Although traffic will be allowed to continue using the Main Street Viaduct until July 23 - even though signs already in place indicate that the span will close on Monday - it is not too early for motorists to consider the alternate routes they will use during the approximately three months that a detour will be in effect.

The official detour tied to new-viaduct construction will use the Picklegate Crossing, Hansen Avenue and Route 356, but no doubt many motorists will choose to use other routes that more conveniently meet their needs. It would be foolhardy not to give the detour serious consideration prior to being confronted with it.

Truck traffic will have few, if any, alternatives to Picklegate-Hansen-Route 356 unless that traffic can find a way to avoid Butler completely. Cars and other passenger vehicles will have more options, if drivers choose to pursue them.

It is conceivable that some residential neighborhoods will experience higher-than-normal traffic volumes for the next three months, and that will require parents to be more watchful in regard to the safety of their children.

An average of 22,000 vehicles currently use the Main Street span, so the closing of the viaduct is likely to produce a number of challenges requiring patience and understanding. The situation can be made more tolerable and less stressful if pre-planning takes place, both from the standpoint of new routes or use of the detour and the time allotted to get to a destination.

The new viaduct is being built in two sections, each with two lanes and separated by a barrier. The northbound side will be finished first, with both northbound and southbound traffic scheduled to make use of that section until about Nov. 17, 2006, when the 1,232-foot-long span is targeted for completion.

Not including interstate highways, the new viaduct will be the largest bridge built in the state Department of Transportation's District 10, which encompasses Butler, Armstrong, Clarion, Indiana and Jefferson counties. It will provide a modern entrance to the southern end of the downtown, in contrast with the current deteriorated span, which was built in 1917 and which PennDOT is correct in describing as a bridge that "doesn't have much more life." The old span is expected to be torn down soon after being closed.

Commendably, the city's Shade Tree Commission and other city officials have already discussed beaufication efforts tied to the bridge project. A welcome sign, concrete planters at each end of the new bridge, and flower baskets are among what already is under consideration.

Officials hope to have the beautification plans tied to the new bridge drawn up by the time construction is completed.

Also enhancing the city will be the associated new and reconstructed roadway that will be part of the overall project. PennDOT lists the overall project length as 3,500 feet.

For many motorists, the upcoming detour isn't going to be a pleasant experience. But they should consider the bright side of what lies ahead: The deck of the new bridge is expected to last for 30 years before needing replaced, and the new span is expected to last 100 years.

In those terms, three months of inconvenience can't be that bad.