In light of the deteriorated condition of some repaved local roads, whose asphalt surfaces have been degrading much sooner than would normally be expected, the town public works director is expressing caution about spending large sums for extensive road repaving projects while road durability remains in question.

Director Fred Hurley said November 12 that both locally and throughout the state, the durability of repaved asphalt roads has become an issue during the past several years, as those roads have physically deteriorated sooner than expected.

Mr Hurley suggested a range of reasons why repaved roads do not last as long as they formerly did. The problem has affected municipal roads across the state, as well as state roads, he said.

The problem of premature road-surface wear was first noticed about seven or eight years ago and has become more apparent across time, especially during the last several years, he said.

The problem is widespread because the suppliers of asphalt, or “bituminous concrete,” must conform to a formula for its preparation issued by the state, he said.

Among the factors that may be causing the problem, Mr Hurley said the components for asphalt now include a latex-based binder instead of an oil-based binder. That asphalt formula change was made to reduce the amount of “volatile organic compounds” which are released into the atmosphere during paving, thus serving as an air pollution control measure, he said.

Also, the percentage of recycled asphalt, also known as millings, that is included in new asphalt has increased. With a higher percentage of recycled asphalt in use, the adhesives that are used to bind asphalt may not be as effective as in past pavement formulations, he said.

Also, the composition of deicing mixtures that are used for snow and ice control in the wintertime has changed, he said. Such changes may result in briny water coating roadways longer than in the past, resulting in possible asphalt degradation, he said.

Also, some people have questioned whether the quality control for asphalt manufacturing is strict enough to ensure that good quality asphalt is consistently produced, he said.

Mr Hurley noted that several of the asphalt-related changes occurred during a relatively brief period, leaving it unclear which factors are causing lower quality asphalt.

When the town repaves a road, it wants its surface to last at least 15 years, and when it repaves a lesser-used road, it wants such pavement to last 20 years, Mr Hurley said.

However, the road degradation problem has resulted in some road surfaces lasting only five to seven years, or even less, he said.

The state Department of Transportation (DOT) is having technical testing done by the University of Connecticut to learn what is causing asphalt pavement to degrade prematurely, Mr Hurley said. Technical information on what is causing the problem may be available next year, he said.

It would not now be prudent for the town to commit itself to spending large sums for road repaving when considering the road durability issues, Mr Hurley said.

The town has about 275 miles of town roads, of which about 260 miles are paved.