Pons asinorum

2011-10-09 19:58:32

Friday evening, as I drove home from school, I saw that the traffic was backed up on I-265 west-bound, from Grant Line Road to the west. This was at about 6:20 p.m. I wondered if it was rush hour congestion, or if there was an accident. Actually, it was unusual for there to be that kind of congestion there, especially at that time in the evening on a Friday. But I soon found out what the problem was---when I turned on the television to catch the 6:30 network news, I saw a headline crawl saying the Sherman-Minton Bridge had been closed. The congestion I saw was because traffic was being diverted away from I-64 north of the bridge (the bridge carries that interstate across the Ohio River). The bridge was closed because of the discovery of dangerous cracks in load-bearing structural members. Apparently, the cracks were scary enough that the bridge was closed during rush hour (at about 5 p.m.), by order of Mitch Daniels, Governor of Indiana (Indiana is responsible for this bridge). It is expected that the bridge will be closed for months; it may need to be replaced.

The bridge normally carries 90,000 vehicles across the Ohio River every day, about 30% of the traffic across the river; this traffic will have to use either the Kennedy Bridge (which carries I-65 across the Ohio River), or the Clark Memorial Bridge (a smaller bridge for surface traffic near the Kennedy Bridge). The Kennedy Bridge is already operating above design capacity; it was due for an inspection but this will be postponed. So extremely long delays in the commute are anticipated tomorrow morning. I am very glad I live and work on the same side of the river; most of my trips to Louisville are on the weekend and are discretionary (I've crossed the river three times this weekend without any trouble).

Some locals are suspicious about the bridge closure. There's been an effort to build new bridges in the Louisville area, which are widely regarded as badly needed, but political pressure has stalled these projects for as long as I have lived in these parts (more than 17 years). So the suggestion has arisen that shutting down the Sherman-Minton Bridge is a ploy to force new bridges to be built. I'm skeptical, of course; I posted a comment on a discussion thread on facebook to make fun of this suggestion: "It is reported that al Qaeda is seeking to target tunnels and bridges---we must confront the possibility that terrorists have been planting fatigue cracks in load-bearing structural members in bridges across the country!" The truth of the matter is that a serious infrastructure issue has been disregarded by the city for a long time. The foolishness of the city in its inability to make progress on this problem brought an odd phrase from mathematics to mind this morning: pons asinorum ("bridge of fools," literally "bridge of asses"). (This refers to the elementary theorem from Euclid's Elements that says that the base angles of an isosceles triangle are equal. Apparently, this was the point where students would first have trouble when studying their geometry.)

An update: (2011-10-09) It turns out that the bridge can be repaired; this will take about 6 months. This is good news---it would have taken two or three years to replace the bridge. But last week, a colleague of mine complained on Facebook: Is Louisville the possibility city? It is, unless you want to build a bridge, have a theme park, have a full orchestra, etc. (He was referring to the bankruptcy of the Louisville Orchestra as well as the local Six Flags theme park; both are not in operation, and it is unclear if or when they will be back in business.) The locals need to consider Portland, Oregon---a river town roughly twice the size of Louisville, but with a national reputation for land use planning, mass transit, cultural resources, green architecture, parks and quality of life. I find myself thinking that there is a personal cost to living in Louisville; after 25 years, I still feel like I'm in exile from the Northwest.