RCP Withstands Washout, US 17/92 Restored

Orange City, Florida. During Hurricane Milton, heavy rainfall and flooding washed out the southbound lanes and median of US 17/92 (Volusia Avenue in Orange City. Stormwater runoff overtopped the roadway and compromised the 1:2 embankment. Reportedly, the roadway was inundated with between three and four feet of runoff due to the breach of an adjacent private pond and debris clogging a storm drain.

Image 1: The embankment and roadway were washed out, yet a 36-inch diameter RCP storm drain remained in place, along US 17/92 in Orange City during Hurricane Milton on October 10, 2024. (Photo credit: Melitza Avila, Rinker Materials)

The subsidence of the embankment exposed a 36-inch diameter reinforced concrete pipe (RCP) storm drain spanning in a southeast to northwest alignment at a cover depth of approximately five feet within the southbound roadway embankment. The 36-inch RCP, which was installed in the late 1990s, remained in its alignment with filter fabric-wrapped joints intact despite the surrounding embedment and embankment having been washed away.

Image 2: P&S Paving restored the embedment, embankment, and roadway surrounding the 36-inch diameter RCP along US 17/92. (Photo credit: Florida Department of Transportation).

P&S Paving performed the emergency repair contract for the Florida Department of Transportation (FDOT). The roadway repairs were completed and the roadway was restored within five days of the washout. According to US 17/92 record drawings and adjacent property surveys, an additional 36-inch RCP cross drain traverses from east to west several feet beneath the washout, as well as all of the reconstruction activity. Since the RCP was resilient to the flood and embankment washout and needed no repair, the actual work consisted of taking the opportunity to re-wrap the filter fabric and primarily restoring embedment, embankment, and roadway around both RCP drainage systems.

Image 3: FDOT and P&S Paving completed the emergency repairs to restore US 17/92 within five days on October 15, 2024. (Photo credit: Screenshot of FDOT Youtube post, October 16, 2024).

The US 17/92 washout is similar to a circa 1930s washout in St. Petersburg, Florida.  In both cases, the surrounding embankments were washed out and exposed 36-inch diameter reinforced concrete pipe systems completely intact.  In the 1930s, the concrete pipe joints were grouted with a rigid mortar; the concrete pipes in the US 17/92 case were installed in the late 1990s using rubber gasketed joints wrapped with filter fabric.

Image 4: Circa 1930s.  A washout left this 40-feet section of 36-inch diameter RCP suspended and inteact in St. Petersburg, Florida. (Source: Concrete Pipe Lines, American Concrete Pipe Association, 1942)