By Rebekah Morris for Arizona Builder’s Exchange
As part of the process of moving toward the 2016 start of construction for the Loop 202 South Mountain Freeway, Arizona Department of Transportation crews will begin the preliminarily geotechnical investigation in early May, assessing the condition of soil, rock and depth of groundwater along the freeway alignment. In addition to the geotechnical testing, ADOT has issued an RSOQ for General Engineering Consultant Services due in late June.
The engineering consultant will be tasked with assisting ADOT with the procurement, evaluation, and selection of the eventual team who will design, build, and maintain the new section of freeway. The selected consultant may not be on one of the three short-listed teams. ADOT is slated to make the final selection by the end of 2015 for the $1.9B project.
Subsurface Conditions Assessment
A geotechnical investigation is designed to provide engineers with data on conditions below the surface, helping to refine construction plans and processes. It will involve soil borings at most future bridge locations – including several at the lengthy Salt River Bridge – and rock coring, test pits up to 10 feet deep and other data collection.
In all, there are expected to be 49 test borings along the future freeway alignment at depths ranging from 25 to 130 feet below the surface. This equates to about 3,600 feet of soil boring and 870 feet of rock coring.
Materials collected will then be analyzed to create a profile of subsurface conditions. That data will be used to help refine plans being created by the three development firms that have been selected to submit comprehensive proposals to design, construct and maintain the freeway.
SR 202 Design/Build/Maintain Solicitation Still Under Review
The freeway will be constructed with four lanes in each direction – three general-use lanes and one HOV lane – and modern features that have made Arizona freeways stand apart from other states for a generation, including rubberized asphalt and aesthetics designed in partnership with the community. The $1.9B project is expected to take about four years to construct.
Read more at ADOT