Mar. 26--Demand for space at the $800 million convention center being built in South Boston will be significantly less than projected five years ago when lawmakers authorized the publicly financed facility, according to a new study to be released this week. 

The report from PricewaterhouseCoopers, a draft of which was obtained by the Globe, states that after a five- to seven-year ramp-up period, "the new Boston Convention and Exhibition Center should achieve occupancy in the range of 35 to 40 percent and an annual attendance of 360,000 to 410,000." 

But critics say that five years ago, when proponents were urging lawmakers to fund the project, the backers estimated annual attendance would reach 470,600 within five years of its opening. 

If PricewaterhouseCoopers is correct, attendance could be as much as 25 percent lower than originally forecast. Under the worst-case scenario, that would translate into 9 percent fewer hotel room nights being booked. 

The study offers no estimate of how many events the new facility will host each year. 

"It's like comparing Arabic and Chinese," said Charlie Chieppo, a spokesman for the Pioneer Institute, a conservative Boston think tank, who is a leading critic of the project. 

"For more than five years," he said, "all of the studies have measured the new center's projected impact in terms of number of events and hotel room nights generated. The idea of referring to 'percentage of occupancy' has never been used before, so it completely obscures the steep decline in demand." 

"People make mistakes, but they should admit it straight out," Chieppo said. "It's clear the center is not going to perform as they predicted." 

The draft report includes a menu of controversial options to beef up bookings at the 700,000-square-foot facility. The proposals include allowing gate shows -- events catering primarily to local audiences, such as boat and home shows -- and selling the Hynes Convention Center. That would allow officials to transfer conventions currently booked at the Back Bay facility to the new building. 

The study estimates that eliminating the current ban on gate shows at the new Boston Convention and Exhibition Center could increase bookings by as much as 20 percent a year. And closing the Hynes, which has an annual state subsidy of roughly $17 million, would eliminate the need for public funds to operate two buildings. 

Implementing those suggestions would require amending the 1997 legislation that authorized construction of the new facility. 

South Boston political leaders adamantly oppose lifting the ban on gate shows. Conventions attract tourists who fly into town and stay for days in hotels, but gate shows draw regional attendees who drive in for the day, they say -- creating the potential for traffic problems in South Boston. 

In addition, the owners of private halls, such as the World Trade Center in South Boston and Bayside Expo Center in Dorchester, are opposed to the idea of creating a publicly subsidized competitor. 

Leaders of the hospitality industry, which paid for the PricewaterhouseCoopers study, also are cool to gate shows. 

"I've never been a big fan of doing gate shows, because they don't generate the number of hotel room nights that the new building was meant to produce," said Patrick Moscaritolo, president of the Greater Boston Convention and Visitors Bureau. 

"I understand that [gate shows] will generate bookings for the new facility and give the Convention Center Authority some revenue, but not anywhere near the economic spinoff effect you get from full-fledged conventions." 

The convention center is scheduled to open in 2004. So far, 18 conventions have confirmed bookings for the facility's first decade. 

The study says Boston remains "an attractive destination" for meeting planners, but emphasizes the huge hurdles faced by those charged with marketing the new facility -- including the severe shortage of reasonably priced hotel rooms adjacent to the building, and the lack of public transportation in the area. 

The report was paid for by the visitors bureau and the Massachusetts Lodging Association. It was intended to evaluate changes in the convention industry marketplace due to the softening economy and increased competition spawned by the recent boom in the construction of convention centers across the country. 

Massachusetts Convention Center Authority officials expressed disappointment in the report, saying it lacks detail on how much demand there is for the new facility. 

"The report is not only confusing, but it's unclear on the central question: What is the current demand?" said James Rooney, director of construction for the facility. 

The report "seems to be a litany of excuses for the lack of bookings to date -- transportation systems, shortage of nearby hotels -- all of the things we knew would be hurdles five years ago. But the building is going up, and what we need is an energetic and aggressive marketing campaign to bring the clients we need to fill it. That isn't here." 

The study, commissioned in June, was scheduled to be released last fall, but was revised after the Sept. 11 terrorist attacks. 

Yesterday afternoon, Moscaritolo said he could not comment on details included in the report because he had not seen the final version yet. The report is expected to be released tomorrow, and several key political leaders, including Mayor Thomas M. Menino of Boston, were slated to be briefed on the report last night. 

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(c) 2002, The Boston Globe. Distributed by Knight Ridder/Tribune Business News.