I-70 NEW STANTON INTERCHANGE

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1 I-70 NEW STANTON INTERCHANGE Westmoreland County, PA Submitted by:

2 PROJECT DESCRIPTION Situated adjacent to the PA Turnpike (I-76) and Interstate 70 in Westmoreland County, New Stanton bills itself as a transportation hub where All Roads Lead Home. With both interstates carrying an average of more than 40,000 vehicles per day, the Borough finds itself literally at the crossroads of two major corridors serving western Pennsylvania. But prior to construction, I-70 was outdated and its interchanges were unable to handle traffic safely or effectively. The New Stanton Interchange connects to SR 3093 (Center Avenue). The heavy truck traffic, closely spaced side roads and numerous retail businesses lining Center Avenue contributed to extreme congestion many hours of the day. Many travelers avoided the area for this reason. Safety was another factor driving the project development. The New Stanton Interchange was only 1,800 feet west of the Turnpike and the Hunker Interchange was only 800 feet west of New Stanton. All on- and off-ramps were short, leading to difficulty merging and congestion. The median width was also narrower than current design standards. Lastly, the vertical clearance on I-70 under the Center Avenue Bridge was two feet less than required. These factors contributed to safety issues throughout the corridor. The design team developed a solution to relocate the New Stanton interchange 1,600 feet west of the old interchange, and to consolidate the former New Stanton and Hunker interchanges. The proposed design utilized standard acceleration and deceleration lanes and reconstructed a 1.7-mile stretch of I-70 between Hunker Waltz Mill Road and the Turnpike interchange. The $53.7-million project includes three roundabouts, highway lighting, two new traffic signals, two bridge replacements, one bridge deck replacement, sidewalks along side roads and a park-and-ride lot to encourage carpooling. I-70 traffic now flows safely and efficiently through the project area. Center Avenue congestion has been greatly reduced. New businesses are sprouting up in the area and pedestrians can be seen enjoying the new sidewalks.

3 TECHNICAL The SR 70 New Stanton Interchange involved many challenging and complex design components. The existing configuration contained three interchanges (Pennsylvania Turnpike, New Stanton and Hunker) along SR 70 within 3700 feet of each other. Narrow shoulders and the lack of adequate acceleration and deceleration lanes contributed to a crash rate three times the statewide average for similar facilities. High traffic volumes (43,000 vehicles daily) and heavy truck traffic (29%) contributed to the safety issues. Center Avenue, the main cross-street at the interchange, is lined with retail businesses. Turning movements to and from these local businesses created heavy delays near the ramp terminals. The business owners were vocal about the need to maintain traffic flow to their establishments during construction. The project need was to create a safer, more efficient mainline, increase shoulder widths to match other SR 70 projects, increase vertical clearances to 16-6, and increase interchange spacing to the 2500-foot minimum required by the Federal Highway Administration. Heavy traffic demands led PennDOT District 12-0 to require that four lanes of traffic be maintained on SR 70 at all times, except overnight lane restrictions. Construction also needed to be completed without queuing off-ramp traffic onto the mainline. Another factor that made the project more complex was the presence of several utilities that required relocation. Gas, water, sewer, electric, cable and phone lines were all affected. Lastly, the project schedule was for preliminary and final design, including completing a right-of-way plan and acquiring all properties, to be completed within three years. Fifty parcels were impacted, including four displacements. To meet this aggressive schedule, monthly partnering meetings were held with all relevant PennDOT and FHWA staff in attendance. Design issues were discussed and decisions were made with the entire design team present, reducing the need for multiple submissions and reviews. The schedule was so important that a charter was created and each member of the design team had to sign it, indicating their commitment to achieving the project let date. The proposed solution was to consolidate the New Stanton and Hunker Interchanges and to situate the new interchange 2500 feet west of the PA Turnpike ramps, 1600 feet west of its original location. The project includes 1.7 miles of I-70 reconstruction, three roundabouts, highway lighting, two new traffic signals, two bridge replacements, one bridge deck replacement, sidewalks and a park-and-ride lot. Auxiliary lanes were proposed in both directions between the Turnpike and the new interchange to eliminate weaves. Roundabouts were proposed at the diamond ramp terminals instead of traffic signals due their ability to keep traffic from queuing onto the interstate, to calm traffic and to reduce crash severity. The roundabouts also accommodated the closely spaced intersections at the ramp terminals.

4 INNOVATION The New Stanton Interchange incorporated several unique innovations. One idea was to develop two narrated videos one to communicate what the project would entail and another to show how traffic would be maintained as it was being built. AECOM produced the videos, which were shown at several meetings with project stakeholders, and uploaded to the Department s I-70 website. McDonald s displayed the videos on a loop in their dining area to educate patrons about the interchange improvements and construction. The roundabouts, designed to accommodate heavy truck traffic, are the only ones made of concrete pavement in the Commonwealth. These roundabouts are also the only ones at interstate ramp termini in the Commonwealth. Roundabouts are inherently difficult to plow, especially when the roundabout has bypass lanes. The southern roundabout included maintenance turnarounds, which allow the plows to turn around immediately after plowing a portion of the roundabout. This saves them from traveling up to several miles until they can turn around and return. Lastly, the District used the A+Bx bidding method. This required all bidders to bid a number of days to complete the contract work. Bidders that committed to a shorter construction schedule had their bids lowered accordingly. Pedestrian bridge over I-70 relocated and given a new façade for Fayette County Park Bridge carrying Center Avenue over I-70

