Littlerock Community Pavement Preservation Project

The project is located in the Los Angeles County unincorporated community of Littlerock near the City of Palmdale.The majority of 41 lane miles of primary residential roadways (2.8 million square feet) had intermittent alligator and widespread map and thermal cracking.Since the majority of the streets in the area were in borderline fair to good condition, our goal was to prolong the life of the pavement now with a preservation treatment in order to avoid having the road deteriorate to a point where a resurfacing treatment would be required, and therefore, increasing the treatment cost by 2 to 4 times.We selected a pavement preservation strategy that included micro-milling all the road surfaces, applying a chip seal on the micro-milled surface to the highly distressed roads and then applying either a slurry seal (local roads) or microsurfacing (secondary roads) treatment to all the road surfaces.The micro-milling was utilized to help improve the ride quality of the road prior to applying the pavement preservation treatments.This process was very successful in smoothing out irregularities of the road’s surface as well as removing any excess asphalt material already on the gutters.The chip seal was applied to the micro-milled surface for streets that had more distresses.All roads were then sealed with either a slurry seal (local roads) or microsurfacing (secondary roads).To improve the sustainability of the project we utilized Reclaimed Asphalt Pavement (RAP) rather than virgin aggregate in all treatments.For this project, the County implemented new approaches.First, all concrete work addressing ADA issues and curb and gutter in need of repair were handled by our in-house Road Maintenance forces prior to the pavement preservation treatments being applied.Second, we utilized the Job Order Contract (JOC) process rather than a low bid approach in selecting a contractor which allowed us to streamline the design and contracting tasks.As a result, we were able to prepare plans, secure a contractor and complete the construction within 4 months.Third, a new emulsion was utilized to address the extreme fluctuations in temperature for the County’s high desert roadways.The variations between the extreme heat in the summers and the very cold winters create distresses in the pavement.The emulsion used on this project optimally combines rejuvenating agents and other additives that allows the chip seal to resist softening at high temperatures while remaining flexible at low temperatures.This capability will help prevent reflective cracking and extend the life of the surface treatment.By performing the pavement preservation treatments before the resurfacing treatment would be required, the County was able to reduce the energy consumption and greenhouse gas (GHG) emissions by 79% and 88% respectively, reduced landfill deposition by 12,300 tons, and saved tons of virgin material from being removed from the earth.