Earlier in 2017, Ruekert & Mielke, Inc. (R/M) designed a water main replacement project for the City of St. Charles, IL, utilizing the horizontal directional drilling (HDD) installation method. While this section of water main is only 700’ long, it is a 12” diameter main that forms a critical loop for the City, and was in immediate need of replacement. Utilizing the HDD method of installation, the City saved nearly 25% over an open-cut and auger alternate method of construction.
When R/M and City staff first met to discuss the project, it became apparent that traditional open-cut methods of installation would be quite challenging given the project constraints. The existing main was under the pavement of Tyler Road, a four-lane major thoroughfare with relatively high traffic volumes and speeds, which was recently reconstructed. This short stretch of main also passes under a deep drainage ditch, and a railroad right-of-way, which are within 100’ of each other. There was very little right-of-way outside of the pavement area, and to get under the ditch the main would have to be 16’ deep. The close proximity of the railroad right-of-way and the drainage ditch compounded the complexity, as the railroad required the pipe to be in a steel casing. As such, the water main could not simply be installed by HDD using one long pull, but instead had to be split into two pulls; one under the railroad with a casing pipe, and another, much deeper pull under the drainage ditch with no casing pipe.
The project was bid with PVC C-900 pipe, but the contractor submitted an alternate to use ductile iron pipe, which was accepted by the City. The contractor also chose to use HDD for all areas of pipe installation, even those sections where open-cut was allowed, which they felt would be easier and save time, money, and restoration costs. The project was completed in November of 2017, and came in under budget.
Contact an expert today to learn more about whether HDD is a good option for your next project.
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Ruekert & Mielke, Inc. Staff