Regarding the Beltway, Answer Man Straightens Out a Few Kinks and Curves

A serpentine stretch of the Beltway between Georgia Avenue and Rockville Pike poses a challenge for drivers.
A serpentine stretch of the Beltway between Georgia Avenue and Rockville Pike poses a challenge for drivers. (By James M. Thresher -- The Washington Post)
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By John Kelly
Sunday, September 14, 2008

Why does the Beltway between Georgia Avenue and Rockville Pike have so many curves? If you look at a map it doesn't appear that it would have been difficult to make the section more straight.

-- Bob Fowler, Greenbelt

Answer Man has always liked a story told about the Italian renaissance artist Giotto di Bondone. Giotto was once visited by an emissary from the pope and asked to provide an example of his work to win a commission. The artist dipped his brush in paint and drew a perfect circle.

We marvel at such anecdotes because we know how hard it is to achieve perfection, especially without the aid of the mechanical devices that have made perfection nearly attainable. And yet even armed with those tools -- compasses, quadrants, theodolites -- the engineers who designed Washington's Beltway didn't produce a perfect circle. Nowhere is the circle more problematical than in Montgomery County between Silver Spring and Bethesda, where the highway skitters to and fro like a drunk on roller skates.

The 1950 National Capital Park and Planning master plan was the first serious suggestion that Washington be encircled by a ring road, directing traffic around the city rather than through it. Except for dealing with the tricky mud and sand near Alexandria, the 22-mile section of the road in sparsely populated Virginia was relatively easy to construct. Maryland was another story. The suburbs were more populous there, and designers had to thread through existing developments. In Montgomery County, the engineers faced a choice: They could demolish hundreds of homes in Kensington or they could put the highway in a swath of mercifully undeveloped land. Of course, that land was undeveloped for a reason: It was Rock Creek Park.

Nature lovers, including the head of the National Park Service, opposed that alignment, but a federal judge approved construction -- so long as the Beltway there was a parkway, not a highway.

Almost immediately, citizens groups raised objections. Legend has it that certain wealthy, influential people were able to push the Beltway away from their back yards. But when historian Jeremy Korr studied the issue for his PhD thesis, "Washington's Main Street: Consensus and Conflict on the Capital Beltway, 1952-2001," he wasn't able to find any single smoking gun -- or super-NIMBY -- responsible for the curves. Rather, he wrote, the curves were "the cumulative result of repeated political interventions into what area engineers had previously considered a relatively apolitical process."

Engineers had to follow the park's contours without obstructing Rock Creek itself, all the while being buffeted by orders from above to make changes -- as many as four a week, according to Korr. The result was the sinuous route commuters love to hate.

William Shook, an engineer who retired from the Maryland State Highway Administration in 1980, was one of the Beltway's designers. He personally walked much of the original line, hiking through brush, descending into ravines, fording streams. He says of that section of roadway: "I know that if we could have built it strictly adhering to the engineering desires of the designers, there definitely would not have been as tight a curve as you have today."

While the section was first constructed as a parkway -- no trucks allowed, a 50 mph speed limit -- by the time the entire Beltway was completed in 1964, the so-called "roller coaster" had been rebuilt to meet interstate standards. But they couldn't get all the kinks out.

By 1966, that area was accounting for a quarter of the accidents on Maryland's portion of the Beltway, though it makes up just 10 percent of the total mileage. Since then, its curves have been straightened slightly and other improvements have been made to make it safer.

Bill Shook still drives on the Beltway, but he said: "My feeling today is I don't enjoy it near as much. I'm proud I had a lot to do with it, but then the Beltway has greatly changed."

The whole region has. A ribbon of fresh concrete -- like the Beltway in 1964 -- doesn't alleviate traffic anymore; it just lures more vehicles.

"I used to enjoy driving a car anywhere," Bill said. "Today it's got to the point where driving a car is stressful, when you get down to it. You don't realize how stressful it is until you get home, collapse in a chair and realize you've been pretty well stressed-out."

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