If you live in Seattle or Spokane, Lake Chelan is your summer go-to spot. Best of all, few Californians know of it. But that's about to change.CHELAN, Wash. — Just say the words "summer at the lake" in certain company, and you'll get a wistful smile, possibly followed by stories about fishing contests, belly-flops, mosquito bites, campfire songs, sexual awakening, lingering regret, family feuds, winterizing expenses and the prospect that the mortgage interest tax deductions for second homes might someday be disallowed.