AUGUSTA -- Dirt and gravel camp roads that lead to shorefront homes are slowly loading Maine lakes with pollution that's turning dozens of them green with algae and threatening hundreds more.

The challenge of fixing the problem, however, is proving to be daunting.

A legislative panel decided Tuesday to kill a plan that would have authorized towns to fix eroding private, lakeside roads by collecting fees from the property owners who use them. Instead, it sent the issue back to the Department of Environmental Protection for more research.

Lawmakers, environmental regulators, municipal officials and lakeside residents all agreed the problem is critical, especially with increasing waterfront development. But they could not agree on a way to pay for what will collectively be a massive environmental cleanup.

"It's insidious. It happens everywhere at once and it's very hard to see," said Maggie Shannon, executive director of the Maine Congress of Lake Associations. "It's a crisis, and it's time that we stop denying it."

While Shannon urged action, she also said the idea of collecting new fees from lakefront property owners to pay for repairs would pit those residents against town and state officials.

"It has the potential to set in opposition groups of people who have to work together," she said.

Private camp roads are considered one of the largest causes of declining water quality in Maine lakes.

Because they run downhill from main roads to lake basins, camp roads that aren't well designed and maintained can basically turn into culverts for rainwater.

On one hand, hard-packed camp roads can behave like pavement and carry polluted storm water right into a lake. On the other, they can erode and wash into the lakes over time, becoming a major source of sediment pollution in their own right.

The sediments carry phosphorous, a naturally occurring nutrient that feeds lake algae. The pollution first shows up as a muddier lake bottom, more algae growth and water that's not as clear as it used to be. And, when a lake gets enough phosphorous, the summer sun can trigger a thick, stinky algae bloom.

Maine has 32 lakes now considered to be impaired and in need of restoration because of runoff and phosphorous.

Another 239 are classified as at risk of joining that list because of development and erosion.

"We have experienced a tremendous explosion in land development in the watershed," said Keith Williams, a member of the Highland Lake Association in Windham and a supporter of the fee proposal.

Some organized lake associations have spent hundreds of thousands of dollars to fix roads and divert storm water, but still have not been able to restore water quality. There are state and federal grants, but generally not enough to rebuild or repair the roads, officials said.

Keeping the pollution out of the lakes is still far less expensive than trying to restore a lake that has been overloaded with phosphorous, said Bill Bell, executive director of the Maine Association of Soil and Water Conservation Districts.

Several waterfront landowners said the proposed solution unfairly singled them out.

"People like to point fingers at a shore landowner and don't want to contemplate all that storm water that comes from an urban area," said Maxine Pray of Winthrop.

Driveways, parking lots, boat ramps, trails and bridges also contribute to the problem, she said.

Many waterfront landowners are already angry with their towns because of huge property tax increases, and because towns have stopped maintaining the unpaved roads that for years were treated as town ways, they said.

"We don't want to get out of our obligation," said Patten Williams, president of the Togus Pond Association in Augusta. "We're just afraid a small group of people is going to be tagged with a huge cost."

The DEP will now go back to the drawing board and report to the Legislature in the next a session.

"We've been given an open ticket, basically to find out how else we can do this," said Don Witherill, watershed management director for the DEP.