JOHN DAY — For years, the city of John Day has tried to keep commercial vehicles from using the Third Avenue Bridge over Canyon Creek with a sign the reads “No Trucks” and another that reads “Weight Limit 15 Tons.”

But that doesn’t mean the span is in imminent danger of collapsing under the strain of a fully loaded 18-wheeler. As it turns out, the bridge can handle considerably more weight than its posted limit.

In fact, according to the most recent Oregon Department of Transportation safety inspection report on the bridge, it is rated to support up to 67 tons, or 134,000 pounds — more than four times the posted limit.

What’s going on here?

According to City Manager Nick Green, the “Weight Limit 15 Tons” sign is part of a strategy to save the city — and local taxpayers — money on bridge repairs.

“The Public Works Department put that sign up there to discourage commercial vehicles from using that bridge,” he told the newspaper. “The city’s preference is for them to use Bridge Street.”

Sometimes, Green explained, heavily laden trucks headed for the Grant County Fairgrounds will use Third Avenue, which puts a certain amount of wear and tear on the city-owned Third Avenue Bridge. If they take Bridge Street instead, the big rigs don’t have to cross any bridges to reach the fairgrounds.

The issue came to light after the Blue Mountain Eagle published a letter to the editor from local resident Jon Meiling in its Feb. 23 edition, under the headline “City Leaders Ignore Bridge Safety Issue.”

Meiling expressed concern that the city was failing to enforce the commercial vehicle ban, creating the possibility that the bridge could fall down under the weight of a fully loaded tractor-trailer rig.

“The Third Avenue Bridge has a sign that reads No Trucks and a 30,000-pound weight limit. Yet the city officials allow overweight trucks to cross that bridge on a daily basis with blatant disregard for the safety of the citizens of John Day,” he wrote.

“The infrastructure of that bridge cannot carry an 80,000-pound load, let alone a 100,000-pound load.”

Green responded to Meiling in an email, which he shared with City Council members and the Eagle, noting that the span’s 67-ton load rating is more than adequate for the heavyweight trucks Meiling worries about in his letter.

“The bridge is safe. It can certainly handle those loads,” Green wrote. “We post it at 15 tons to encourage larger trucks to re-route, but we’re not in a position to cite trucks that violate that rule, and violation of the rule does not pose a safety hazard to the bridge or our residents.”

In the email, Green points out that an ODOT inspection report from last August, which he also shared with the newspaper, rates the condition of the bridge’s deck and substructure as good (7 on a 10-point scale) and its superstructure as satisfactory (6 out of 10).

The report goes on to state that the prestressed concrete bridge, built in 1989, suffered some damage that required patching in 2014 and that the abutments need to be monitored for scouring by gravel in the creekbed.

Apparently, the city strategy to reduce wear on the bridge by rerouting heavy trucks is as old as the bridge itself. Green said former Public Works Director Dave Holland told him the “Weight Limit 15 Tons” sign was installed at the same time as the bridge.

In response to an inquiry from the Eagle, an ODOT official confirmed that the 67-ton load rating for the bridge is still in effect, so it has “plenty of capacity for traditional legal vehicles.”

Jon Rooper, a senior load rating engineer with the state agency’s bridge engineering section, added that, as the bridge’s owner, the city of John Day is well within its rights to post a lower weight limit than the rating allows.

“There is no rule that says they cannot,” Rooper said. “In fact, we have many local agencies in the state that post bridges for less load than needed in order to preserve historic structures or to prevent truck traffic from using a specific route.”