Overlay and Chip Seal Programs

Each summer, Snohomish County Public Works refurbishes a series of designated county roads through its Overlay and Chip Seal Programs. To provide advance notification to the impacted communities, the County places ads in newspapers and crews post signs prior to beginning work in an area. Paving, however, is weather dependent work, and the road list (link provided) and planned work schedule may require adjustment.

2011 Snohomish County Resurfacing Program (pdf)

Projects Shown on Maps

 NW County (pdf)

 NE County (pdf)

 SW County (pdf)

 SE County (pdf)

 Entire County with Council Districts (pdf - 1 MB)

Overlay Program

• Thin overlays: The County's Road Maintenance crews put 1 to 1.5 inches of asphalt on residential streets marred by potholes and minor deterioration.
  
• Thick overlays: The County's contractor applies 2-3 inches of asphalt on moderately to severely deteriorated arterials and residential streets in need of "structural" overlays.
  

Chip Seal Program

2011 Newsletter & List of Chip Seal Roads

Chip sealing is a cost-effective option for preserving and extending the usable life of a road by 7 to 10 years. The process involves the following steps:

Preliminary Road Preparation: 

• If needed, County Road Maintenance crews will repair potholes, seal cracks, and/or pre-level the road surface by applying a layer of hot asphalt.
  
• Within a month (typically) following the pre-level work, crews place crushed rock along the shoulders and stripe or place temporary markers where necessary.
  
• Brush cutting, road sweeping, and other preparation work takes place prior to the chip seal placement.

Chip Seal:

• A layer of asphalt oil is applied to the road when weather is sufficiently warm and dry.
  
• This is immediately followed by a layer of crushed rock, creating a "chip seal."

• The chips are pressed into place by a roller and the road is immediately usable however, the compaction and adherence of chips to the asphalt binder improves with time and routine but SLOW traffic.
  
• Crews return within a week to sweep up loose gravel and replace pavement markings.

Please Be Aware:

• A regulatory speed limit of 20 mph will be in effect during the week following the chip seal placement.
  
• Adherence to this temporary speed limit will minimize the likelihood of loose, flying chips causing damage to a vehicle’s body or windshield. Faster speeds and turning movements may also compromise the resulting quality and life expectancy of the new roadway surface.

• Snohomish County Sheriff’s Deputies will be patrolling the chip seal projects and will enforce the 20 mph regulatory speed limit. Remember, fines double in work zones. Slow down, and “Give ‘em a break.
  

Overlay and Chip Seal History (1989 – 2009)

List Sorted by Road Name (pdf)

List Sorted by Project Year and Then by Road Name (pdf)

Questions?

• For information about the program, contact Joyce Barnes at
  (425) 388-3488, ext. 4530.
  
  
• For information about the Thick Overlays schedule, contact Charlie Mathison, (425) 388-6673. If you have a question or comment about the construction phase of the work, contact Hamid Aslani, (425) 388-3488, ext. 4294. 
  
  
• For information about the Chip Seal schedule, contact Duane Myers, Snohomish County Public Works Road Maintenance at (425) 388-7500, or 1 (800) 562-4367 ext. 7500.

(TTY: 425-388-3700).