Wisconsin Trackout Control BMPs
The Wisconsin Department of Natural Resources (DNR) administers the Clean Water Act and issues stormwater permits to contractors, municipalities, and industrial sites. Applications for stormwater permits are completed online, and various resources are provided to inform the construction and post-construction Best Management Practices (BMPs) that will be used. Construction projects that apply for the WPDES Permit No. WI-S067831 must submit an Erosion Control & Storm Water Management Plan. The DNR has developed erosion and sediment control technical standards to assist landowners and contractors in developing a construction site erosion control plan.
Construction Site Erosion & Sediment Control Standards
The DNR's technical standards inform contractors about the techniques proven to meet the requirements of the Clean Water Act. The Standards include various BMPs for preventing erosion, including specifications for Silt Fences, Storm Drain Protection, Dust Control, Seeding, Grading Practices, and Trackout Control Practices.
BMPs: Trackout Control Practices
In alignment with the Clean Water Act, the stated purpose of Trackout Control Practices is to “to identify common methods which may be used to prevent, reduce, and/or mitigate the tracking of sediment.” The Wisconsin DNR identifies three methods to minimize trackout.”
- Prevent trackout with stabilized work surfaces and reduced vehicle contact with soil.
- Reduce trackout with a stone tracking pad, manufactured trackout control devices, or tire washing.
- Mitigate trackout with street cleaning.
WisDOT & DNR Construction Entrance Detail
The Wisconsin DOT relies on the DNR's Environmental Analysis and Sustainability program (EAS) to inform the Stormwater Management procedures for transportation projects. Each transportation project will contact a transportation liaison. The DNR-established BMP manuals and standards are used for WisDOT projects across the state.
The use of stone-tracking pads is the traditional method for minimizing trackout on construction sites. The DNR standards specify the dimensions of the stone tracking pads and the type of stone to be used on the entrances.
The DNR detail indicates that stone tracking pads consist of a 12” layer of rock that is installed over a geotextile fabric. At least 90% of the stone used on the tracking pad should be 2-1/2” or larger. The tracking pad must be at least 50’ long and should be either the full width of the access point or at least 12’ wide if exiting traffic is restricted to a dedicated egress lane. Surface Flows should be diverted away from tracking pads, and runoff from tracking pads should be contained using sedition control practices.
When compaction occurs, scraping, loosening, or top-dressing with additional aggregate is required to maintain the tracking pad's effectiveness. If effectiveness is not restored by these means, the geotextile and stone must be replaced. Adding stone to an entrance is often required bi-monthly due to regular traffic and after each rain event, which can cause rapid compaction.
FODS Reusable Construction Entrance: Manufactured Trackout Control Device Detail
FODS Construction Entrance Mats consist of a single layer of 12’ wide and 7’ long mats, which are linked together and staked to the ground. The tops of the mats are formed into a geometric pattern of pyramids, which deform tires and allow sediment trapped in the tire tread to fall to the base of the mat. Sediment at the base of the mat does not come into contact with subsequent vehicles, allowing FODS to continue to perform even in heavy traffic. The pyramids are staggered in the direction of travel, which ensures all areas of the tires are cleaned.
FODS reusable construction entrance mats are designed to replace traditional stone tracking pads. According to the DNR Standards, FODS should be deployed at “a minimum device length of 32 feet for stand-alone installations. Add length if needed to reduce trackout in adverse conditions.”
Maintenance is required when 2.5” of sediment builds up at the base of the mats. Maintaining mats is accomplished by simply removing sediment using a FODS shovel. The FODS shovel is designed to fit between rows of pyramids, enabling quick sediment removal. Alternative cleaning methods include using a skid steer with a broom attachment, a street sweeper with an adjustable brush head, or a pressure washer with adequate runoff containment.
Wisconsin DNR Approved Use Of FODS Trackout Control Mats
The Wisconsin Department of Natural Resources has approved the use of FODS Trackout Control System for use on projects throughout the state. The Conservation Practice Standard - Trackout Control Practices 1057 lists design criteria for establishing stabilized construction entrances and specifies a minimum length of 32’ of matting and advises installing per manufacturer recommendations.
Contractors can benefit from using the FODS Trackout Control System on their projects. The System is practical, lightweight, and can significantly reduce the costs of minimizing trackout.
Please contact us to learn more about using FODS in Wisconsin.
Additional Resources:
Wisconsin DNR Technical Standards
Technical Standard 1057: Trackout Control Practices