Dec. 13--SAN DIEGO -- Constructing a new commercial airport near Campo or in Imperial County and linking it to central San Diego County would require more than $10 billion in high-speed rail, utility and roadway construction, according to a report reviewed Monday.

The report, presented to a planning committee of the San Diego County Regional Airport Authority, showed an Imperial County site would require $13.2 billion in rail, utility and roadway enhancements while one in Campo would need an investment of $10.2 billion.

Most of the costs would be in construction of a magnetic levitation train, a potential link now being studied by a consultant at the request of U.S. Rep. Bob Filner, D-San Diego. Filner helped secure funding in the most recent transportation bill passed by Congress to study construction of a train powered through magnetic levitation technology.

Building a bullet train to Imperial County would cost an estimated $10.6 billion, while building one to Campo is estimated to cost about $8.1 billion.

Construction of a new airport itself is projected to cost somewhere between $5 billion and $10 billion. The new airport in Denver, the nation's newest airport that is comparable in size to what the authority wants to build, cost a little more than $5 billion when it was completed a few years ago.

Authority board member Xema Jacobson said the financial projections represent the first step in determining the feasibility of airport sites in Campo or Imperial. A high-speed train also could serve as a cargo carrier from the Unified Port of San Diego to Imperial County, which could result in lessening the costs of construction for the airport authority.

Campo, Imperial and an expansion of downtown San Diego's existing Lindbergh Field are the only civilian sites that remain on the authority's original list of 32 potential new airport locations.