It's unclear how the water became electrified.
Bianca Cruz, 15, and her sister, 23-year-old Tiffany Cruz were in the pool Saturday about noon when electrical current ran through the pool.
Monday, Tiffany described what happened when she heard her sister scream her name.
"Towards the middle of the pool, I kind of felt a wave go through my body and that's when I realized something was a little odd," said Tiffany. "Unfortunately my sister was already at the deep end, so at that point I just rushed to her as fast as I could and that's where the current was much stronger."
Julio Cruz, the girls' father, says he heard Tiffany scream and rushed out to see Bianca face down in the water.
"I ran and pulled my daughter from the pool," said Cruz. "I felt the shocks in my hands."
While Cruz was working on his daughter, his distraught wife called 911 for help.
Moments after the call, Garden Grove police officers Claudia Alarcon and Edgar Valencia arrived. Both performed CPR until paramedics arrived.
Julio Cruz says work was recently done on the pool. It is unclear what caused the electrical shock. The pool has an underwater light.
"[Bianca] is doing great," said Tiffany Monday. "We're very thankful and blessed to have her with us. And happy." Bianca was expected to return home Tuesday.