5 SCHEDULE/BUDGET The Design Team was able to meet the committed let date of June 15, Joseph B. Fay Company was the low bidder at $53.7 million, which was only 6% over the engineer s estimate. Fay s A+Bx bid was to reduce the construction duration from 1183 days, as designed, to 818 days. This reduced the construction schedule by one construction season. The new interchange opened to traffic in Fall 2017 and a ceremonial ribbon-cutting was held on November 21, UNIQUE CONTRACTUAL CONDITIONS PennDOT used the A+Bx bidding method. This required all bidders to bid a number of days to complete the contract work. Bidders that committed to a shorter construction schedule had their bids lowered accordingly. Joseph B. Fay Company s A+Bx bid was to reduce the construction duration from 1183 days, as designed, to 818 days. This reduced the construction duration by a full construction season. BENEFIT TO SOCIETY The new interchange has moderated traffic volumes along Center Avenue, generally making the retail storefronts more attractive, as patrons no longer encounter congestion. The revised interchange location has also opened up new areas to economic development; several businesses are relocating to the project area. As the side roads were reconfigured and/or reconstructed, sidewalks were added to provide a continuous ADAcompliant path connecting areas north and south of SR 70. Another secondary benefit resulted from removing an existing pedestrian bridge over SR 70, which was removed intact and trucked to Fayette County for use on the Sheepskin Trail, where it now spans a small stream. The 39-space park-and-ride lot at Center Avenue and Bair Boulevard provides travelers with a convenient spot for ride sharing and access to mass transit. A bus pull-off area was provided, along with space for a bus shelter and bike rack. The lot is served by Westmoreland County Transit Authority, providing connections to job sites and other destinations in the County.

6 IMPACT ON SAFETY, HEALTH AND ENVIRONMENT Prior to the project, crash rates along SR 70 were three times the statewide average. The improved geometry, elimination of the weaves between interchanges and increased shoulder widths seem to have reduced crash rates dramatically. The increased vertical clearances will help keep the bridges from being struck by tall vehicles. Roundabouts have been shown to reduce total crashes by 35%, fatal crashes by 90% and injury crashes by 76% when compared to signalized intersections. Prior to construction, Center Avenue had a crash rate six times higher than the statewide average for similar facilities. Reduced congestion and new center turn lanes on side roads are expected to reduce the crash rate significantly. Pedestrians are also safer now since contiguous sidewalks have been added. The new interchange has moderated traffic volumes along Center Avenue, which generally makes the retail outlets more appealing. Eliminating gridlock along Center Avenue results in greater fuel efficiency and improved air quality. The addition of 3800 feet of new sidewalk will encourage pedestrian activities, lowering passenger vehicle usage in the area. Pollution will be reduced and local residents will see increased health benefits from walking. Several steps were taken to reduce stormwater release to streams, and to increase water quality. Three stormwater basins were provided to moderate releases during storm events. Several streams were relocated and improved with features like log sills, rock-lined ditches and step pools. A rain garden was incorporated near Suburban Court to facilitate natural dissipation of runoff when compared to piping. Architectural elements of the project included staining and stamping the roundabout centers, simulating a stone finish. New Stanton Borough selected the color for the bridge beams and monotube signs, and an architectural form liner was used for the exposed concrete barrier on the mainline bridges. Some streams and wetlands were impacted by the project. Rather than acquiring more right-of-way on-site, the design team worked with State agencies to provide off-site mitigation. New wetlands were created at a State Game Lands site in Washington County, while stream improvements were made to Cherry Creek on the Westmoreland County Community College property. Both mitigation sites provided needed improvements while minimizing the project footprint. These innovative solutions represent the future of engineering by not only focusing on moving vehicles efficiently, but also by facilitating multiple modes of transportation and promoting healthy activities like walking and biking.

7 PUBLIC RELATIONS ACTIVITIES The narrated videos mentioned earlier communicated the upcoming project activities in lay terms. The videos were very valuable in showing the public graphically how the roadways would be changing. AECOM, PennDOT and the entire design team engaged in design partnering throughout the project development. Monthly meetings were held with AECOM, our subconsultants and all PennDOT Design Units to discuss project issues, gain consensus and make decisions on-the-spot, rather than waiting for formal submissions. At times, these meetings involved up to thirty people. Project stakeholders were also involved by formation of a Community Partnering Committee (CPC). CPC members represented others in their community group and acted as liaisons to the design team. Our partnering efforts continued into construction, where AECOM representatives attended monthly construction progress meetings with the contractor to answer questions and provide feedback. The contractor also met with the CPC in advance of major traffic control changes. Still view of narrated video showing proposed Park-n-Ride Lot Construction of bridge carrying I-70 over SR3089

8 Since the opening of I-70 New Stanton Interchange, the response from the public, Westmoreland County and PennDOT has been overwhelmingly positive. This type of investing in our infrastructure is vital, and it comes around once in a generation. It will change the face of the community, not just for the commercial companies that use the road but also for our residents. Jason Rigone Westmoreland County Planning Director Source: Tribune-Review article, 11/21/2017 Our transportation mission is to keep people and goods moving safely and efficiently, and this project brings some of the latest industry improvements, like roundabouts, home for Pennsylvanians... This interchange improves travel for the public and businesses, a goal that I m committed to across the State. Governor Tom Wolf PennDOT press release dated 11/17/2017 Source: Tribune-Review article, 11/21/2017 (It will be) the poster child for how to design projects moving forward...this was a special project, and it s going to serve as a model program for the State. Joe Szczur PennDOT District 12 Executive Source: Tribune-Review article, 11/21/2017