Interstate 84 through Pike County must be replaced, PennDOT has determined.

Interstate 84 through Pike County must be replaced, PennDOT has determined.
The largest project in the six-county District #4 in many years, approximately $400 million is expected to be spent over the next five or six years.
Work is to start in the spring of 2014, said James May, District #4 spokesman. Work is to be done in fiive sections, one at a time, reducing travel to one lane.
In the end, motorists will be traveling on a completely new interstate road. It will still be I-84, but not unlike a house sporting a brand new roof- only in this case its a whole new foundation.

*** Chemical reaction

May stated that the project became necessary due to gradual deterioration from below. Unlike a surface pothole created by the annual freeze and thaw cycle, this problem goes back to high school chemistry class, he said.
The problem is an alkali-silica reaction in the concrete. When the interstate was built in the early 1970's, a new type of cement was used. Concrete is made up of cement and stones. What was not realized at the time, the new cement reacts chemically with certain types of stone. The stone in question came from a local quarry. The rock used for the western end of I-84 in Lackawanna County came from a different quarry, which did not cause the same reaction.
Coupled with rain water as a catalyst, over the years a gel forms around the pebbles in the cement. In the 1990's paving was applied to try and keep the water out, but the long term solution, May said, was "to rip it out and re-lay the whole thing."
The damage from underneath shows up on top as spider-cracking and areas that fall in, May said. The driving surface has become rough.

*** Five phases

• The first phase is to rebuild a 30 mile section of the westbound lanes of Interstate 84 in Pike County from Milford (Ext 46) to the New York Line. May stated that the more eastern part of the interstate is the worst, as it was built first.
Drivers will experience one lane traffic in Pennsylvania and more while crossing the border: New York is planning to do bridge work over the Delaware River around the same time this project starts. May stated that PennDOT will coordinate with their New York counterpart, saying it is better for traffic flow and safety if they have "one long work zone" (shared by both states) than a couple smaller ones.
Each of the five sections will cost an estimated $75 million. The project will be ready for bidding in the fall of 2013.
PennDOT will totally replace the east- and westbound bridges over Route 6 at Matamoras; the two bridge decks over Foster Hill Road will be replaced; two more decks will be replaced over Cummins Hill Road; and the bridges over Saw Hill Creek will be replaced from beam to deck.
• Section two, slated for work between 2015 and 2017, is in the design phase. It will start at Exit 34, Lords Valley/Dingmans Ferry, and end at mile marker 40.
• Section three will start at mile marker 18 near Greentown/Lake Wallenpaupack and go to Exit 26, Tafton/Promised Land State Park.
• Section four will replace pavement from mile marker 40 to Milford, Exit 46.
• Section five will extend from Exit 26, Tafton/Promised Land State Park, to Lord's Valley, Exit 34.
The timeline and details of the last three phases depend on funding.
Asked if this time they would choose stone from a different quarry, May said that since the I-84 was first constructed, a solution was found to add fly ash to the cement and counteract the chemical reaction.
If nothing was done, May said, "the interstate would eventually go back to dirt."
Meanwhile, PennDOT's Pike County office must continue to maintain the interstate while waiting for the complete replacement. In August the Pike County crew will be performing a $400,000 maintenance project.
Although unfortunate that the maintenance will later be ripped up, May likened it to patching the house roof to keep out the leaks while waiting to be able to replace the whole thing.
Another project affecting I-84 is almost done. The new bridge on Route 402 in Blooming Grove Township is scheduled to be done in September 2013.