- ENGINEERING INFO
- CASE STUDIES
The City of Lewiston, the second largest city in Maine, recently faced a dilemma common to many communities across the United States; replacing an aging water main without significantly disrupting the community and nearby businesses. Traditional open-cut excavation to remove the existing 10-inch cast iron water main on the busy thoroughfare of Park Street would have required partial lane closures and significant restoration. Trenchless installation of Fusible PVC® pipe installed via pipe bursting used the existing utility alignment and provided a cost-effective option for Lewiston’s replacement needs.
Working with the City of Lewiston during the project design phase, Matt Timberlake and Shawn Ready of New England-based contractor, Ted Berry Company (TBC), determined that pipe bursting would be a cost-effective solution for the Park Street installation. With its favorable ID/OD relationship, Fusible C-900® pipe allowed Lewiston to maintain hydraulic flow without upsizing the new water line – key factors to a successful installation. Fusible C-900® pipe also enabled the City to install a fused pipeline that can be maintained going forward using industry standard waterworks fittings and installation techniques. With a modulus of elasticity of 400,000 PSI, PVC’s pipe stiffness allows for use of standard ductile iron fittings for connections – making reconnection both convenient and cost-effective for Lewiston.
Another significant factor driving trenchless installation was the number of utility conflicts associated with the project. The water main alignment was in proximity to numerous high voltage electric lines and vaults, communication lines, and gas line crossings. In order to ensure no existing utilities were damaged during the water main installation, TBC exposed the existing utilities to observe the new water main during installation. The technique, known as “potholing,” was completed using hydro-excavation in 32 separate locations prior to pipe bursting. Potholing and accurate utility location were also important in establishing pit locations for the pipe installation. TBC worked with the project engineers to modify the design plans at the project execution stage.
TBC fused the 8-inch DR14 Fusible C-900TBC fused the 8-inch DR14 Fusible C-900® pipe on-site just prior to pull-in. TBC’s licensed and trained fusion technicians used a McElroy 618 fusion machine with carbide facer blades and a DataLogger® 4 for quality control. The fused pipe sections were pulled back through the cast iron host pipe using a HammerHead® HydroBurst™ HB100 pipe bursting system. The bladed rollers split the existing pipe, with the bursting head and expander displacing the host pipe fragments into the surrounding soil. The new pipe was pulled into place simultaneously. pipe on-site just prior to pull-in. TBC’s licensed and trained fusion technicians used a McElroy 618 fusion machine with carbide facer blades and a DataLogger® 4 for quality control. The fused pipe sections were pulled back through the cast iron host pipe using a HammerHead® HydroBurst™ HB100 pipe bursting system. The bladed rollers split the existing pipe, with the bursting head and expander displacing the host pipe fragments into the surrounding soil. The new pipe was pulled into place simultaneously.
By using pipe bursting to install Fusible C-900® pipe, the City of Lewiston minimized disruption to the community and successfully navigated multiple utility conflicts. Successful planning, coupled with the right products, enabled the City to save time and money on the water main replacement project.
|Pipeline Details and Project Summary|
|Project:||Park Street Water Main Replacement|
|Pipe Size:||8” DR 14 Fusible C900®|
|Owner:||City of Lewiston|
|General Contractor:||St. Laurent & Sons Excavation, Inc.|
|Pipe Bursting Contractor||Ted Berry Company, Inc.|