Frequently Asked Questions
What improvements are being made to the 8th Street Extension?
ACHD is making improvements to a 1.3 mile section of 8th Street, also known as Sunset Peak, to enhance durability and reduce maintenance needs. The project includes reshaping and regrading the roadway with ¾ inch gravel, reinforcing key ditches to control runoff, and applying an otta seal surface treatment.
What is an otta seal?
An otta seal is a type of oil-based road treatment that seals the surface to reduce dust, improve durability, and reduce maintenance burden. This treatment will preserve the current recreational use and look of the area while addressing the current maintenance challenges, which benefits adjacent residents and road users.
Why is this work necessary?
The 8th Street Extension requires frequent maintenance due to ongoing issues such as washboarding, rutting, drainage erosion, and excessive dust. On average, ACHD currently grades the road 17 to 24 times per year, applies dust control five times annually, and repairs washouts six times per year. These efforts require significant resources, and the proposed treatment will help preserve the road’s appearance and functionality while reducing the need for constant upkeep.
When will the work take place?
Construction is scheduled to begin in April, depending on weather conditions, and is expected to be completed by the end of May. The road will remain open with lane restrictions during this maintenance project and ACHD asks that users obey construction signs and flaggers at all times. In addition to this project, ACHD will be installing a culvert on the paved section of 8th Street as part of a separate drainage project. This work will require a full road closure but will be scheduled to coincide with the roadway improvements to minimize disruptions.
Why otta seal 8th Street?
Otta seal enhances the road’s durability and overall quality while minimizing disruptions for users. This application significantly reduces ongoing maintenance, cutting down the need to apply magnesium chloride for dust control (typically required over 20 times per year) and reducing or eliminating the need to grade washboards (previously done 6-10 times per year). By using otta seal, we’re creating a longer-lasting, smoother, and more sustainable road surface.
How is otta seal different from other treatments like chip seal?
Otta seal is like chipseal but uses larger pieces of aggregate and liquid asphalt to make a less permeable road surface. Unlike traditional chip seal, this application will not include a fog seal or final oil layer, which typically darkens the surface. This approach helps maintain the natural appearance of a gravel or dirt road while still providing durability and reduced maintenance needs.
Have we done this anywhere else in the county?
ACHD has used this treatment on other roadways within the county, Blacks Creek Road north of the freeway is an example. However, the application on 8th Street will be slightly different—unlike previous projects, it will not include a final oil layer or fog seal. This adjustment is intended to maintain the appearance of a gravel or dirt road.
How will construction affect access?
During the otta seal application process, residents will still be able to use the road. Crews will work on one lane at a time to ensure that travel can continue. While minor delays, flagging, and construction noise should be expected, efforts will be made to minimize inconvenience for residents and road users.
*Please note that a separate drainage pipe project will occur on a lower section of 8th Street that will require a full closure of the roadway. While this is an unrelated project, our team is coordinating the work to run in tandem in an effort to reduce impacts on commuters and residents.