Every spring, the shoulders of both gravel and hardtop roads are disked to eliminate secondary ditches, reshape in-slopes, and reclaim gravel—placing it back onto either the gravel shoulders or driving surfaces. This process of "reclaiming" can occasionally elicit negative feedback from the general public, however, as it may take six to eight weeks to complete; in Nicollet County, the primary concern expressed by constituents is often related to the small dirt/sod clumps left behind on the driving surface after the reclaimed material was mixed back into the gravel roads. These clumps can result in a bumpy ride over the following week.
To speed up the reclaiming process and improve smoothness on its gravel roads, Nicollet County Public Works obtained a $20,000 grant through the Local OPERA Program to develop the Rotating Tine Sod Mulcher/Reclaimer (also known as a tiller)—a device that instantly pulverizes the dirt/sod clumps in the reclaimed material while mixing it back in with the existing surface gravel, eliminating bumps on the driving surface.
Careful implementation yields positive results
In practice, the tiller works in tandem with a motor grader to disk, till, and add reclaimed material from the shoulder and in-slope back into the driving surface of the gravel road. Once the motor grader has finished laying out the newly rejuvenated/mixed gravel, it compacts the material using a roller to ensure that it all binds together, thereby creating a durable and long-lasting hardpan surface. For this process to work, certain weather conditions are required: The optimal scenario is 0.3 inches of rain followed by three consecutive dry days. In addition, only one side of the road is addressed each spring, as excessive reclaim may lead to a slippery gravel surface.
Public Works staff acquired one tiller for the 2025 season. Following ideal weather conditions, the device was deployed with the motor grader/disk to successfully reclaim 8 miles of road in a single day—a truly remarkable achievement and a significant victory for both residents and maintenance staff. Just three days later, when a Nicollet County constituent raised concerns about the annual spring reclaiming, he was astonished to learn that the process was already complete.
Success on the horizon
With the 2025 season over, Nicollet County will be using the Rotating Tine Sod Mulcher/Reclaimer on the majority of its gravel roads every year moving forward. In the summer and fall, the device will be used to reshape any remaining shoulders that have incorrect slopes or secondary ditches. With the future addition of two more tillers, the team expects to completely finish reclaiming all of the county’s gravel roads in just three days.