SAN ANTONIO -

Early voting began Monday as voters across Texas headed to the polls to cast their vote in the state’s Joint Constitutional Amendment Election.

One of the more controversial measures on the ballot is Proposition 6, which would take $2 billion from the state’s rainy day fund and use it to bank roll municipal water projects.

Texas House Speaker and San Antonio Rep. Joe Straus was one of the first to vote in favor of Proposition 6.

”We've done a great job in this community and in the whole Edwards Aquifer area at managing a limited supply of water,” Straus said. “This will actually help produce new supplies of water.”

Straus said the projects will go through a vigorous application process before the three-member governor-appointed Texas Water Development Board decides which ones to invest in.

The state plans to recoup the money once the projects are online.

As Texans continue to grapple with an ongoing drought, supporters said the water projects will help meet the increase in demand that will likely come with the state’s population growth.

In 2011, voters approved approximately $6 billion for the state’s comprehensive water plan.

Opponents of Proposition 6 said that money should be more than enough.

“It's my understanding that $6 billion that was approved in 2011 remains untouched so this looks like it’s shaping up to be a political slush fund,” said Bob Martin, president of the Homeowner Tax Payer Association of Bexar County. “Somebody is going to have to pay that money back.”

Like voters, conservation groups are also split on Proposition 6.

Straus said the Sierra Club supports the measure, but Alyssa Burgin with the Texas Drought Project said rural cities could see their water supplies diverted to meet the demand of the state’s larger cities.

“Two years ago during some of the worst drought, we had $7.62 billion in agricultural losses. Texas can’t continue to sustain that,” Burgin said. “There is no new water. There's only the water we have now so we have to think about where we allocate water."

For a list of early voting poll locations, click here (PDF), or visit KSAT 12's Politics page.

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