By Laura Haefeli

MARYSVILLE (CBS13) – Mary Robertson said she’s lucky to be alive. Last Friday, after donating blood, she passed out behind the wheel of her car and crashed into Ellis Lake in Marysville.

Donating blood is something she’s done plenty of times before.

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“To help other people who need it,” Robertson said.

Robertson, 19 said she took the day off from work to give a little of herself to help someone else.

“I thought it was a good thing to do,” she said.

But her 9:00 a.m. donation didn’t go as planned.

“After I donated blood, I wasn’t feeling well and I almost passed out,” she said.

Robertson said employees at Vitalant in Marysville offered her snacks and a seat.

“I sat in the chair maybe 30-45 [minutes]. Almonds and goldfish and I think orange juice. It was pretty good.” she said.

Robertson said she felt better, so she decided to drive home.

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“It was three minutes away from where I lived so I thought I could keep driving and be fine,” she said.

But when she reached Ellis Lake everything went dark.

“I passed out. I felt like I blinked and all of a sudden I woke up in the middle of the lake. I woke up because the water was really cold on my feet,” she said.

Robertson said she was able to crawl through her window and swim to shore.

“I could have been dead in the lake,” she said.

Mary was sent to the E.R. as a precaution, where doctors confirmed the accident was caused by her blood donation.

“If you don’t feel well after donating blood, make sure you call someone to pick you up because donating blood is a good thing to do,” Robertson said.

CBS13 did reach out to Vitalant who tells us they do have rigorous safety practices in place for all donors including a pre-donation health assessment.

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They do require donors to eat at least two hours before the appointment, be a certain weight, and of course, you can’t be under the influence.