The construction of the I‑581 and Valley View Boulevard interchange has greatly improved mobility and safety in Roanoke, Virginia, resolving long‑standing congestion near Valley View Mall, one of the region’s largest retail destinations. As part of a design‑build program led by Lane Construction Corporation, STV provided comprehensive engineering services to redesign the existing partial cloverleaf interchange into a diverging diamond interchange (DDI). This modern configuration enhances traffic flow by eliminating the need for left‑turning vehicles to cross opposing traffic, improving safety while efficiently handling high volumes without adding lanes.
What challenges did STV address?
The existing interchange’s geometry caused heavy delays near Valley View Mall and limited the ability to move vehicles safely and efficiently. STV needed to design a modern layout that fit within the constraints of a busy urban corridor while reducing the interchange’s footprint. The team also faced structural and traffic engineering challenges, including optimizing bridge width and improving deceleration lane performance.
What solutions did STV deliver?
STV designed geometric, structural and traffic modifications to convert the partial cloverleaf into a DDI – one of the region’s first. The redesign reduced the width of the Valley View Boulevard bridge over I‑581 by 37.5 feet and shortened the southbound I‑581 deceleration lane by more than 900 feet. STV’s work improved operational efficiency, safety and constructability while minimizing impacts on adjacent development.
How does this project benefit the community?
The new interchange reduces congestion, enhances motorists’ safety, and improves access to the Valley View Mall area. The design supports smoother traffic flow, reduces conflict points and provides long‑term mobility benefits for residents, commuters and visitors.
Key stats and accolades
- One of the region’s first diverging diamond interchanges
- 37.5‑foot reduction in bridge width
- More than 900‑foot reduction in deceleration lane
- Merit Award from ACEC Virginia
