An ounce of prevention can be worth a pound of cure, and in this case, we're talking about tons of prevention, in the form of huge stone piers that held up the Pennsylvania Turnpike's old Allegheny River Bridge.

The bridge is being replaced with twin spans that each will carry three lanes of turnpike traffic from Plum to Harmar, over rustic Fourteen Mile Island, uninhabited wilderness just 14 miles from the Point that's accessible only by boat. On Tuesday, the section of the bridge over the main river channel was imploded, and the portion over the back channel will be demolished later this month.

The turnpike agreed to hold off on downing the piers while Allegheny County considers whether to preserve them for a future use, such as a bike trail crossing. Two other replacement spans over the Allegheny -- the Hulton Bridge and the Freeport Bridge -- both will include pedestrian and bike paths, but the county shouldn't be too quick to dismiss the need for another walkable span in the long run.

It has not been all that long since Western Pennsylvanians overlooked the recreational and economic development potential of their riverbanks. Thirty years ago, anyone who would have suggested the possibility of bicycling from Pittsburgh to the Potomac in the nation's capital would have been considered a few gears short of a 10-speed. Now, with an agreement apparently close to being worked out with Sandcastle Waterpark on the final, one-mile stretch, that's a reality.

Who knows what the future might hold for the piers, including the possibility of pedestrian and bike access to pristine spots on the island below?

Naturally, the county must consider any ramifications of taking ownership of the piers -- liability in the case of future problems, maintenance of the pylons themselves and the safety lighting affixed to them, for example. But unless any associated costs are unreasonable, it's worth holding on to these fixtures.

County Council should act with its eyes on the future.

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