By Michael E. Shaw

Scarborough Public Works director

Asphalt pavement or “flexible pavement” is the road surface of choice in the northeast, unlike cement roads you see in warmer climates. Asphalt pavement has the elasticity to move up and down with the ground as it freezes and thaws. This is not to say the road won’t crack over time, but it will take more time to do so.

Another reason we use asphalt pavement is salt. While road salt used to treat ice in winter has no effect on asphalt it will cause cement to spall and break apart. Recent advances in cement design have minimized this problem but it still has a way to go.

Asphalt cost $30 per ton five years ago when I became public works director. This year Scarborough received a per-ton price of $61.48 through the Council of Governments bid process. This doubling of cost is directly related to events in the petroleum industry. 

Pavement is nothing more than asphalt cement used as a glue to hold sand and rock together. When you add the cost of fuel to truck and to mine the materials you see why cost has increased.

You may wonder how we determine the list of roads that get paved annually. Public Works has a pavement management process that grades roads from 0 to 100. The grading process is based on a number of factors. The condition of the road surface is only part of the grade. Drainage and level of traffic play a role as well.  

For instance, if you have two roads with similar defects, such as cracking, and one road serves 10 homes and the other is a local connector, then the local connector will be repaired first. The goal is to keep roads serving the most users in good shape while still repairing side roads as funds allow. It is a difficult balancing act.

There are a number of maintenance options available. These range from crack sealing to heavy pavement overlays. If we can seal cracks, we can extend the life of the road and not get into more expensive repairs such as pavement overlay.

Over the last few years we have received approximately $550,000 annually to cover expenses for pavement and pavement repair. Although this is a generous amount of money, with the 171 miles of road in Scarborough there is a definite need for the funds. In fact, if we were to pave one mile of road with 1 inch of hot top it would require 650 tons of pavement. At a cost of $61.48 per ton it will cost a total of $39,962 to pave that mile. If we take that further, of the 171 miles of town roads, assuming that pavement prices remain level, we can pave 14 miles each year. It would take 12 years to pave all the roads in Scarborough.

The Scarborough Fire, Police and Public Works Departments produce a weekly feature for the Leader educating the public about various duties of the departments and public safety issues.