictor manholes to reduce the discharge flow rate and, subsequently, the burden on the local storm sewer system.
  • Collins used the design of vegetated swales located throughout the entire project to filter any storm water that does not infiltrate prior to storing in the specially designed underground detention basins.
  • Collins applied unique utility designs that incorporated exposing waterline above ground with proper insulation and guard protection to reduce construction time and cost, traffic disruption, and future maintenance burden.

Project Value

  • Construction cost: $95 million
  • Illinois Section American Society of Civil Engineers, Outstanding Civil Engineering Achievement Award (Projects over $25 Million) - 2015
  • Metropolitan Planning Council, Burnham Award for Excellence in Planning - 2015