The Lower Colorado River Authority says the recent rainfall we've gotten is more than Lakes Buchanan and Travis can safely hold.
So last week the LCRA started moving water downstream through the system by opening floodgates at the dams in the area.
"This the first time since 2007 we've had the need to open a Mansfield Gate dam. And so it's a very significant day that Lakes Buchanan and Travis are full," said Phil Wilson the General Manager of the LCRA.
Wilson says they're releasing the water in a safe, gradual way. Mansfield will be open for 48 hours.
"The dams and the lakes work the way they're supposed to work in times of drought. We capture that rain, we keep and protect the integrity of the water supply. In times of plenty you want to ensure you keep the lakes full but make sure you don't overflow them that way," Wilson said.
A decade is a long time. So a big group of people gathered to watch Monday morning. Beth Jones from Cedar Park brought her 12-year-old son Christopher and his friend Daniel. They were too young to remember the last time water came from the Mansfield Dam.
"I thought it would be neat for the kids to see that because we get to see the lake a lot to see how it empties and how it re-generates. I thought it would be fun for them," Jones said.
Tom Miller Dam will also continue floodgate operations and hydroelectric generation.
A word of caution if you're going to be out on the lakes: The fire chief has closed Lake Austin from Walsh Landing to Tom Miller Dam and Lady Bird Lake from Tom Miller Dam to Red Bud Trail.
The closures will remain in effect as long as the floodgates are open.