Harvey County has a lot of bridges; 280 to be exact. Maintaining such infrastructure, especially if said structures need repairs, can be quite a burden. That's why Harvey County Road and Bridge Superintendent Jim Meier has been working closely with MKEC Engineering to develop a plan of action to ease some of the stress regarding those projects.
Currently, MKEC Engineering (as the in-house engineer for Harvey County) routinely inspects all 280 bridges on a two-year rotation, with some of them checked on an annual basis. On top of their inspections, though, the Kansas Department of Transportation will have engineers do random spot checks at various times between the county's own mandated checks.
Those checks by KDOT have led to some poor ratings, forcing certain county bridges to be closed temporarily. One report Meier read for the county commission on Monday rated a bridge as not even being able to support a zero-ton load (and yet it remains standing), while repairs were just completed on another bridge on SW 84th Street — one Meier is projecting while reopen this week — that had been shut down following a KDOT inspection. All of this has forced his department to take a look at how best to address those issues — with the variance of ratings — and plan for the future.
"We're getting to a point where if we're going to be proactive in our approach to replacing things, we need criteria that is consistent and allows us the ability to look at bridges objectively and rate them accordingly," Meier said. "There is a huge grey area that encapsulates the method currently used primarily for bridge load rating."
Following the bridge collapse in Minneapolis, Minnesota, a decade ago, infrastructure issues like bridge maintenance came under greater scrutiny, which is part of the reason Meier come before the county commission on Monday to address continued vigilance and striving for accuracy and consistency in long-term repair plans.
Over the past few years, Meier expressed confidence in the plans the department has put in place to address bridge repairs, but the shuttering of bridges by KDOT led him to question how the county's own inspection and rating system could be improved — especially with some major projects on the upcoming schedule.
"We think our approach has been sound, but we're getting to the point where there are a lot of other structures of great length to be considered," Meier said.
In discussing the issue with MKEC Engineering, one of the main components looked into was finding a better tool to help analyze bridges and the infrastructure needs around Harvey County.
Just through certain criteria (i.e. load rating, traffic volume, bridge length, etc.), MKEC Engineering was able to prioritize the 15 bridges that need work planned soon — with three taken out of consideration having already being addressed either this year or scheduled for the coming year.
Going from 280 bridges to 12 bridges, and making the task less Herculean, was part of what Meier and MKEC Engineering aimed to do. By looking even deeper into structural needs, MKEC Engineering's Karl Svaty noted three of the remaining 12 bridges — due to minimal length and other factors — could easily be replaced with box culverts, which he noted are one-third of the cost of a normal bridge.
One other bridge on that list is already rated at 16 tons and is operating as a one-lane bridge, which led Svaty and MKEC Engineering to recommend continued monitoring for the time being and leaving eight structures that the county needs to take under consideration in the near future.
To determine just what the plan of action should be in regards to each, Svaty said a new form of testing (proof load) could be done to better understand the needs of each structure. Proof load tests are normally used on concrete bridges, but can also be used on steel structures, and utilize strain gauges — with changes in the voltage of the gauges being monitored as loads are transported over the bridge to get an idea of what it can handle.
"If everything's working, it's a very linear function and it's very easy to come up with that number," Svaty said.
Ratings can change based on the results and Svaty noted the tests are a good tool to confirm if any potential bridge repair is one the county should spend money on — or if it will hold up for a few more years.
Exact costs are not known at this time, but Svaty was adamant about its affordability — especially given that costs have continued to come down over the years and the cheapest replacement project for the bridges that would be tested is projected at $275,000.
"We're not telling you that you have to spend any money today to do anything, but we've offered a way of kind of looking at these 12 bridges and what you might do," Svaty said.
Having the option, and opportunity for the commission to defray costs, is something Harvey County Administrator Anthony Swartzendruber said could be of great benefit — especially as the process pares down the infrastructure needs to those of highest priority.
"I think this is a great tool you have at your disposal now for moving forward," Swartzendruber said. "It has the opportunity to save us a significant amount of money."
No action was needed on Monday, but Swartzendruber noted he is working on a formal proposal on the new bridge rating initiative to bring before the commission in the near future.
With these new priorities and testing plans being looked into, Meier believes the benefit to the county would be two-fold.
"If we can better analyze with more reliable results and be able to bump that bridge back on the time scale, it's not only about saving money," Meier said, "it's about having a better analysis."