Pavement Preservation

Pavement Preservation

Staff Contact:
Tobin Bennett-Gold
(425) 398-8900

Final 2019 Slurry Seal Update: Striping contractor punch list has been completed and the work has been accepted by the City. Some pavement markings such as stop bars and symbols are typically applied with thermoplastic, a more durable material. Thermoplastic application is sensitive to pavement temperature and this work is being deferred until warmer, spring weather. In the meantime, all locations that will receive thermoplastic markings have had the symbols marked in paint on the pavement, which will be sufficient until more durable markings can be applied.

Post-Slurry Sealing Update 11/22/2019: Striping of slurry sealed roads is now complete. The contractor has a punch list of items still needing to be completed and will work on those as weather permits.

Post-Slurry Sealing Update 10/25/2019: Striping of slurry sealed roads is scheduled to take place on Saturday and Sunday, 10/26 and 10/27.

Post-Slurry Sealing Update 10/11/2019: Striping layout is now complete and we're working with the contractor to schedule completion of the rest of the work. We will reinstall all pavement markings as soon as possible beginning with high volume streets.


Post-Slurry Sealing Update 9/17/19: Striping of roads has been delayed. We're working with the contractor to get striping scheduled. Updates will be posted when we have a confirmed schedule (as always, weather permitting).


Post-Slurry Sealing Update 9/6/19

  • Work in areas of concern (see 9/4/19 update) has been completed.
  • Striping is scheduled to start Thursday, September 12, 2019 (weather permitting).


Post-Slurry Sealing Update 9/4/19

Thank you for your patience and flexibility while we completed this work! The condition of the slurry sealed roads is consistent with what we expected, and we anticipate that this work will extend the life of these roads for 7 to 10 years.

What’s next?

  • Staff has walked all of the slurry sealed streets and has identified areas of concern.
  •  The contractor is scheduled to return the first week in September (tentatively Thursday, 9/5/19) to touch up or repair areas identified by staff.
  • Bits of aggregate on the surface are a normal part of the slurry seal process.
  • Street sweeping  is scheduled for one week, 3 weeks, and 3 months post-treatment (in addition to our normally scheduled sweeping) to remove the surface aggregate.
  • Gradual smoothing of the roads will occur with normal use of the road.
    • Heavily traveled roads will smooth out faster
    • Low traffic areas will likely take more time to smooth out
  • Striping is scheduled to start Wednesday, September 11, 2019 (weather permitting).


Slurry Seal Map - Updated 8/23/19 2pm 


Rescheduled Roads - August 21, 2019 


List of what roads have been rescheduled (yellow roads)


What Roads Will Be Slurry Sealed and When?

  • Work now rescheduled to begin (weather permitting) August 22, 2019
  • Crews complete approximately 1 mile of road per day (see schedule for specifics)
  • Last day of work (weather permitting) is August 27, 2019


What is Slurry Sealing and Why Do It?

  • Water / Oil / Aggregate mixture in liquid slurry form
  • Spread as a thin coating over existing road surface
  • Preserves and protects underlying pavement structure
  • Extends road life without costly asphalt replacement/overlay

How Are Roads Selected?

  • Aging roads that don’t have a lot of cracking
  • Roads recently crack sealed

Why Were Some Roads Not Selected?

  • Roads in need of major asphalt repair are not good candidates for preventive maintenance
  • Roads with very high traffic volumes are not good candidates for slurry seal
  • Many roads which are good candidates for slurry seal may have been deferred to another year

How Does the Work Get Done?

  • Water/Oil/Aggregate is mixed in the applicator truck on-site
  • Slurry mixture is spread from the rear of the truck
  • Workers follow behind with squeegees to spread the mixture evenly
  • Slurry-sealed roads must “cure” for at least 4 hours
  • Streets are swept for loose aggregate immediately, and after one week, three weeks, and three months.

How Will This Impact Me?

  • Crews spread slurry seal mixture from 7am to 1pm to allow time for curing by 5pm
  • Residents will not be able to use the road (to drive, park, walk, etc.) from 7am until 5pm on the day of slurry sealing
  • “No Parking” signs will be out 24-48 hours in advance of road closure; vehicles parked in work areas on the day of slurry sealing will be towed
  • Roads may appear and feel a little bumpy and rough for several months
  • Roads return to normal roughness after several months
  • Pedestrians, cars, bikes, scooters, strollers, etc. may travel the road after 5pm, although it may not feel smooth for several months
  • You may feel loose bits of aggregate (swept immediately, after one week, three weeks, and three months)
  • Expect normal construction noise and odors


Last updated: Tue, 12/10/2019 - 11:42am