A 20-year-old Riverside woman died after being swept away in a flood control canal in Riverside during Thursday’s storm, as officials kept busy rescuing at least 30 people throughout Riverside County, officials said.

Stacie Mills-Nichols died after she was caught in floodwaters about 6:30 a.m., Corona Police Department Detective Jason Waldon said in a written statement.

Rescuers conducting a swift water rescue first found and rescued a 35-year-old Riverside man in the area of McKinely Street and Sampson Avenue, he said. The man told officials that his girlfriend had also been swept down the canal.

Officials found the woman in the water near Rincon and Auburndale streets, about 5 miles west of where her boyfriend was rescued, and about 8 miles west of where she was first swept away, officials said.

Both the man and woman were rushed to a hospital, where Mills-Nichols was pronounced dead, Waldon said.

The man told police that he and Mills-Nichols had been living in the flood control canal in the area of Indiana Avenue and La Sierra Highway in Riverside, he said.

“With the rapidly rising water in the flood canal, they were swept away in what he described as ‘neck’-high flood waters,” according to Waldon. “The raging waters took (the man) and Mills-Nichols west through the canal from Riverside and into Corona, where a nearby citizen spotted (the man) in the flood canal and called 911.”

The swift water rescue operation was only one of dozens carried out by Riverside County first responders on Thursday.

At least 30 people were rescued from flood waters, the Riverside Press-Enterprise reported.

Several pets were also rescued, officials said.

” We would like to remind everyone to avoid flowing water and flooded areas during this rainy season, the Corona Fire Department said in a written statement. “Motorist should not attempt to drive through standing water.”