SAN FRANCISCO (KCBS)— San Francisco’s Board of Supervisors voted unanimously on Tuesday to ban the sale of bottled water on public property.

The legislation includes the sale and distribution of water in plastic bottles (21 ounces or less) on city property beginning in October and would go into effect for sales on streets and sidewalks by 2016.

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Hours before the vote, supervisors took the ‘Tap Water Challenge’ hosted by the San Francisco Public Utilities Commission and anti-plastic activists on the steps of City Hall.

The test lined up two glasses with bottled water and one with tap water. The challenge was to distinguish between them all.

Supervisor Eric Mar participated with one of his constituents. Mar said the tap water had a cleaner taste.

“It tastes like water,” Mar said.

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Supervisor David Chiu, who co-sponsored the ban with Mar, took the taste test as well. Both of them picked tap water over bottled water.

Mar said tap water had a cleaner taste.

“I think there’s a lot of misinformation that Hetch Hetchy water might have some contaminants, but it’s the cleanest best source of free beverage,” he said.

Chiu couldn’t really tell the difference, but said that just showed why there’s no reason to pollute the environment by buying bottled water.

“We want to talk about just how wasteful these plastic water bottles are. We end up distributing millions upon millions, tens of millions here just in San Francisco alone,” he said.

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The ordinance, which bans selling bottled water, also calls for more water filling stations around San Francisco to make the resource more readily available.