SAN DIEGO -- Homeowners who live by Lake San Marcos said they are fed up because no one is doing anything to clean up the lake.

Some residents have said the lake is green, polluted and unhealthy to swim in.

Retired lawyer Margaret Konn knew she wanted to live in the area the minute she saw Lake San Marcos, but now she says she wouldn't dare touch the water.

"It smells; you can't even see the bottom. I wouldn't want to swim in it, that's for sure," said Konn.

It has been an issue many homeowners have dealt with for years.

"Everybody is using our lake as a dumping ground, and I'm tired of it," said Konn.

When the Konns moved near the lake three years ago, there were many birds on the lake. Now, they're hard to find.

Homeowners told 10News they blame it on the pollution.

The California Regional Water Quality Control Board said San Diego County, the cities of San Marcos and Escondido, the Vallecitos Water District and homeowners who live there contribute to the pollution.

Experts said an old landfill under a nearby park and numerous farms and dairies that once existed are also possible sources of the problem.

A formal study would help determine who should be responsible for cleaning up the lake, but it is on a long list of polluted water bodies and is not supposed to be inspected for several years.

The Environmental Protection Agency declared Lake San Marcos impaired or polluted seven years ago, but some homeowners said there is no time to waste.

"Nobody is taking any action, and you know it's about time our residents standing up and saying, this is enough; we're fed up, we're tired," said Konn.

The lake is privately owned by La Jolla Development Group, and the group said the state owns the water and the creek that feeds the lake.

The group said, "There are 40 years of blame to go around regarding the Lake San Marcos water quality … the best approach to this resolution would be a cooperative one versus a finger-pointing exercise."

Konn said the parties involved need to stop polluting.

"We want some action. We have to have safety nets, we have to have people more responsible and we have to have the governing bodies be more stringent," said Konn.

But some homeowners hoped their efforts would force agencies to speed up the process.

The California Regional Water Quality Control Board said agencies involved are trying to resolve the issue before lawsuits are filed.