Interstate 83 (I-83) Exit 4 is an existing diamond
configuration interchange with signals located at the ramp intersections with
PA 851. Due to the growth of the Shrewsbury area, congestion is experienced at
the interchange during peak periods, and traffic exiting I-83 northbound and
southbound backs up onto I-83. Two options were developed for the reconstruction
of the interchange, the tight diamond interchange and the diverging diamond
interchange. Following option development
and public involvement, including a public meeting held on March 30, 2016, the
diverging diamond interchange was selected to advance into final design.
Diamond Interchange (DDI) configuration will have two eastbound and two
westbound lanes on PA 851 and utilize signalized ramp intersections to cross
traffic over to the left side of the roadway with a return to the right side
within the interchange limits. It will improve traffic flow,
particularly for left turns, to and from I-83. The design will include the
replacement of the bridges that carry I-83 over PA 851 with two-span
structures that will accommodate the additional lanes on PA 851 as well as
possible future widening of I-83. The Deer Creek culvert under the interchange
will be replaced. Also included is the lengthening of the I-83 northbound and
southbound on and off interchange ramps. Two lanes of traffic in each direction
will be maintained on I-83 throughout the majority of construction.
Please refer to the
resource documents on the right for more information.