ST. LOUIS — As sure as the first hint of sunlight glances off the stainless steel arch, the day breaking over the St. Louis riverfront is bound to capture Capt. Arthur F. Denkmann Jr. meeting his appointed rounds.
A field gauge reader for the U.S. Army Corps of Engineers, Denkmann has measured the depth of the river as it flows past the base of the Gateway Arch for 45 years.
Back in the day, the corps and various other agencies monitoring the ebb and flow of the Mississippi, the Missouri, the Ohio and the rest of the tributaries comprising the Western Rivers system paid hundreds of people to do what Denkmann, 70, has done nearly every morning since Oct. 1, 1965.
Now, with satellite-guided technology capable of measuring depth far more accurately than the human eye, the 18 readers who check the 30 remaining manual gauges on the Mississippi are relegated to auxiliary status.
"They are just there to verify the data" spit out by the 120 automated sensors along the length of the river, said corps spokesman Jim Taylor.
One of those automated sensors was positioned on the Eads Bridge, within clear sight as Denkmann went about his business.
"I'm a dinosaur," he said, casting an eye toward the electronic gauge. "Obsolete."
But he said he believes the job will never fade away, saying that the service traces its roots to the administration of President Andrew Jackson.
"In my conversations with the powers that be, (the job) can never be shelved or put aside no matter how developed technology gets," Denkmann said. "In a national emergency, if all the communications systems go down, we're still going to be there."
The title, captain, is separate from Denkmann's part-time position with the corps.
It's a vestige of the days when he and his father, longtime St. Louis dry cleaner Arthur Denkmann Sr., plied the river on the Mississippi Belle, the tour boat they operated from 1960 to 1972. Father and son were shepherding a party of sightseers when the final piece of the Arch was lifted into place in 1965.
A red bandanna around the neck and, as often as not, a bush hat perched on his head, Denkmann begins his rounds about 8 a.m. He visually measures the metal-plated staff gauge that extends into the river from the base of the Arch's floodwall.
"Looks like we're at about 20.4 this morning," he said. A river gauge is delineated like a surveyor's measure — 10 inches to the foot.
Denkmann has seen the depth as low as four feet and as high as 50.
The latter, of course, occurred during the Great Flood of 1993. That summer saw Denkmann taking his measure of the river every six hours.
Each visit required him to stake out a position further up the incline descending from the Arch, taking a measure of the river through binoculars as the crest crept incrementally over the flood wall (31 feet) and then topped the gauge (45 feet) attached to a utility pole on Leonor K. Sullivan Boulevard.
The depths of the '93 flood are registered in Denkmann's meticulously kept log book.
On Oct. 5, 2010, the log will show the Mississippi River flowed at a depth of 20.4 feet at St. Louis.
With the information immortalized in his book, Denkmann strolled to the bracket holding the yellow sign that has long provided the depth of the river to passing tug and riverboat captains. He dutifully switched out the numbers.
Denkmann cannot say for sure whether captains still pay attention to a 6-foot sign, which is partly hidden from river traffic by a heliport to the north and the riverboats moored to the south.
With data from the automated sensors flowing electronically into the wheelhouses of modern watercraft, the odds are probably not.
After updating the numbers, he moved along to the next stop on his daily odyssey along the river that has been a constant companion since a boyhood spent in north St. Louis. For Denkmann, reading the gauges was once a family affair.
He worked the gauge downtown before heading to his day job in the construction industry.
His wife, Deloris Denkmann, captured the readings just south of the Jefferson Barracks Bridge.
After Deloris' death in 1995, Denkmann — who has since remarried — assumed the duty at both locations.
To Denkmann, the two-track road overlooking the Jefferson Barracks Bridge, where he takes the manual reading off a corps gauge mounted on an off-shore barge piling, is nothing less than "God's Country."
Deer, raccoon, beaver and "all sorts of other critters" frequent the spot.
"The only place I've ever seen a blue bird, the Missouri state bird," he marveled.
The bucolic, as Denkmann discovered, can also be treacherous.
Last winter, Denkmann slipped on an icy patch, breaking his leg as he moved through the brush seeking a better angle to train his binoculars on the gauge.
The leg in a cast, Denkmann was back on the job within days.
Denkmann reports that his wife, Debbie, "liked to have killed me."
The modest stipend Denkmann receives from the corps doesn't cover much beyond the cost of the fuel of the round trip from his home in south St. Louis County to downtown and back (the Jefferson Barracks Bridge being a couple of miles away) each day.
Gazing over the current sweeping below the JB Bridge one morning, he spread crumbled day-old bread on the ground, a parting gift to the "eyes that are probably watching us right now from those woods back there."
His workday over, a dinosaur far from extinct hopped into his sport utility vehicle and headed for home.