ST. LOUIS (AP) – The $380 million project to redevelop the Gateway Arch grounds and the area of downtown St. Louis around the Arch is getting a boost from an unexpected cost savings.

The St. Louis Post-Dispatch reports that a “lid” to be built over Interstate 70 to better connect the Arch to the rest of downtown was originally expected to cost $47 million. Construction starts this summer.

But engineers discovered that concrete walls that hold the earth away from the highway don’t need to be torn out and rebuilt after all. That saves $11 million.

That cost-saving will allow for redevelopment of Leonor K. Sullivan Boulevard, the street that runs in front of the Arch. Plans call for raising the street 2 .5 feet and adding bicycle and pedestrian paths.

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