Petersen Engineering was recently awarded 2 emergency pipeline replacement projects. The first one was awarded on August 17th for the replacement of 3 – 8″ pipelines crossing the Missouri River at Decatur, NE. Flooding of the Missouri River at this location caused significant erosion and washout of the lines just outside the river channel.
The second project was awarded on September 14th to replace an 8″ crossing of 1100′ near North Blenheim, NY. This project was the result of flooding that was caused by Hurricane Irene. Petersen Engineering was already working in this area on another HDD creek replacement project.
All of these replacement projects were to be performed using HDD method.
The pipelines at the Missouri River project were shut down as a safety precaution. Therefore, time was of the essence in getting the replacement lines installed. A preliminary new route was selected and Petersen had personnel on site on August 24th to meet with the surveyor and show the project to three bidders.
The original river crossing was approximately 1,000′ in length and was installed by HDD. However to install the new line with the flooding conditions and to allow for a new alignment that was required due to access on the Nebraska side of the river, the new length of pipe installed by HDD was 7,023′ for each line. On the Nebraska side of the river, an additional 900′ per line of pipe was installed by normal lay methods to connect to the existing lines.
In addition to the new line installed by HDD, the valve site on the Iowa side of the river needed to be installed to a location outside of the flood plain. Petersen Engineering worked with client engineers to design a new valve site and prepare fabrication drawings and a bill of materials.
Based on initial field information, a preliminary plan and scope of work was given to the contractors, bids were received and a contractor was selected and on site on September 12th. Actual work started on September 17th. By October 10th, the first line was installed and product was flowing. All work is expected to be completed by October 29th.
The client handled ROW, permitting, procurement and construction inspection. Petersen prepared all drawings, construction cost estimates, Job Safety Plans, surveying, geotechnical investigation and coordinated the pre and post-pull ILI runs of the pipe being installed by HDD.
For the line in New York, Petersen Engineering will be performing on-site field engineering, cost estimation and project planning. Due to the mountainous terrain, the implementation of the bore will have to contend with numerous construction hurdles.