San Francisco Mayor London Breed on Thursday announced she's come up with a detailed proposal for the $181 million available from a recently announced windfall of excess property tax revenue.

According to Breed's proposal, the money would fund programs for homelessness, affordable housing, behavioral health and street cleaning.

"Opportunities like this are rare, which is why it is so important that we make responsible investments that will make an immediate impact in helping our homeless population into shelters, creating new affordable housing for our low-income residents, and keeping our streets clean," Breed said in a statement.

"The voters have been very clear that this is their top priority," she said. "The majority of the total windfall money is already being distributed to important programs like transportation and schools. I think we should take advantage of this chance to address the housing and homelessness crisis we see everyday."

Breed's legislation, which is co-sponsored by Supervisor Malia Cohen, would direct $90.5 million toward affordable housing programs with the Mayor's Office of Housing and Community Development, with $42 million of that going toward building more affordable housing.

Another $90.5 million would fund homelessness, behavioral health and street cleaning programs over a four-year period.

The Office of the Controller announced the $415 million tax windfall last month, generated from San Francisco's property tax roll, which is the total assessed value of all real property and personal property owned in the city. The tax roll grew by 22 percent over the past two years to $260 billion from $212 billion, resulting in the windfall.

According to Breed's office, the remaining $235 million will go toward the San Francisco Municipal Transportation agency, the San Francisco Unified School District, the San Francisco Public Library, street and tree maintenance, as well as programs for families and children.