A Washington state woman working on her above-ground swimming pool was swept down a ravine Monday when the pool suddenly burst.

The woman was performing maintenance on the backyard pool when it gave way, Tacoma Fire Capt. Todd Magliocca said.

The resulting wall of water from the estimated 5,000-gallon pool swept the woman 30 feet down a gully.

The tree-filled ravine abuts the home’s backyard. The wave carried woody debris with it that ended up on top of her, Tacoma Fire spokesman Joe Meinecke said.

“We had to unlayer the debris,” Meinecke said.

Fire crews pulled the woman out of the gully using a litter and ropes. Magliocca characterized the rescue as “very difficult.”

The victim has been transported to a hospital with unknown injuries. She was conscious during the rescue, fire personnel said.