King Street, located on the east side of Roanoke, VA, required some much needed traffic improvements in order to handle the isolated backups that routinely occurred near the intersection of Orange Ave, also known as Route 460 or Alternate 220.
Drainage modifications along King Street presented a challenge, as the new roadway improvements would require filling in an existing ditch line to accommodate a new turning lane and sidewalk, however the existing ditch line drained through a mix match of old pipe sections, existing box culverts, and a failing CMP multi-pipe culvert under Springtree Drive.
Faulconer Construction Inc. accepted the challenge and solicited the help of CP&P’s Hanover Pipe Plant & Salem Structure Plant to provide precast concrete solutions. The Hanover facility provide RCP for the project which included 584 L.F. of 66” Reinforced Concrete Pipe. Even though some designers tend to forget that 66” pipe is available, simply because it may not be available from “non-concrete” pipe manufacturers, the 66” RCP was the optimal size for this project based upon project constraints and hydraulic flow requirements.
CP&P’s Salem facility provided several custom structures including special junction boxes used to connect the new RCP to existing box culverts and an existing 48” pipe to the system. Salem also provided a modified wingwall for the twin 66” RCP outfall.
Much of the installation occurred at night, because of the routine traffic congestion that occurs during the day at that location. When excavating and removing the failing multi-pipe CMP under Springtree Drive, it was discovered that there were actually four sets of twin metal pipes under Springtree Drive stacked on top of each other. Apparently, as they had settled and crushed over the years, new pairs of metal pipes were simply stacked on top of the older ones instead of removing and replacing the crushed pipe. This had to have happened several times over the life of that particular culvert crossing.
Now, removed and replaced with concrete, the drainage under Springtree Drive should last for many, many years.