Road Maintenance

Public works staff focus on the daily maintenance and repair of existing roads and rights-of-way.

A variety of programs are used to help keep our roads in the best possible condition and extend their service life. Below are definitions of commonly used pavement maintenance techniques.

Patch and Repair

When a small isolated section of roadway fails, we call it a "pothole." Typically water has seeped under the pavement surface, creating pockets of water that fracture the surface when traffic compresses the water underneath. These potholes are temporarily repaired with a cold asphalt mix. If a section of roadway has numerous failures, it's because the sub-base under the road surface is compromised. Permanent repair may be delayed until a better solution can be funded and implemented.

Crack Seal

Asphalt pavement is designed to be flexible for adaption to the wide temperature swings in Arizona. The flexing causes cracks to develop in even relatively new pavement, and will continue to crack throughout the usable life of the roadway surface. To limit deterioration, cracks are filled with a rubberized sealant called "crack seal" that keeps out water and fills voids in the surface.

Sealcoats

Three types of sealcoats may be applied that will extend the life of the pavement. An acrylic seal is a thin layer of asphalt emulsion that prevents oxidation and adds asphalt material to the surface course. For seal protection and added wear surface, a slurry seal mixture made of asphalt emulsion, water and sand is applied. Chip seal is a thin asphalt emulsion followed by small grade aggregate providing additional surface wear and sealing to road surface.

Mill and Overlay

If large areas of a roadway are showing signs of structural failure, potholes or “alligator” cracking, the section can be milled down to the good pavement base. This is followed by a new hot-mix asphalt overlay, extending the life cycle of the original pavement.

Reconstruction

When a roadway has reached the end of its life cycle and can no longer be rebuilt, a new road must be constructed. All existing pavement will be removed and recycled for use as a new sub-base. The old sub-base will be regraded and compacted and a new hot-mix asphalt surface applied.

Service Cuts

The most common work seen on the road does not relate to pavement maintenance. These are areas where utility crews cut into the road surface, digging down below the surface to add or repair sewer, gas or water lines. During the course of construction, contractors will cover these areas overnight with metal plates or an asphalt patch mix. When completed, the area is re-compacted, a new sub-base installed and a hot-mix asphalt applied.

Street Sweeping

Public Works staff contract street sweeping services. Clean streets provide safe driving conditions, improve air and storm water runoff quality.

Right-of-Way Maintenance

Streets crews maintain right-of-way (ROW) areas, including weed abatement.