What are the processes and procedures for repair work on roadways in the Rural Roads Program?

Hot mix asphalt (HMA) patching is a common technique used to repair tar and chip roadways when existing roadway conditions are in poor, fair, or satisfactory condition. When existing roadways are in poor condition, heavy patching using HMA and sometimes full reconstruction are needed. When a roadway is in fair or satisfactory condition, roadways are patched with HMA in areas experiencing distress. A tar and chip resurfacing is performed on roadways that are in good to excellent condition. Roadways are typically resurfaced on a 4-year to 7-year cycle based upon the roadway’s needs as described above. PMP evaluates tar and chip roadway conditions biennially. In previous years, the patching on these roadways was performed by in-house Highway Operations staff. Most all of this patching is now performed by PMP contractors.  A HMA patch is utilized to repair the damaged roadway area which tar and chip resurfacing cannot effectively repair. HMA asphalt increases the pavement section and can be slightly sloped which provides additional support and proper drainage that prevents future cracking. A tar and chip wearing surface is applied at ¼” to 3/8” thickness uniformly over existing conditions and has very little structural value. A pavement section is a series of road construction layers with the goal of distributing vehicle loads over a larger area so that it will not exceed the bearing capacity of the subgrade. An asphalt pavement section consists of a soil subgrade, stone subbase, base asphalt and one to several layers of surface asphalt. The soil subgrade and stone subbase are susceptible to structural defects from water penetration. The layers of asphalt are used to provide the needed extra support and provide cross-sectional drainage. A tar and chip pavement section consists of a soil subgrade, stone subbase and layers of tar and chip. Once cracking distresses appear in the tar and chip layers, the support system is compromised and can quickly deteriorate. Patching with stone and tar and chip would provide a shorter lived repair that ultimately would worsen and settle between recommended treatments. Full reconstruction would then be required which is far more expensive than patching with HMA and applying the wearing course. This repair method is an industry standard practice for tar and chip roadways as a tar and chip wearing surface is then placed over the HMA patch. 

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1. How do you notify residents of upcoming work?
2. What are the processes for patching on Tar and Chip roadways?
3. How does the County’s paving work tie-into my driveway?
4. Are roads widened during construction of Pavement Management Program contracts?
5. What are the procedures for shoulder backup and turfgrass establishment?
6. How can a homeowner get millings for personal use?
7. What are the surface types and how can they be changed?
8. What are the processes and procedures for repair work on roadways in the Rural Roads Program?
9. Does the Pavement Management Program maintain gravel roads?
10. Is patching a tar and chip roadway considered a maintenance activity permitted in the current Rural Roads Program?