SAN ANTONIO—Visitors of Natural Bridge Caverns are running into a unique opportunity over in New Braunfels, and it is all thanks to the heavy rain that has fallen in the area recently.

All those recent rains are forcing Natural Bridge Caverns to change up their tours just a bit.  Some of the caves are filled with more than 50 feet of water.

Natural Bridge Caverns is known for its large caves and hidden gems. A treasure themselves, they now have an extra jewel.

“This is a part of the cave where you normally don't see water here,” said Matt Carr of Natural Bridge Caverns.

Heavy rain across the New Braunfels area recently filled the Glen Rose aquifer deep below the caverns. The aquifer is so full, the excess water is pushing up from below and rain drops filter down from above.

“In the last hour to hour and a half, it's come up about a foot, foot and a half from the rain we got yesterday and the day before,” said Carr.

Guests are frequently told about the hidden aquifer. This is one of the rare times they really get to see it work. The water rose quickly. One portion of a trail is covered with about 15 feet of water.

The bottom most portion of that cave was filled with 50 feet of water. Some can fill with up to 70 feet of water.

“If we don't get any more rainfall, the water may start to go down and it can go down several feet in a day,” said Carr.

The water may be gone within a few weeks. In times of drought, it can be years before something like this is seen again. How long the water stays in the caves all depends on how much rain we get and how frequently we get

“The cave itself is here because the aquifer hallowed it out,” Carr said. “For us outside, the rain events can be traumatic, but for the cave, this is why the whole thing is down here.”

The last time water seeped into these caves was after the flooding rains of Memorial Day 2015.