POT HOLE PATCHING
Patching potholes and other surface deterioration is a necessary first step. Many methods of patching are available, but Richfield staff uses two patching techniques. Throw and roll starts with staff cleaning the pothole, chipping away unstable blacktop, drying the hole, covering the hole with a "tack" coat to help glue the patch down, filling the hole with hot mixed blacktop and finally rolling the patch into a smooth permanent part of the street. Mill and Patch is a technique that employs a 14" wide mill. Staff mills away the area of the patch then restores the hole in the same way as throw and roll patching.
ROUTE AND SEAL
This method is used for sealing cracks, which in turn keeps moisture out of the sub-grade and prevents further deterioration. The top one inch of the crack is routed out to a width of ¾" by one inch. The channel is the cleaned and heated and filled with a sealant.
SEALCOAT
Sealcoating consists of cleaning the street, applying a coat of liquid asphalt, covering the asphalt with gravel and then sweeping up the excess gravel. If only one maintenance strategy were to be employed it would undoubtedly be sealcoat. Sealcoating a street is the one single best method available for maintaining blacktopped streets.
MILL AND OVERLAY OR OVERLAY
Overlaying a street, with or without milling away the existing surface, is the most expensive maintenance technique available to us. Only a complete reconstruction of the street would cost more that a mill and overlay. The major benefit of this method is that the public gets a new surface with no cracks, potholes or other distress.
If you have any questions, please contact the Engineering Division at (612) 861-9191.
