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41 °F Forecast | Road Cams Tuesday, January 25, 2005 Today's News | Classifieds | Autos | Homes | Jobs | Tempo | Health | Community | Home Delivery SECTIONS Home Page Local News Sports Business Obituaries Life Opinion - Politics Tempo AP News Weather Classified Archives Site Map SPECIAL SECTIONS Since We Asked Outdoor Journal Menu Guide How To Guide Wellness Connection Readers' Choice Real Estate Showcase Real Estate Guide Joy Magazine Homelife Magazine Wedding Guide Passport to the Rogue Valley EXTRA Newspaper in Education Personals Movie Times TV Times E The People Volunteer Opportunities Moving to Southern Oregon? MARKETPLACE Find a Car Find a Home Find a Job Classifieds Place an ad eSouthernOregon Automotive Communities Entertainment Publications Recreation Calendar CUSTOMER SERVICE Frequent Questions Advertising Information Home Delivery Employment Contact Us Media Kit Network Affiliate Oregon Road Conditions & Cams Email Story to a Friend March 7, 2004 Jayme Morgan applies a coat of zinc to one of the arches on the Isaac Lee Patterson Bridge, which crosses the Rogue River at Gold Beach. After the bridge is coated, a continuous low-voltage electrical current will be applied to prevent erosion. Mail Tribune / Jim Craven ‘Zincers’ blast bridge into the future By PAUL FATTIG Mail Tribune GOLD BEACH — For husky construction worker Jayme Morgan, success or failure in this job is measured by the width of a gnat’s eyelash. "It all has to be between 15-thousandths and 17-thousandths of an inch," he explained as he took a break as a "zincer" on the 1,932-foot-long Isaac Lee Patterson Bridge, appropriately completed in 1932 over the Rogue River. Looking a bit like an astronaut in his white welding suit and helmet, his job is to coat the restored concrete with a thin skin of protective zinc. The zinc is atomized by 440 volts of electricity and sprayed by air jets onto the concrete with what looks like a welder’s cutting torch. The space-age technique is being used to preserve one of the nation’s historic landmarks within a wave’s crash of the Pacific Ocean. Advertisement "You have to put the zinc on evenly — you put it on too thick, you burn it," explained Morgan, 28, of Gold Beach. Known as impressed-current cathodic protection, the process includes running a low-voltage electrical current through the zinc skin to pull corrosive ions from the steel used to reinforce the concrete, according to Oregon Department of Transportation engineers overseeing the project. "What we’re doing is extending the life of the bridge by 70 to 100 years," said ODOT project engineer David Fletcher, 40, a Medford resident and 1982 graduate of Medford Senior High School. The zinc is a human skin-searing 700 degrees when it hits the concrete, but cools in about five seconds, much like tin foil taken out of a flame, Fletcher said. But the project is more than zinc-skin deep: The massive effort, in addition to covering the concrete’s estimated 330,000-square-foot surface with a thin layer of zinc, includes replacing tons of weakened or cracked concrete and thousands of pieces of corroded rebar. Originally designed by Oregon’s master bridge builder, Conde B. McCullough, the bridge includes seven 230-foot-long arches, each containing a dozen smaller arches. Each end of the bridge is anchored with art deco towers. One of 13 elegant yet efficient bridges built by McCullough along the Oregon Coast, it was the first in the nation employing the prestressing technique designed by French architect Ernest Freyssinet. "This is really a very unique bridge," said Rich Wanke, 57, president of Newport-based Great Western Corp., the subcontractor galvanizing the structure. The general contractor is Hamilton Construction Co., whose late founder helped pour the original concrete. "It’s the first time we went to a post-tensioning type of structure," he said. "The way they did it, after the arches were poured, was jack them apart and pour concrete in the middle. When they let them go, the post tension locked them together." Although the bridge, among a dozen historic coastal spans being restored by ODOT at a cost of about $200 million by 2022, was well designed, some of the concrete poured more than 70 years ago didn’t cure