Today, while driving around town, I had a philosophical discussion about how you would classify and prioritize the paving projects with a limited budget. There is always a tension between roads that have little traffic that are obviously failing, and those that have a lot of traffic and need regular maintenance to keep them in good condition.
Many traffic authorities have adopted a method based on the US Army Corp of Engineers Airfield Pavement Condition Index (pdf). Which identifies various modes of pavement failure or damage, looks at the severity and density of the problem, then subtracts that from a perfect score of 100. An outline of the methodology is found at wikipedia.
In a city that has some pretty bad pavements and no long term plan for wholesale replacement and repair of the structure, a method like this provides an opportunity to quantify the problem, and even present it graphically in a GIS system.
Sounds like a project. Check out the link to the Pavement Condition Index pdf for more information on the types of damage or distress to pavement. You can buy the ASTM standard based on this method here.