Analyze the condition of the roadways every year, on-site, with a computerized pavement management system.
Combine the data gathered from the annual analysis with other information about each roadway, including:
- road classification
- road surface type
- the average cost to restore the road to its proper functioning condition
Create a prioritized list of roadway repair and maintenance projects based on the most cost-effective timing of repairs.
Develop preliminary cost estimates for each likely project based on historic costs per lane mile.
Compare the preliminary cost estimates with estimated budget amounts and group the projects into a five-year plan.
Compare and, as needed, revise the five-year plan with project lists from other agencies and organizations that may need to work on the roadway, including the County Development Agency, County Water Environment Services and other utility providers.
This saves money, time and inconvenience to the public by reducing how often work is needed on a particular roadway.
Group the final list of road projects into contract packages, taking into account road work not completed from the previous year and road work that will be needed in the following year.
Combine the contract packages into projects within specific geographic areas and give other local agencies the chance to add their own projects to the packages.
In the past, the cities of Milwaukie, Oregon City, Canby, West Linn, Gladstone and Estacada have had roads paved through this process. This grouping of projects supports higher quality work at a lower cost:
- It allows contractors to provide work at a lower cost for County and city citizens by bidding on larger amounts of asphalt and amortizing some of the mobilization costs.
- It allows the County to efficiently schedule the inspection teams needed to help contractors deliver a quality product.
A multi-phase construction process is used to do the actual road restoration.
- First, during the winter and spring County crews repair the roadway's drainage and road base. This may include reconstruction of drainage and ditch systems, repair of failed road base sections and preparation for any other work such as reconfiguring an intersection, adding a bike lane or improving a shoulder.
- During the summer, contractors place asphalt on the roadway. After this paving is complete, County crews re-stripe the roadway.
- The last step takes place during the fall, when County workers reconstruct the shoulders on the roadway. This work is scheduled in the fall for two reasons.
- County staff can mobilize and complete the shoulder work of the entire paving project in the most cost-effective manner. In the past, we have attempted to include this phase within our contracts, but private enterprise cannot complete this task as economically as Clackamas County.
- The rain that typically comes in the fall provides enough moisture to keep the roadway and shoulder rinsed off throughout the entire process, eliminating the dust problems that occur when the operation takes place during the dry summer months.
The result is:
- a safe roadway
- with rock or paved shoulders
- that drains properly and
- has a life expectancy of 15-20 years with regularly scheduled maintenance*.
*Over time, oil in asphalt oxidizes and becomes brittle. County crews typically apply a chip seal to the roadway 7-10 years after the paving is completed to seal any small cracks that may be forming and restore a flexible surface to the roadway. This may be done two or three times during the life of the pavement.