Dust Control Program
The gravel or limestone placed on unpaved county roads contains a gradation of stone sizes, as well as a quantity of clay that acts as a binder to stabilize the crushed stone. Traffic on unpaved roads during dry weather disturbs the clay and airborne dust is generated. Not only is the dust a nuisance to adjacent property owners and can obscure the vision of motorists, it also escalates the deterioration of the road surface since the stone material lacks an adequate binder.
In order to reduce the amount of dust and preserve the road surface, the Washtenaw County Road Commission periodically sprays the road surface mineral with brine or liquid calcium chloride. The Road Commission operates its own natural brine well in Lyndon Township, which is augmented by brine purchased from a private vendor. Calcium chloride is a by-product of brine and is also purchased from a private vendor. The brine or calcium chloride absorbs and holds moisture, thus keeping the road surface damp and dust-free for prolonged periods of time. The calcium chloride has a higher salt content and thus, is a more effective dust control material, however, it is also significantly more expensive.
The Road Commission applies brine to its unpaved Primary Roads at least three (3) times per year. Townships pay the cost of the dust control material used on Local Roads, and the type of material and frequency of application varies.
As part of its dust control program, the Road Commission first thoroughly grades the road, and then sprays on approximately 2,000 gallons of brine or chloride per mile. Since subsequent road gradings will mix the dust control material below the surface of the road, during summer months the Road Commission attempts to restrict gradings on unpaved roads unless they are followed by new dust control applications.
Private Order Dust Control
At the request of a resident, the Washtenaw County Road Commission (WCRC) will apply private order dust control on unpaved public county roads for a nominal fee. If more than one resident on the same road segment is interested in private order dust control, residents may collectively place an order.
How to order private dust control / Fee Schedule:
The completed order form, location map, and payment (check) should be mailed to or dropped off at the WCRC offices, 555 North Zeeb Road, Ann Arbor, 48103.