For example, tiny, almost invisible cracks can cause moisture to accumulate beneath the surface. When frozen, the water expands into ice, and may cause highways to crack or erode. In other cases, years of hot, arid weather may cause a highway nearing the end of its design life to dry out and start to unravel. In this instance, resurfacing may be necessary to prevent additional damage. Like the tires on your car, highways must also be replaced before they're too worn out to provide the proper safety and service they were designed to give.
Designers take into account several factors when planning a highway.
They look at the purpose, location, traffic density and volume, load limits and many other factors. They attempt to balance function with cost to come up with a roadway that will give many years of useful service at a reasonable cost. Most of the time we do. We have a toll-free road reporting hotline that is updated frequently. On major projects we notify the media before work starts, and place signs at key points along the route.