Bloomberg via Getty Images Environmentalists say disposable plastic bags like these are one of the greatest threats to our waterways.

Californians voted Tuesday to uphold the landmark plastic bag ban that state lawmakers passed over two years ago.

Proposition 67 asked voters to either preserve or strike down the first-of-its-kind statute, which bans disposable plastic bags, requires grocers to charge at least 10 cents per recycled paper or reusable bag given to consumers and provides $2 million in competitive loans to help plastic bag producers convert their businesses into reusable bag manufacturers.

Plastic bag ban ordinances are already in place in more than 150 cities and counties across the state as part of an effort to cut back on landfill waste and waterway pollution. Similar bans have been enacted in several cities nationwide, but California is the first to enforce a statewide initiative.

The proposition qualified for the ballot in February 2015 following signature-gathering efforts by the trade group American Progressive Bag Alliance, which argued that the measure killed jobs in the plastics industry and that the California legislators who passed it wanted “to line the pockets of big grocers and their labor union supporters.”

The ban would have gone into effect in July 2015, 10 months after Gov. Jerry Brown (D) signed it and praised it as a crucial step toward ending “the torrent of plastic polluting our beaches, parks and even the vast ocean itself.”

Several major environmental groups, including the Sierra Club, Surfrider and Oceana, endorsed Prop 67. Its eco-conscious supporters point to reports showing that disposable plastic bags are a major source of litter in oceans and that hundreds of marine species entangle themselves in or ingest the bags.

But voters shot down Prop 65, a separate, somewhat conflicting ballot initiative brought forth by the APBA. It would have established a new state fund for environmental programs and redirected revenue from the carryout bag fees there instead of allowing grocers to keep it.

If Prop 65 had gained more “yes” votes than Prop 67, courts could have interpreted that as nullifying Prop 67 altogether, according to an analysis by the Legislative Analyst’s Office.

Advocates for the plastic bag ban criticized Prop 65 as an attempt by APBA to confuse voters. The alliance, however, said that was not the intention and that Prop 65 is meant to offer voters the opportunity to ensure any fees go toward protecting the environment.