Bay Area voters approved a first-of-its-kind tax to fight the effects of climate change.

Measure AA, which passed with 69 percent of the vote during California’s primary on Tuesday, will impose a new annual property tax of $12 per parcel. The funds raised — an estimated half billion dollars over the next 20 years — will be used to restore tidal marshes around the San Francisco Bay to help mitigate flooding from rising sea levels and climate-related storms. Restoring the wetlands will also provide habitat for migrating birds and other wildlife, as well as help to reduce pollution in the area.

Some opponents said the flat rate was unfair because it taxed everyone at the same level, regardless of income or resources. “Whether it is a struggling farm worker family in a very modest bungalow in Gilroy, or the Apple campus there in Silicon Valley,” the tax is the same, Jon Coupal, president a local taxpayers advocacy group, told NPR in May.

But proponents of the measure argued that a $1-a-month tax was not too onerous, and the benefits to the region would be many. Environmental groups including the Sierra Club, the Environmental Defense Fund, and the Nature Conservancy endorsed it as a way to protect the Bay Area from climate change.

Grist thanks its sponsors. Become one.

About 80 percent of the Bay’s marshes have already been lost to development, KQED reports. One study estimates there is $62 billion worth of property at risk from climate change in the Bay Area, including developments like the Facebook and Google campuses and the San Francisco ferry terminal. The passage of this measure could help change that. Here’s hoping.