The Board of Supervisors approved a design amendment to the Waddle Road interchange project Wednesday that will see some additional costs to the contract between the township and the Erdman Anthony engineering firm.
The project goes out to bid by March, township engineer Doug Erickson said, where it will transition into a design-build project.
“The contractor who gets the bid will be responsible for the final engineering,” he said.
In order to wrap up the preliminary engineering and design phase, Erickson said, the township proposed adding additional items to the contract with Erdman Anthony — conducting noise monitoring, modeling and analysis; providing final structure foundation reports; completing a design for erosion control and stormwater management plans; and completion of the National Pollutant Discharge Elimination System permitting process.
The amendment will cost $234,883, he said, bringing the total value of the contract to $1.1 million.
The Waddle Road interchange project was proposed to supervisors in December. Designed to relieve congestion, replace an obsolete bridge and accommodate growth and development, the project will see the eventual replacement of the Waddle Road bridge that crosses Interstate 99, connecting the residential and business sections of the township with the Toftrees area.
When construction begins, the existing bridge will remain open to traffic while a new four-lane bridge is constructed next to it on the western side. When that new bridge is completed, it will be opened to traffic so the existing bridge can be removed and an additional four lanes will be constructed.
The final bridge will have a 5-foot sidewalk, a 10-foot shoulder, two 12-foot through lanes and a 12-foot turning lane on both the north and southbound sides. The bridge will also be higher above the interstate to meet height regulations.
Construction is also expected to stretch to Strouse Avenue in order to widen the road.
About $12 million has been earmarked by the state Department of Transportation for the project, Erickson said. Once the project goes to the design build phase, it becomes a PennDOT project.
The interchange is expected to be completed by the end of 2016, he said.