Unusual “Construction From Above” Approach Is Environmentally Friendly

The T. Tyler Potterfield Memorial Bridge is an adaptive reuse of the dam, providing a non-­motorized, universally accessible route across the James River rapids, connecting south bank Manchester & the James River Park System with north bank downtown Richmond. The 1,700-­foot­ span sits just 20 feet above the scenic falls of the James River and is the first pedestrian structure to span the entire width of the James River.

The design and construction team faced some unusual challenges as the project got underway. The location of this project, being within the floodplain of the James River and other environmentally and historically sensitive areas, created for a very complex process.

Before construction could start, the team had to successfully permit the design through five different state and federal agencies (USACE, DEQ, VMRC, DGIF, DHR), as well as the City of Richmond to reach final approval.

Originally, the team’s construction approach was envisioned through the use of a causeway—however, in order to protect the local fish migration, the U.S. Army Corps of Engineers placed a moratorium on work in the James River between February 15 and June 30. This created significant challenges with the project’s tight schedule for completion.

So, to complete the work in the allotted timeframe, the project team decided to use an innovative “top­-down” approach to building the bridge.

A custom gantry crane proved to be a creative and environmentally friendly way to utilize the existing bridge structure as a means of horizontal material transport, while minimizing disruption to the riverbed and habitat below.

The project supported Richmond’s sustainability goals in two primary ways:

  1. successfully re-using an existing dam structure, and
  2. applying a construction from above approach to protect the annual James River fish migration (and other environmentally sensitive areas) below.

Since its completion, the Potterfield Bridge has proven to be a wildly successful recreational amenity, quickly becoming a destination and focus of the social and cultural life of Richmond.

The project team included the City of Richmond, AECOM, Howard Shockey & Sons, Inc., Hargreaves Associates, Moffatt & Nichol, VHB, and others.

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