- ENGINEERING INFO
- CASE STUDIES
Incorporated in 1865, the City of Lockport, New York – 18 miles east of Niagara Falls – is home to beautiful scenery and a rich history associated with the Erie Canal. Since 1816, when it was decided the Erie Canal would pass through Lockport, the area surrounding the city’s center and present day City Hall have become a busy focal point for government and business. When the 80 year-old, 12-inch diameter cast iron water main running under Main Street directly outside of City Hall began to fail, engineers were faced with the difficult task of replacing the line without significantly disrupting traffic or the city government operations.
“The use of Fusible C-900® pipe to make this repair was an important part of our orginal design. When obstructions were encountered, Fusible C-900® pipe was critical to maximizing the interal diameter and flow of this line for the City of Lockport.” Michael T. Marino, P.E., CRA Infrastructure & Engineering, Inc.
The City of Lockport enlisted the experience and engineering services of CRA Infrastructure & Engineering, Inc. to identify a solution for the failing line. CRA, based in Buffalo, New York, is experienced in both traditional pipeline construction techniques and trenchless solutions. CRA quickly recognized that an open-cut approach would be too disruptive to traffic and business on Main Street during construction.
|Pipeline Details and Project Summary|
|Project:||Main Street Pipe Bursting Project|
|Pipe Size & Length:||400 LF of 8” DR18 Fusible C-900® pipe|
|Owner:||City of Lockport|
|Engineer:||HDD / Jack & Bore|
|Owner:||CRA Infrastructure & Engineering, Inc.|
|Contactor:||Kandey Co., Inc.|
Because the unlined, 12-inch cast iron water main serves as a key component of the city’s water supply, significantly reducing the cross-section flow area would have affected the hydraulics of the aging distribution system. The 12-inch main was so deteriorated that no rehabilitation technique could provide a long-term solution for the city, eliminating rehabilitation from consideration. CRA determined that trenchless techniques should be evaluated to install a new pipeline to maintain or improve hydraulic capacity.
Local, experienced site development and trenchless contractor, Kandey Co., Inc., was awarded a contract to complete a pipe burst of the 12-inch cast iron line using 12-inch DR18 Fusible C-900® pipe. Preliminary construction work revealed the presence of an undocumented gas pipeline installed directly above the 12-inch cast iron main and a large cement vault poured around the water main to house telecommunications lines. It became immediately apparent the existing line could not be pipe burst.
Kandey and CRA worked together to identify a solution to the issue. With limited options, CRA conducted a flow analysis to identify exactly how much capacity could be taken out of the line without adverse effects to the rest of the system. It was determined that sliplining the 12-inch cast iron pipe with an 8-inch DR18 Fusible C-900® pipe would adequately address this problem. In November 2014, Kandey contracted Underground Solutions, Inc. to supply and fuse 400 LF of 8-inch DR18 Fusible C-900® pipe. Kandey cleaned the existing water main and pulled in the new 8-inch Fusible C-900® pipe with a small winch.
Fused PVC pipe proved to be an optimal material for the City of Lockport, which required a trenchless installation with the largest possible cross-sectional flow area. PVC’s 4,000 psi hydrostatic design basis (HDB) maximized cross-sectional flow compared with an equivalent diameter and pressure-rated HDPE pipe (HDB of 1,600 psi).