BIA 14 Reconstruction
In February of 2013, the Three Affiliated Tribes of the Fort Berthold Reservation in North Dakota retained Interstate Engineering. The project was to provide preliminary and construction engineering services for the reconstruction of 12.2 miles of BIA Route 14, located south of Mandaree, North Dakota. This route is one of two major accesses through an active oil drilling and production area south of the town and connects ND State Highway 22 with BIA Route 12, west of McKenzie Bay.
The existing roadway was a 28-foot-wide gravel surfaced road in desperate need of repair. The condition of the road was such that traffic could not safely travel more than 15 miles per hour. The road had many soft spots, pot holes, and rutted areas due to the increase in traffic and travel from the oil production growth.
At the time of the design, the road was experiencing an average daily traffic count of 2400 vehicles with 70% of that consisting of truck traffic. A 22-inch aggregate base over a prepared subgrade and fabric and seven inches of hot bituminous surfacing was incorporated into the design.
The existing roadway had seven large centerline drainage structures that needed to be considered throughout the design process. These structures were large corrugated steel plate type culverts and nearly 50 years old. The design removed the old structures, replacing them with reinforced concrete box culverts. The culverts ranged in size from 10-foot by 6-foot boxes to 14-foot by 8-foot boxes.
With the heavy traffic and the topography of the area, it was decided the road would be widened to accommodate a 50-foot wide subgrade. Turn lanes at critical areas along the route were also integrated into the design.Due to the heavy and constant traffic, the construction phasing and traffic control was thorough and meticulous.All of the work done had to be completed within the existing 150-foot right of way corridor. This proved to be the most challenging portion of the design.
In March 2014, the project was bid. An alternative option was offered for contractors allowing for different solutions to the paving section, utilizing either subgrade or aggregate base stabilization products. Before any alternative would be approved, prior testing was needed, and the owner would accrue no cost.
Flickertail Paving, LLC was the low bidder though they came in slightly over the predetermined budget for the project. Flickertail Paving offered some cost savings options, including the use of a cement treated subgrade. This would ultimately reduce the needed aggregate thickness. An agreement was reached in May 2014 which brought the project within budget. Construction began on June 1, 2014.
The revised pavement section utilized a 12-inch cement treated subgrade along with 10 inches of cement treated aggregate base. Due to the concern regarding the stiffness of this section, the overall process was closely monitored throughout construction.
The project was considered substantially complete in November of 2014, leaving permanent striping and rumble strips to be completed during the next construction season.
Over the winter and spring months, the pavement wore considerably from truck traffic and trucks that left chains on their wheels. To better protect the road surface, it was micro-surfaced in 2015. This work was change ordered into Flickertail Paving’s contract and was completed in July 2015. The project was completed in August 2015, 6% under the agreed-upon contract amount.