- ENGINEERING INFO
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The City of Edmond, Oklahoma, located just north of Oklahoma City, has been one of the fastest growing areas in the state over the last 20 years. The Edmond Public Works Authority operates water and sewer systems that include 525 miles of water mains and 450 miles of sanitary sewer collection lines serving approximately 80,000 residents.
The Summer Oaks neighborhood, constructed in 1983, consists of single family homes on lots roughly one-sixth of an acre in size. The original water distribution system in the subdivision was constructed using ductile iron pipe. Due to the extremely corrosive soils in the area of the neighborhood, those lines started failing in recent years.
|Pipeline Details and Project Summary|
|Project:||Summer Oaks Waterline Rehab|
|Pipe Size:||8" DR14 Fusible C-900® pipe|
|Owner:||City of Edmond|
|Engineer:||Cowan Group Engineering|
When faced with rehabilitating the waterlines in Summer Oaks, the City of Edmond teamed with Oklahoma-based civil engineering consultant Cowan Group Engineering. Together they developed a plan to replace over 7,400 LF of water mains while minimizing the construction footprint and financial impact. As depicted below, there were over 100 residential properties serviced by water mains in need of rehabilitation. Traditional open-cut installation would have been costly due to the required pavement repair.
The goals of minimizing the construction footprint and limiting cost were successfully accomplished using horizontal directional drilling (HDD) and pipe bursting with 8-inch DR14 Fusible C-900® pipe. In total there were nine segments installed using HDD totaling 6,383 LF, one section installed via pipe bursting totaling 941 LF, and 154 LF of open cut installation.
The City received multiple bids with Nowak Construction of Goddard, Kansas selected to perform the work. Nowak had the ability to self-perform all aspects of the project based on their previous experience with HDD and pipe bursting. Following the award, Nowak decided to become trained and licensed to fuse Fusible PVC® pipe. This allowed Nowak to control all aspects of the construction process by utilizing their own manpower. Nowak mobilized onto the jobsite in April of 2013 and worked quickly to complete the project by September of 2013.
Jeff Cowan, President of Cowan Group Engineering, was tasked with the engineering design and specifications for the Summer Oaks Waterline Rehabilitation. Cowan had the following comments regarding the project:
On overcoming the complexity of the project due the dense population and number of waterlines: "With the City's approval, we determined early on in the design process that trenchless installation for the majority of the project was the way to go. We used a combination of horizontal directional drilling and pipe bursting based on what we anticipated would provide the best and most cost effective solution."
On selecting Fusible PVC® pipe for the project: "Fusible C-900® pipe was specified for several reasons. First, it provided a fully-restrained, gasket-less pipe system that was not susceptible to corrosion. Second, it was robust enough to withstand the pipe bursting and directional drilling installation. Finally, Fusible C-900® pipe provided the City with an opportunity to use PVC pipe, a pipe material their maintenance crews are comfortable working with in the event future maintenance is required."
Steve Lawrence, Public Works Engineer with Edmond, on what made this project successful:
"Edmond is home to a well-educated population with high expectations for continuous improvement in services. City personnel make every reasonable effort to minimize construction impacts on residents. Edmond has been using trenchless technology for sanitary sewer rehabilitation for over twenty years. Recently, we have been increasing the use of trenchless methods for water main rehabilitation where appropriate. The project's success was based on effectively rehabilitating an entire neighborhood's water system in the most cost effective manner, using a pipe material that maintenance staff are familiar with in PVC. We accomplished all of this while minimizing impact to residents. We were very pleased with Underground Solutions and the performance of the Fusible C-900® pipe. It's good to have another reliable tool in the toolbox."