Down With the Poles? Up With The Costs

Another concern was the potential health effect of exposure to electromagnetic fields, particularly in the historic district, where 18th century rowhouses are so close to the street-side utility poles. (Such fields are invisible lines of force that surround any electrical device. Studies vary on the amount and type of health risks they present.)

Aesthetics were the final concern. Those poles and wires just don't fit with Old Town's character. However, maintaining that character presents some additional problems and costs. For example, the historic granite curbing must be preserved when utilities are moved, because to replace it would be even more expensive.

The cost of the Alexandria project is shared between the city and Virginia Power. Through its capital improvement budget, the city has embarked on a pay-as-you-go system, setting aside funds annually. Each phase of the six-phase project covers a four-block area and costs $2 million per block, said Baier. Emily Baker, city engineer, noted that it takes several years to design a phase, so money is accumulated before the next phase begins.

Burying utility lines does not entirely eliminate aesthetic concerns. Because of a high water table, above-ground transformers -- either pad- or pole-mounted -- generally accompany underground utilities in this area. The pole-mounted ones are similar to the silver cylindrical transformers now used on overhead lines. The pad-mounted transformers are those 3-foot by 4-foot or larger metal boxes on the ground that are almost as unsightly as the overhead equipment.

The boxes are often targets for graffiti; because they need to be readily accessible, plantings that could be used to camouflage them must be limited.

It's kind of like a tot lot, said Baier. "Everyone wants one, but not next to their house."

Reliability and Repairs

Underground utilities are not foolproof. Outages still happen. Repairs will be needed.

Even though underground utilities are not directly subject to wind and ice damage, or to being hit by vehicles, they are not independent of overhead lines. If an outage occurs in an overhead feeder line, it can affect areas where lines are buried. And those pad and pole transformers are vulnerable.

Underground cables are subject to water damage, corrosion from chemicals used to de-ice streets in the winter, and accidental cuts during digging. Problems can be time-consuming and difficult to locate. Often, large areas must be excavated to reach the source of the problem, making repairs costly -- not to mention destructive to landscaping.

Many utilities in older neighborhoods were not designed to handle the increased load that today's use demands. Expanding service is much easier with overhead lines. Verizon's Creager noted that an urban community may already have underground cable, but the conduits may be too crowded for added service. New services have to snake in and around existing ones.

"The biggest cost factor is not knowing what else is hiding down there," said Steve Caneen, president of Florida-based Huxted Tunneling. That uncertainty is what drives up the costs.