BACKGROUND

Drainage systems are critical components of any type of construction and flooding is always a risk to consider when completing public works projects. Maintenance and rehabilitation to storm water systems must be performed quickly and efficiently to prevent significant damage being done or incurring higher costs to municipalities.

In April 2016, a two-lane highway in Ontario, Oregon, experienced a serious situation when a corrugated metal pipe (CMP) failed, creating a void underneath the roadway. Corrosion and a partial collapse 20 feet inside the 30-inch diameter CMP brought forth significant leaks which softened the surrounding soil. As a result, the topsoil and asphalt gave way, collapsing the road in the compromised area. This resulted in a large sinkhole opening-up on the side of the road, presenting the need for an immediate fix.

Assistant District Manager Jeff Berry from the Oregon Department of Transportation (ODOT) was charged with assessing the problem. The ODOT’s objective was to quickly and successfully stabilize the roadway in order to prevent a larger sinkhole from forming. Because the culvert was located under a crucial road, the main challenge was finding a way to replace or rehabilitate the pipe without further disrupting the traffic pattern on the road above. A significant obstacle was the culvert’s placement. With 10 feet of fill between the CMP and road, the ODOT determined a rehab project would take four days to dig and replace the pipe.

SNAP-TITE® SOLUTION

NW Relining LLC, an Olympia, Washington-based company, is a distributor for Snap-Tite® products.

Sales reps Grey Langemo and Bob Boyes teamed up with Berry to find a solution that would save time and money.

CONCLUSION

Successful sliplining of the culvert with Snap-Tite®.

They decided to use 115 feet of 24-inch, high-density polyethylene (HDPE) pipe to slipline and rehabilitate the existing CMP. The annular space was filled with grout to hold the liner in place. Though the diameter of the pipe decreased, the hydraulic flow capacity is improved.

The Snap-Tite® system will never rust or corrode. It is durable and long-lasting. The primary alternative to Snap-Tite® – digging up and replacing the pipe– would require the city to close the road, disrupt the flow of traffic, and cost the city large amounts of money and time. The new Snap-Tite® liner won’t leak and will last for decades to come, far outlasting the pipe it rehabilitates.

“Snap-Tite® was able to provide us with a quick and efficient solution for rehabilitating the defective CMP culvert,” commented Berry.

A unique feature of Snap-Tite® is that it does not require fusion to join the HDPE pipe together, making installation comparatively easy and inexpensive. The patented male/female machining at each end of the HDPE allows the pipe ends to be ‘snapped’ together, piece-by-piece, and pushed into the full length of the existing pipe. NW Relining LLC was able to provide training and support on the proper methods of sliplining HDPE. With this knowledge the crew was able to quickly and independently rehabilitate the damaged CMP and begin work on repairing the sinkhole.