Chip sealing work gets underway on June 1st in Ada County The Ada County Highway District announced it will begin chip seal treatments on select streets in Boise and Meridian. Author: KTVB Staff Updated: 12:59 PM MDT May 21, 2021 ADA COUNTY, Idaho — Attention drivers! Getting ready to slow down and experience some inconvenience on roads in Ada County this summer. The Ada County Highway District announced it will begin chip seal treatments on June 1st on select streets in Boise and Meridian. ACHD plans to chip seal more than 300 miles of roadway in Ada County this summer. The highway district says Zone 2 South, which is located south of Interstate 84 to Lake Hazel Road, and Five Mile Road west to McDermott Road, will receive chip seal treatments.