Federal budgetary pressures will probably force the Coast Guard to begin charging for its vessel traffic system - a program similar to air traffic control - that is in place at five U.S. ports and under development at several others.

Although the Coast Guard's official position is still that it will not levy a charge on vessels entering and leaving port, Coast Guard officials and maritime industry sources say that fees are inevitable given federal cutbacks.VTS is a high-tech radar program that promotes safety by tracking vessel movements in a congested harbor. The system operates as an additional layer on top of navigation services provided by pilots, the ship's own equipment and, in the case of the ports of Los Angeles and Long Beach, a vessel-reporting system operated by the local Marine Exchange.

The Coast Guard already operates VTS programs in Valdez, Alaska; New York/ New Jersey; Houston/Galveston; San Francisco/Oakland, and Seattle/Tacoma, and will oversee and staff the Los Angeles/Long Beach system once it is on line.

While the Coast Guard twice asked Congress for funds to establish the traffic system in Los Angeles/Long Beach, it was turned down. Now, Southern California can't wait any longer, since a state law - passed after the disastrous Exxon Valdez oil spill in 1989 and a serious oil spill in Southern California the following year - the state must establish a VTS for the harbor by early 1994.

The Los Angeles VTS will require about $1 million seed money to purchase equipment and will have to pay the Coast Guard $255,000 a year for the six officers it will assign to work in the program.

No matter what the cost of setting up the system, it will entail user fees, Pete Bontadelli, administrator of the state Office of Oil Spill Prevention and Response, told a meeting of the Steamship Association of Southern California last week. The Southern California system would therefore become the first fee-based VTS program in the nation. Fees will likely range from $200 to $380 for each vessel call, depending on the size of the ship.

Larry Keller, the steamship association's president, said that even though the Coast Guard's official policy is not to charge for the systems, the agency is under severe budgetary constraints and may well have to start charging for its services in a few years.

Although not stated explicitly, the Coast Guard itself has hinted that user fees are coming.

Last Wednesday, Rear Adm. R. D. Herr, commander of the 11th Coast Guard District, told the Los Angeles/Long Beach Propeller Club that the federal Oil Pollution Act, which was spawned by the Exxon Valdez spill, significantly increased the Coast Guard's responsibilities for ensuring vessel safety, but Congress is not giving the agency more money.

Although he did not mention the systems specifically, Mr. Herr said that anticipated budget constraints will force the Coast Guard to do more with less, and this will require forming partnerships with state and local agencies and the private sector.

In a scenario in which the Coast Guard will charge as much as $380 for each port call, the ports of Los Angeles and Long Beach could have a considerable competitive advantage over other ports. A California state law mandating immediate implementation will mean the port community can develop the system on its own, without having to comply with expensive Coast Guard procurement procedures.

"The Coast Guard procurement process makes the state procurement process look easy," Mr. Bontadelli said.

A partnership between the state and the Marine Exchange of Los Angeles/Long Beach, which will develop the system, should be able to start up the VTS for about $1 million, Mr. Bontadelli said. By comparison, the Coast Guard estimated its VTS system for Southern California would cost $19 million, and a recent expansion of its San Francisco VTS cost $4.2 million, he said.

Shipping executives in Southern California, therefore, are beginning to say that the system they at first opposed may actually give them a competitive advantage.

Manny Aschemeyer, executive director of the Marine Exchange of Los Angeles/Long Beach, said he sees the Coast Guard's free VTS lasting at most five years, and then port users nationwide will have to pay.

"We are setting a positive precedent. Our fees are lower than what the Coast Guard would impose elsewhere," he said.