THE FOLLOWING IS A CITY OF DANVILLE RELEASE
One of our most challenging yet important functions is maintaining 354 miles of roads. While many are too deteriorated to save, we cannot ignore maintenance and focus solely on replacement. Such an approach would lead to even more failed roadways. Our goal is to provide the right pavement treatment, in the right places, at the right times, so that you get the best “bang for your buck”. Strategic pavement preservation is the cornerstone of our efforts to salvage good roads so that we can reconstruct failing ones.
One strategy people complain about is when we use cape seal instead of asphalt; however, the benefits are stupendous. Last year, we cape sealed over 23 miles of roadway for around $1.7 million with a life expectancy of 8-10 years. If we had used asphalt instead, it would’ve cost approximately $8 million with a life expectancy of 12-15 years. The cape seal method provides a similar result to asphalt at approximately one-third the cost.
The only regular sources of revenue for annual road maintenance are the local motor fuel tax ($1.2 million) and state motor fuel tax ($1.5 million). $2.7 million could provide the following quantities of treatment: 0.5 – 1 mile of road reconstruction, or 3.5 – 5 miles of mill and overlay, or 10 – 20 miles of pavement patching, or 16 – 21 miles of cape sealing, or 43 – 50 miles of sealcoat (chip seal), or 125 – 167 miles of crack sealing. Fortunately, recent sound fiscal practices have enabled road investments well above these levels. Below is a brief summary of treatments used the past two construction seasons.
Crack Sealing (35.6 miles/14.1%): Larger cracks are routed, cleaned, and filled with a flexible sealant that stops penetration. This lowest and most cost-effective preservation method reduces pavement failures by preventing softening subgrade, corrosion, and separation of pavement layers. It costs $15,000 – $20,000/mile and extends roadway life 3-5 years.
Sealcoat/Chip Seal (52.9 miles/13.1%): A thin layer of asphalt binder (oil) is applied followed by a thin application of stone (chips). We apply this treatment to roadways that were originally constructed as sealcoat road (one-third of City streets), or as a preservation treatment on asphalt pavement. It costs $50,000 – $58,000/mile and extends roadway life 5-7 years.
Cape Sealing (50.2 miles/15.2%): Consists of a chip seal treatment followed by a micro surfacing treatment applied to asphalt roads that are in fair to good condition. It seals the pavement, improves skid resistance, protects against oxidation, and restores a uniform appearance. It costs $120,000 – $150,000 per mile and extends roadway life 7-10 years.
Concrete Patching (4.9 miles/2.6%): Involves removal of existing failed portions of pavement and replacement with new concrete. Typically, this is limited to roads where the failures are severe enough that other more temporary patching methods are inadequate. It costs $125,000 – $250,000 per mile and extends roadway life 5-15 years.
Mill & Overlay (6.4 miles/1.8%): The surface of bad asphalt roads is ground off (milled) to remove defects and deteriorated asphalt (usually to a depth of 2-3 inches) and replaced with a new asphalt surface. Occasionally, just an overlay without milling is placed on concrete streets to extend pavement life before reconstruction is required. While this looks like new pavement, it relies on the existing pavement and base for support. It costs $500,000 – $700,000 per mile and extends roadway life 12-20 years.
Reconstruction (8.2 miles/2.4%): Involves a complete rebuild that usually impacts the road, sidewalks, driveways, curbs, and utilities present. Reconstruction methods vary but are very disruptive and costly, so they are reserved to cases in which other options are not viable. It costs $2,500,000 – $5,000,000 per mile and extends roadway life 30-50 years.
Tennis champion Arthur Ashe reminded us that we must “Start where you are. Use what you have. Do what you can,” when facing challenges. We’ve been doing that with our roads for the last five years and have improved over half of them as a result. This would have been impossible without the vision and dedication of our City Engineer Sam Cole and his team, and we’re forever grateful for their efforts. We’re making this an even better place to live, work, invest, and play, one mile at a time and you can see the results.
