The Hilton Hawaiian Village today announced a 10-year master plan that includes adding two new towers that would almost double the number of timeshare units at the 22-acre resort in Waikiki.

The project, which does not yet have a price tag, also will additional pools and retail space at Hilton's flagship Hawaii property.

The towers will add about 550 timeshare rooms to the existing inventory of 650 timeshare units, said Jerry Gibson, area vice president and managing director for Hilton Hawaii. When completed, the expansion will create about 700 permanent hotel jobs, he said.

Construction on the first timeshare tower — a 37-story building with 300 rooms — is expected to begin in 2013. Work is expected to be completed by 2015. Construction on the second tower, with 25 floors and 250 rooms, is scheduled to begin by 2010, he added.

Hilton decided to devote all the new units to its timeshare pool based on the success in recent years with other timeshare projects, including the Grand Waikikian, which opened in late 2008 at the Hilton Hawaiian Village, Gibson said.