At first glance, it begged for a second glance. “Divers Needed.” Probably a typographical error… a gremlin robbing the word driver of its first “r.”
Accompanying the announcement was a photo of a goat (it looked more like a dog with spiked ears), knee deep in water, wearing a SCUBA tank and goggles. Upon further review, the job invitation indeed asked for certified divers to volunteer for ITD’s underwater bridge inspection team.
The department has conducted in-house – well, internal – underwater inspections for nearly two decades, opting to use its own employees to look for submerged bridge deficiencies rather than contract with outside divers. Fewer than half of the state transportation departments have their own dive teams, explains Kathleen Slinger, ITD bridge inspection engineer.
ITD’s underwater inspection program began in about 1988, said Doug Chase, a charter member of the team. He was a traffic engineer in District 6 before becoming state bridge maintenance engineer in 1988. He participated in underwater inspections about three years, until he became assistant state maintenance engineer in 1992.
“It’s difficult because of the regular job demands,” he explains. “It takes a supervisor who will allow employees time away from their regular activities to help with the bridge inspections.”
Divers receive no additional compensation for slipping into water that often is cold, murky and swift flowing. Conditions usually are inhospitable, by recreational diving standards. Because visibility usually is limited (at best), divers often have to rub noses with bridge members and inspect for cracks or exposed rebar using the Braille method.
“It’s not easy work,” Slinger emphasizes. “You don’t have to be a Lance Armstrong” – a strong athlete with impeccable physique. More important is familiarity with safe underwater techniques and a rudimentary knowledge of bridge standards.
None of the half-dozen ITD employees who volunteer for occasional underwater duty are bridge inspectors in their day jobs. They represent a cross-section of ITD expertise. But all must take a two-week training course in bridge inspection and understand National Bridge Inspection Standards before exploring the depths of Idaho rivers and lakes.
“We’re looking for people who can give some level of commitment to the program because we have to provide the training,” Slinger said.
Divers draw their regular ITD salary, receive typical travel-related expenses and are compensated $100 per day for the use of their equipment. It’s a frugal but very effective way to inspect the 324 bridges in Idaho. Divers inspect both state-owned bridges and “off-system” structures that are maintained by local jurisdictions.
Their objective is to identify potential problems with scouring (bridge piers and piles exposed by underwater erosion), material damage to the piers, exposed rebar or bridge members, debris that becomes lodged on the piers and piles. Scours can be intermittent, present on one inspection and refilled on another, Slinger explains.
Inspectors also look for structural damage caused by collisions (which is very rare in Idaho) and possible seismic damage (possible but extremely uncommon).
Some of the Snake River bridges, of which there are many across southern and central Idaho, are among the most challenging because visibility usually is poor and the current swift. The deepest dives are required at Lake Coeur d’Alene’s Blue Creek Bay on Interstate 90; inspectors reach depths of about 100 feet, Slinger says.
The most time-consuming inspections are of Long Bridge – side-by-side vehicle/pedestrian bridges over the Pend Oreille River south of Sandpoint. The bridges are more than a mile long (5,900 feet), have spans of 30-35 feet and approximately 1,400 piles, each of which must be inspected separately.
If the opportunity to literally immerse yourself in your work sounds intriguing, check the following requirements and contact Slinger (334-8407) or Drake (745-5609):