Officials hope a new pavement mix will reduce ruts and dips along Sixth and Iowa streets.
A new pavement recipe is getting a trial run this week along two of Lawrence's busiest streets, part of a real-life experiment that could lead to longer lives for new road surfaces in town.
LRM Industries Inc. is using a special mixture -- called BM-2 -- to create 6,368 tons of asphaltic concrete being applied to the city's ongoing repaving project: Sixth Street, from Rockledge Road to Missouri Street; and Iowa Street, from Sixth Street to Yale Road.
Officials hope that the new mix will help reduce the rutting, shoving and cracking problems that have plagued busy city streets in recent years.
``You'll have a nice, smooth street to drive on again,'' Mayor Marty Kennedy said.
The entire project will cost $370,000, of which $150,000 will be picked up by the state. While traditional asphalt would have cost about $30,000 less, officials hope the added cost will pay off down the road.
``For $30,000, if it lasts a couple more years, it's absolutely worth it,'' said Terese Gorman, city engineer. ``We'll see how it works. It's possible we'd use it later on main streets such a Sixth, Iowa and 23rd streets. What we've been using has not been working the greatest.''
The repaving project became necessary after Sixth and Iowa streets showed advanced signs of dilapidation earlier than expected, Gorman said. Ruts formed where tires typically roll, and pavement ``shoved'' up like a loose rug inside a home's front door, particularly where vehicles stop at intersections.
Why the pavement deteriorated so quickly remains a mystery, but officials figure the sand in the pavement had something to do with it. Paving contractors in the area typically use sand from the Kansas River -- small grains with rounded surfaces, thanks to erosion -- in their pavement mixtures.
The new BM-2 mixture -- a.k.a. ``Bituminous Mixture Two'' -- uses less sand in the mixture, and none from the Kansas River. Instead, the company is using ``manufactured sand,'' which has rough edges produced by crushing operations.
The ``angular edges'' should help the asphalt bind better, Gorman said, and therefore reduce the persistent rutting, shoving and cracking of roads under heavy traffic.
``It's always a problem on major roadways like this,'' Gorman said. ``Everybody fights it.''
The repaving project comes seven years after Sixth Street last was resurfaced, and 10 years after Iowa Street received its most recent surface.
The area handles about 30,000 vehicles a day, officials said.
-- Mark Fagan's phone message number is 832-7188. His e-mail address is firstname.lastname@example.org.