Authorities say a Northern California woman on a rock-climbing outing lost her footing and tumbled 30 feet before she was rescued by helicopter. The Sacramento Bee reports Michelle Powell was out in the Sierra near South Lake Tahoe Sunday when she gave her dog a boost onto a ledge. The California Highway Patrol said the dog started sliding back, at which point Powell tried to push the dog back up. She lost her balance, fell backward and tumbled 30 feet. Her boyfriend used his cell phone to call for help. Highway patrol officers used a helicopter to rescue Powell. She was flown to a nearby hospital where she was treated for injuries.