The New York Yankees will announce detailed plans Wednesday for a new $800 million ballpark, which would be built adjacent to the current Yankee Stadium and could be ready by the 2009 season. The team has spent years planning the new stadium, which will have a capacity of at least 50,800 -- approximately 6,000 seats fewer than the current ballpark -- but could be expanded to about 54,000. It would be constructed in Macombs Dam Park, to the north of the current stadium, and financed by the team. Yankee Stadium, which opened in 1923, is the third-oldest park in use in the major leagues, younger only than Boston's Fenway Park (1912) and Chicago's Wrigley Field (1914). Yankee Stadium was renovated extensively in 1974-75, but the team has long desired a modern ballpark with more luxury suites and wider concourses. The stadium plan calls for the new ballpark to resemble the original Yankee Stadium in many of its details, and the dimensions of the playing field would be identical to the current ballpark. It would have 50 to 60 suites, up from 18 in the current stadium.