properly, Wanke said. As a result, the amount of concrete needing to be replaced was much higher than expected, he said. "The quantities ran 300 to 700 percent over in some cases," he said. "We normally run a 10- to 12-man crew, and on a lot of this job we ran 30 to try to keep it on schedule." Although the project, which began a little over two years ago, is expected to be completed by September 2005 as planned, it will cost more than the projected $18 million, officials said. But they say it is far cheaper to restore the bridges, coating them with zinc, than to replace them. Since the concrete has to be at least 70 degrees to bond with the zinc, the working area is self-contained and heated by diesel-operated boilers. The containment structure, which is moved periodically, is about 40 feet wide, 60 feet high and 260 feet long. Outside the contained area some 40 feet above the Rogue, visitors are pelted by cold rain carried in the stinging coastal winds. Inside, it’s as warm as your living room. The metallic smell of zinc fills the air where Morgan is working. Workers who don’t wear appropriate safety gear, such as masks, sometimes develop flu-like symptoms from inhaling too much zinc, Wanke said. They shake the symptoms in a few hours, he added. At the other end of the containment area, Josh Rodriguez, 25, of Gold Beach, foreman for the five-member form crew, has been busy removing old concrete. They recently removed a concrete wall some 25 feet long. "We’ve found bits and pieces of things — bottle caps, cigarette packages, old chisels," he said. "People building these forms threw all their garbage down there. "About a hundred years later it’s kind of neat to look at," he added. Especially if it has a dull golden sheen, he said. "We joke about finding gold," he said. "Maybe we’ll find some. They took the river rock and scooped it out without searching through it." Gold Beach’s name came from the fact gold was discovered in the sands in the early 1850s, according to the "Oregon Geographic Names" book. The site drew hundreds of miners to the mouth of the Rogue. A post office was established at the community, initially called Ellensburgh, on March 3, 1863. After being confused with the community of Ellensburg in what was then Washington Territory, it was changed to Gold Beach on March 25, 1890. If Rodriguez found a gold nugget, would he share it with his crew? "Yeah, right," he said with a laugh. Fletcher confirmed that sand and gravel used to form the original concrete was dredged from the river bottom. "We’re chipping out some rocks the size of grapefruits," Fletcher said. "They threw everything in there. "Nowadays, we use up to an inch and a half (sized) rock," he added. "Back then, they just scooped this right out of the river. Nothing was sorted out." The construction crew checks each foot of the old concrete by hitting it with a hammer. "The hammer will have a ring to it until you hit the bad spot," Fletcher said. "When you hit a bad spot, you’ll hear a ‘clunk.’ " In addition, the crew is checking for any metal within a half-inch of the surface, he said, adding that it would be close enough to the zinc to short it out. "We have to patch over those spots to bump out the concrete a little," Fletcher said. When it is completed, the zinc coating will be monitored through computers in Salem, he said. While Fletcher has confidence in today’s techniques, he continues to marvel at the work done seven decades ago. "They had loggers, all sorts of people out here working on it who had never built a bridge before," he said. "But the workmanship came out really good." Reach reporter Paul Fattig at 776-4496 or e-mail him at [email protected] Mail Tribune Home Local News | Sports | Business | Obituaries | Life Opinion - Politics | AP News | Archives | Site Map E Southern Oregon | Classified Copyright © 1997-2005 Mail Tribune. All rights reserved. Privacy Policy | Terms & Conditions Website Feedback ADVERTISERS A D V E R T I S E R S SPECIAL SECTIONS Auto Finder Job Finder Home Finder Joy Magazine Homelife Magazine Tempo Readers' Choice Real Estate Showcase Since We Asked Outdoor Journal Moving to Southern Oregon? Volunteer Opportunities Student Loan Consolidation Conference Calls - $50/Month Home Security Systems Trunks, Footlocker, Trunk, Footlockers