RAMONA, Calif. -- Firefighters rescued four dehydrated hikers and a dog Saturday, but were unable to save the group's second dog that died on a trail down to Cedar Creek Falls outside Ramona, a fire official said.

A man, woman, two teenage girls and two dogs had hiked more than two miles in temperatures topping 100 degrees to reach the waterfall, Cal Fire Capt. Daryll Pina said.

"They had a little water, but they didn't have enough," Pina said. "Three of them suffered heat exhaustion but the man was more OK. One dog didn't make it."

A U.S. Forest Service crew drove the group back up the hill, where a friend was going to meet them and get them home.

Pina said more than a dozen people were rescued, some by helicopter, along the same trails into the falls over the past four weeks because of the heat.

About 20 Community Emergency Response Team volunteers from the Ramona area, aware of the extreme heat forecast for today, posted themselves along one two-mile trail from San Diego Country Estates to the falls, and handed out bottles of water and Gatorade to hikers.

A Cal Fire engine crew from the San Diego Country Estates fire station positioned itself at the top of the trail, and a U.S. Forest Service crew set up near the bottom to help hand out the drinks, Pina said.

He estimated that 50 to 60 hikers made the trek to the falls, and that volunteers handed out about 14 cases of drink bottles.