Maintenance consists of either overlaying or sealcoating. Overlaying is a maintenance activity that includes the patching of the existing street, milling the pavement adjacent to the curb, followed by the placement of a bituminous wearing course over the entire surface. Seal coating is a maintenance activity that places a thin layer of oil and rock on the street to enhance the surface and prolong the useful life of the street. These activities have been routinely performed by the City as part of its pavement management program. These projects are funded each year through the property tax levy as part of the City’s annual budget. This method is useful for smaller projects where the cost of the improvement has a negligible effect on property tax rates and where improvements have a shorter-term benefit.
The selection of streets for these maintenance activities is determined by the City’s Pavement Management Ratings called the Overall Condition Index (OCI). All streets within the City are routinely rated. Streets rated 70 to 100 are in the adequate category. These streets are considered for sealcoating. Streets rated 40 to 70 are in the marginal category. These streets are considered for overlays as well as sealcoats based on their ratings and available funding.
Streets rated in the 0 to 40 range typically need substantial subgrade corrections and require reconstruction. In this case, an overlay or "lift" on a street in this category would quickly return to its present problem condition. Because of the substantial cost involved these projects are typically funded through the issuance of bonds that spread the payments out over a longer period of time. The bonds are repaid through a combination of special assessments to benefited property and property tax levy.