Kudos to Olmsted County Public Works for taking first place in the Inspection and Data Collection category at the National LTAP Build a Better Mousetrap Competition! The county's camera culvert inspection tool (left) also earned second place in Minnesota's Mousetrap contest. First place in our competition went to Rochester for its manhole ring lifter project (right).
"This is a great competition that energizes our team to come up with new and innovative ideas to work more efficiently and safely," says Chris Petree, Rochester director of public works.
This year, Minnesota also had runner-up projects from Crow Wing County and Douglas County. Our thanks to all these agencies for submitting their excellent projects!
The Minnesota competition is sponsored by the Minnesota Local Road Research Board and administered by Minnesota LTAP. Our top two submissions are forwarded to the national competition in June, and recipients in four categories are announced by the National LTAP Association in July/August.
City of Rochester—manhole ring lifter
Problem: The city's Public Works Department rebuilds all manholes (about 500 per year) needing repairs and replacement during street improvement projects. During this process, employees stand on the street and remove concrete rings with jackhammers before manually lifting the broken pieces to street level. This work involves hours of extensive bending and lifting. Additionally, the task of cutting and jackhammering concrete rings exposes crews to silica dust.
Solution: The manhole ring lifter, a hydraulic lifting device that is attached to a crane on a truck, was designed to mechanize the removal of concrete rings. The lifter is first lowered by the crane into the manhole; then, a set of wings are extended to dislodge the ring and lift it to the surface of the street. This device eliminates the need for jackhammering and the manual labor of bending and lifting.
Olmsted County Public Works—360-degree camera culvert inspection
Problem: Olmsted County has over 1,600 centerline culverts that need to be inspected and maintained. To eliminate the need for staff to manually crawl through culverts, the county wanted to build a remote-controlled car similar to MnDOT's HIVE. However, there were some concerns about the HIVE design that the county wanted to improve upon to better serve its needs and systems.
Solution: The county constructed two sleds out of PVC piping, one of which includes floats for culverts containing water. The sleds each hold a 360-degree waterproof camera and lights, and they can be pulled through culverts with reel-mounted fiberglass fish tape. The camera records the whole culvert during the inspection, which allows staff to view any area of concern from multiple viewpoints to analyze if repair is required. Overall, the inspection tool has improved safety for inspectors and removes the need for staff to make decisions in the field because the recorded video can be analyzed at any time.
Crow Wing County Highway Department—standardized mailbox support tool
Problem: With more than 60,000 residents and 26,000 homes in the county, the highway department was encountering mailbox supports being set at varying heights. This caused problems when plowing snow; the wing plow could be used to clear snow under some mailbox supports, but not others.
Solution: The county's maintenance specialist made eight identical four-foot boards for measuring the height of mailbox supports. The boards were distributed internally and to mailbox support contractors working on the county's road projects to ensure that all who install or repair these supports are setting them to the same height. Standardizing heights means that fewer supports are hit by plows, ultimately saving the county money in replacement costs and causing fewer disruptions for residents.
Douglas County Public Works—excavator mower attachment
Problem: Public Works staff were unable to reach high overhanging branches and had to borrow equipment to mow cattails and overgrown willows in wet areas.
Solution: County mechanics used an old diamond mower deck to make a quick attachment that can be used on an excavator. The attachment allows staff to mow and clear unwanted vegetation that impedes visibility at intersections and eliminate overhanging branches on county roadways.
