Getting a Fix on Route 66 – Culvert Stabilization

The Challenge

Seepage repairs on a major intersection in California.

The City of Rancho Cucamonga was inspecting damage that was discovered on another construction project and found seepage issues were occurring in the lateral lines below a major intersection of Route 66. They identified joint separation that was leading to Inflow and Infiltration (I&I) into the pipe.  

The City had to balance a variety of issues in order to repair the pipes. First of all this was one of the busiest intersections of the entire city, so having long shutdown periods was not an option. Secondly, as always, balancing their budget while still having an effective repair was something the city was trying to manage. Thirdly, they needed the repair to happen as soon as possible so they could avoid any potential soil subsidence issues that could occur to the roadway intersection.

Key Facts

The Solution

Polyurethane injection was used to seal and stabilize.

Groundworks uses a polyurethane injection process for sealing and stabilizing lateral joints. The process works by injecting a proprietary high-density, water-resistant polyurethane formulation. Once injected, the polyurethane expands and travels throughout voids until the polyurethane has filled the joints around the entire perimeter of the pipe.  This process seals any separation in the joints and cracks and helps re-establish contact between the pipe and the surrounding soils.

The City’s project had some complexities that had to be overcome.  Firstly, the access point for the pipe was via a single manhole, whereby confined space entry certification was required by all crew personnel. Secondly, traffic control was required and Groundworks worked with the City on road closures while additionally monitoring the street surface to ensure the roadway wasn’t lifted.  Thirdly, the pipe was 24 inches in diameter with joints at every 2 feet that required injection from within the pipe!

The Impact

Only 1 lane on Route 66 was closed for 2 days, with minimal impact to traffic flows.

Groundworks accomplished this last feat by crawling into the pipe and predrilling the injection holes prior to injection.  A crew member was fortunately sized for this task and additionally able to perform the injections afterward.  The injections took place every 2 feet with monitoring down the line to watch for travel.  As the polyurethane began to show at the next joint, the crew member would begin injection at the next location. The project took place over 2 days with 8 hours each day and a total of 60 linear feet of pipe sealed and stabilized.  Only 1 lane on Route 66 was closed, with minimal impact to traffic flows at the major intersection.  This was Rancho Cucamonga’s first time using polyurethane injection for I&I mitigation and they were very happy with the results of the work and the professionalism of the Groundworks team.