Plans to implement a $520 million expansion of the San Diego Convention Center may be held up by a hotel tax that's been proposed to pay the lion's share of it. Plans call for a new tax of up to 3 percent on room rates, which would generate as much as $35 million a year, according to the San Diego Union-Tribune. Meanwhile, the Port of San Diego is being asked to contribute just $3 million annually over 20 years and the city $3.5 million annually over 30 years. The city's hoteliers, who will begin voting on the tax later this month, argue that they will not approve the levy unless they get greater representation on the San Diego Convention & Visitors Bureau's board, currently composed of 30 members, half of whom have ties to local hotels. But some council members, whose votes would be needed for the amendment to pass, have made it clear they will not support a change in the board’s composition. At the same time, the San Diego Convention Corp. is weighing the possibility of turning over its responsibilities for booking conventions and trade shows at the center to the CVB, which hoteliers say also is essential if they are to vote for the tax. This week, a flurry of meetings involving the SDCC, the CVB and the City Council will attempt to clarify the situation and pave the way for implementation of the tax.