PITTSBURGH (KDKA) – Two major ramps that carry drivers out of downtown to points south and east are closing for four and a half months.

The Sports and Exhibition Authority’s Cap Project to build a park over the Crosstown Expressway needs one more vital support.

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“So the pier is literally right next to the on ramp from Seventh and Bedford avenues,” says the Assistant Executive for Construction of Penndot District 11, Jason Zang, P.E.

The Bedford Avenue ramp carries traffic to the Liberty Bridge, Boulevard of the Allies and Parkway East. It is used by daily commuters who park near the PPG Arena and those who attend events at the arena.

The Seventh Avenue ramp brings traffic from Grant Street between the UPMC Tower and the Federal Court House and to those same destinations.

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The closures will be made just before dawn on Saturday and Zang says will be with us for “140 calendar days.” That puts the reopening around May 23.

Once the closings are in place leaving the arena, the detour will take you downtown. Zang says you’ll use the Seventh Avenue side of the Bedford ramp to Grant Street: “You can go to Grant Street, make a left onto Grant Street and get right on the Parkway East or West.”

The two ramps carry a combined 6,600 drivers a day and all that traffic will be funneled to Grant Street. Zang says, “We will have police officers stationed just for the first few days, just until we get a good handle on how bad the traffic is.”

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The immediate impact of the closings will be felt after Sunday’s Penguins game against the Florida Panthers, and during the Monday afternoon rush hour. Again, the closures will be in effect until late May.