Street Maintenance Chip Seal Program
The Street Operations & Maintenance Division seals the surface of about 100 blocks of its streets each year using the chip seal method. The City will usually chip seal the last two weeks of July and into the first week of August, depending on weather and other factors.
Chip sealing work for 2023 will begin on July 17.
The list of streets to be chip sealed in 2023 is shown on the Street Maintenance Chip Seal Program Flyer, which also includes maps of work locations.
The main reasons for chip sealing Missoula’s streets are:
- to save money by delaying more costly reconstruction work,
- to maintain the existing pavement condition by delaying further aging from sun exposure,
- to provide a moisture barrier, which helps prevent potholes, and
- to improve the texture of the street for skid resistance.
How We Chip Seal
- Clean the street of any debris and patch any holes or cracks.
- Apply hot liquid asphalt (oil) on the street. The temperature of this oil is 140-180 degrees F.
- Apply the 3/8-inch washed aggregate (chips) quickly over the hot asphalt. Rubber-tire rollers then set the rock into the fresh oil. The chips are left on the street for 2 or 3 weeks to ensure they embed into the asphalt as much as possible
- Sweep the street to remove surplus chips.
What Residents Should Do
- Please drive slowly and avoid spinning wheels or making sharp turns on the newly sealed surface. These cause permanent ruts and may damage vehicle paint.
- Ensure trees are pruned to a minimum of 14 feet over the street to the inside edge of the curb line (per Missoula Municipal Code 12.32). Trees not meeting this requirement may be trimmed by the City in order for equipment to move under them and access the entire street.
Did You Know?
Dump trucks are pulled backwards while chipping.
The chipper has a bar on the back and the dump trucks back into this to lock into position. They are then pulled backwards by the chipper with their box in the air dumping out chips.