The record pace of 100-degree days in Austin has led to power grids laboring to cope with uncommonly high electricity usage to keep buildings cool.

But another method of keeping cool is on pace for records this summer: visits to Barton Springs Pool.

In 2009, the pool logged a record number of visits, with more than 350,000 coming in June, July and August. By comparison, the pool had more than 308,000 visitors in June and July this year.

"I would be shocked if we don't break that record," said Wayne Simmons, aquatics programs coordinator for the city's Parks and Recreation Department.

The attendance figures for the pool don't include those who frolic for free in the pool's spillway, as several dozen people were doing Saturday afternoon.

In years when creeks dry up, such as this year, the pool usually sees an increase in visits, Simmons said. This year, the drought has combined with an economy that is keeping more people in town and a record heat wave to bring more than just an uptick of visits, Simmons said.

On Saturday afternoon, a line of more than a dozen cars stretched to Barton Springs Road from the parking lot entrance for the pool, and about 100 people waited in line to enter. Inside, hundreds of people were swimming, wading and lounging under trees on the hillside next to the pool.

One Austinite said she's been bringing her children to the pool more than usual this summer because it's been so much hotter than usual.

Terri Rose, 48, said she usually goes to Lake Travis in addition to Barton Springs but that low water levels have made the lake less appealing.

The cooler temperatures in the pool compared with those in lakes brought Rusty Stratton, 25, also from Austin. Barton Springs Pool is usually in the vicinity of 70 degrees, whereas Lake Travis is usually in the upper 80s.

"I get in till I'm cold, then get out till I'm hot — and just repeat that process," Stratton said.

Parking is free during the week and $3 on weekends. Daily admission to the pool is $1 for children and seniors, $2 for juniors (ages 12-17) and $3 for adults.

Saturday's high of 104 at Camp Mabry was the 53rd day of triple-digit heat in Austin this year, and Travis County remains under a heat advisory until tonight.