Just as an experiment, I drove in from Virginia to the District via the Key Bridge and the Whitehurst Freeway at the height of the rush one morning, and drove in again the next day, this time pretending that the Whitehurst was no more.

My crude exercise sought to measure the congestion we might face if the only bit of expressway on that route into town were demolished in the name of urban planning. So I sat in creeping, crawling stuff along M and K streets NW, adding about 12 minutes to my journey. Twelve minutes of inching and lurching in the morning can feel like forever.

Commuters from Virginia and Maryland who are aghast at the city's proposal to take down the Whitehurst would protest that my test run was deeply flawed, that if the freeway vanishes, there'd be vastly more cars on those Georgetown streets and my delay would be far worse. Quite right.

I should note that when I attended one of the city's information sessions on the proposed deconstruction (the District under Mayor Williams has virtually eliminated traditional public hearings, replacing them with a distressingly effective device that looks like a college seminar, feels like a casual conversation and allows the city craftily to isolate naysayers), suburban commuters and city dwellers seemed almost united on the folly of the concept.

Suburbanites are appalled that the District would even consider taking down a perfectly good stretch of highway without a clear alternate route. Georgetown residents are apoplectic about adding thousands more suburbanites onto their streets each morning.

Then why is removing the Whitehurst the Williams administration's best initiative since bringing baseball to the District?

The city proposes to correct one of its worst mistakes, a classic 1950s effort to circumvent the urban grid so suburbanites could zip in and out of town. Cities across the land tacked expressways onto their edges, happily sacrificing waterfronts to make life easier for those who had fled the city but still commuted to downtown jobs.

But times have changed and cities have evolved. In one metropolis after another, as cities bet their future on creating vibrant urban spaces for residents and visitors alike, cities are reclaiming their shorelines. The old elevated roadways are coming down, replaced by pedestrian promenades and other people magnets.

Georgetown's usable, visible waterfront consists of a single building, Washington Harbour, Arthur Cotton Moore's 1986 fantasy land that attracts huge crowds keen to stroll along the river and enjoy a beverage under the sun. City planners want to open up the rest of the riverfront, now a ratty collection of parking lots and municipal storage space.

The key to unlocking the waterfront is eliminating the shadow and gloom of the Whitehurst's underbelly. But how to calm traffic fears? Planners tried reason: The freeway really doesn't save much time; it's less than a mile long and has traffic lights at both ends. And the Whitehurst never fulfilled its original function, which was to connect the suburbs with urban expressways that, thankfully, were never built.

Such arguments fail, however, against that wonderful, if fleeting, feeling of zipping along the Whitehurst, enjoying the river view. Drivers cherish that minute of speed, even if they face a jam at the end of the road.

Deconstructing the Whitehurst is above all a design challenge. You could tunnel under K Street and get cars downtown that way, but the cost is staggering -- think Boston's Big Dig. You could create a ground-level boulevard as Philadelphia has along its Delaware River front. But then how do you get cars down from Key Bridge to ground level? A straight ramp would block off half of the waterfront. Moore, who has somehow managed to maintain a sense of play in America's most stifling public architecture environment, proposes a cool spiral ramp spinning off the bridge onto a K Street boulevard.

Surely the federal agencies that killed the glass canopy over the Old Patent Office Building courtyard downtown are already stockpiling objections to such an elegant solution. The city should nonetheless charge ahead. Georgetown exists because of its riverfront. It's about time we gave it back to ourselves.

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