The first Tahoe Summit began between President Bill Clinton and Vice President Al Gore in 1997. Since then, $1.5 billion has been spent on measures designed to keep the lake waters clear.
But there's a problem: Silt in the lake is on the rise, and the money's running out.
Senator Dianne Feinstein laid out the accomplishments of the past 15 years at Monday's summit.
"We have installed erosion control measures on 501 miles of roadways throughout the Tahoe basin," said Feinstein.
Twenty-four square miles of wildlife habitat has been restored. Boat inspections have prevented the infestation of invasive mussels. And water filtering of storm water runoff along with fire protection measures have kept silting down.
The federal government authorized $300 million in federal spending in 2000, and Senator Feinstein has said she's working with Nevada's senators to reauthorize that expenditure, but she's asking local businesses and homeowners to kick in $300 million more.
"If you're a homeowner here, you have a vested interest to see that this lake is healthy," said Feinstein, "to see that it's not occluded, to see that the clarity remains. To see that your house doesn't burn down."
Along the shore, some residents say they would help, while others were skeptical, and yet some others said the need isn't that great.
"I would like to know why we're losing clarity in the water, and not just jump to some $300 million solution," said San Jose resident Richard Rock.
"There is no magic bullet there," said Governor Brown when asked what the state could offer in terms of funding. "There is no Santa Claus. There is no bag of tricks."
Brown's best hope is the economy in California will turn around again. In the meantime, Brown signed an agreement on Monday with Nevada's governor to develop an updated regional Tahoe plan by the end of next year.
"I've talked to the Nevada governor. I think he's got an open mind," said Brown. "I have an open mind. I like development. It's got to be the right kind of development, but I also like getting to the point, getting to the conclusion."
Nevada had been threatening to pull out of the Tahoe Regional Planning Agency. The agreement to develop a regional plan by the end of next year keeps everyone on board for now.