The first to spot signs of trou­ble in our na­tion’s in­fra­struc­ture

The Washington Post Sunday - - METRO - ROBERT THOM­SON Dr. Grid­lock also ap­pears Thurs­day in Lo­cal Liv­ing. Com­ments and ques­tions are welcome and may be used in a col­umn, along with the writer’s name and home com­mu­nity. Write Dr. Grid­lock at The Washington Post, 1150 15th St. NW, Washington, D.

While Congress dithers over what to do about the fu­ture of Amer­ica’s highways, peo­ple like Keith Vaughn are out try­ing to pre­serve what we’ve got a lit­tle longer. He’s a bridge in­spec­tor for the Mary­land State High­way Ad­min­is­tra­tion, an in­spec­tion team leader for two decades.

Mary­land has 5,243 bridges, and the SHA is re­spon­si­ble for main­tain­ing 2,570 of them. Vaughn’s ter­ri­tory is south­ern Mary­land, and he took me along for a checkup on the bridge that car­ries Al­ter­nate Route 1 traf­fic over the North­east Branch of the Ana­cos­tia River.

This bridge isn’t par­tic­u­larly high, or long, or at­trac­tive. But it’s got a ter­rific health plan, thanks to peo­ple like Vaughn. Ev­ery two years, the SHA sends out a crew to give it a top-to­bot­tom phys­i­cal.

The road sur­face, which sup­ports about 15,000 ve­hi­cles daily, is ex­am­ined for wear and tear. The steel gird­ers and riv­ets on the un­der­side are probed for peel­ing paint and rust. The con­crete foun­da­tions be­low the wa­ter’s sur­face are checked for ev­i­dence of de­te­ri­o­ra­tion.

The SHA has a list of 69 bridges con­sid­ered “struc­turally de­fi­cient,” which means its Of­fice of Struc­tures be­gins de­sign­ing fixes, and the work be­comes el­i­gi­ble for fed­eral funds. The most com­mon cause of con­cern is the bridge deck.

The twin-span bridge over the North­east Branch in Prince Ge­orge’s County isn’t in that cat­e­gory. Built in 1955, it got a new deck in 1999, and was it last in­spected in fall 2013.

To start, Vaughn walked the side­walk, check­ing the road’s con­crete, the guard rails, the nearby veg­e­ta­tion and the bridge ex­pan­sion joints. The worst thing we saw was dirt that had got­ten into the lit­tle rut that’s part of the ex­pan­sion joint, some­thing that’s easily cleared out.

Cracks some­times ap­pear in the con­crete, but that’s not nec­es­sar­ily a prob­lem. It de­pends on the char­ac­ter­is­tics. Your tax dol­lars are pay­ing for an ex­pe­ri­enced guy such as Vaughn to rec­og­nize the dif­fer­ences.

While he did this sur­face re­view, a crew shut a north­bound lane to po­si­tion a “snooper truck.” It’s like a util­ity com­pany bucket truck, but more ver­sa­tile. The twop­er­son bucket is at­tached to a long, ex­tend­able arm that swings it over the river and un­der the bridge.

This in­volves as many ups and downs as a theme-park ride. But Vaughn looked com­fort­able in his mov­able work space sus­pended be­tween the river and the bridge beams. He low­ered and raised the bucket to check paint, riv­ets, gird­ers and con­crete sup­ports. Af­ter a sec­tion be­tween beams was re­viewed, Vaughn pressed the levers that low­ered the bucket, shifted po­si­tion and rose up again to ex­am­ine another sec­tion.

All the ups and downs held my at­ten­tion. The shal­low river was a com­fort­able dis­tance be­low, but the beams and the bridge deck were re­ally close. Vaughn’s ex­pe­ri­ence kept us from closer en­coun­ters with steel.

He told me that this type of in­spec­tion is nor­mally a twop­er­son job, with him do­ing the in­spect­ing and another SHA staffer op­er­at­ing the bucket. “I guess you’re think­ing, ‘Now he tells me,’ ” Vaughn said.

From his point of view, there’s not much to worry about with this struc­ture. He took out a pick of the type you might see a prospec­tor swing to take an ore sam­ple, but he used it to re­veal the ex­tent of peel­ing paint, rust or crum­bling con­crete.

If he found any­thing se­ri­ous, he could call in to an engi­neer re­spon­si­ble for the bridge. In an ex­treme case, a bridge could be shut and an emer­gency re­pair or­dered. But there’s noth­ing more than a few flesh wounds here, which can be easily cured with fol­low-up main­te­nance.

Over the years, these in­spec­tions build up quite a case file on even a small bridge such as this one. Vaughn is sup­ple­ment­ing the file by paus­ing to jot down notes and take photos.

“In­for­ma­tion is good,” he said of the new chap­ter he was adding to the bridge’s life story.

Not all the in­for­ma­tion is vis­ual.

He tapped his ham­mer against steel and lis­tened. He might also need to de­tect the smell of gas if there were a prob­lem with a util­ity line.

The bucket swayed. Like Vaughn, I was in a safety har­ness clamped to the bucket.

But this sway­ing, caused by the mo­tion of the snooper arm, the truck above us and the traf­fic vi­bra­tion, was a nearly con­stant pres­ence. Although Vaughn has made a ca­reer of this, he said he still no­tices the mo­tion.

I won­der if there was any par­tic­u­lar bridge job that was mem­o­rable to him. He im­me­di­ately named the Gov. Thomas John­son span over the Patux­ent River. It’s two lanes wide, 11/2 miles long and about 135 feet high.

I’m sure the view from a snooper truck would be spec­tac­u­lar, but that’s one tour I’d pass on.

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