The collision took place on Jackson Street, east of the Beacon Boulevard intersection, shortly before 7 p.m.
A North Ottawa Community Hospital ambulance transported the woman to Hackley Hospital in Muskegon.
Heidi Joanne Barr was crossing Jackson Street, from north to south, while riding in her wheelchair, said Grand Haven Public Safety Sgt. Josh Tomes. She was accompanied by her son.
It was dark at the time and the road was still wet from the afternoon rain.
The driver of the SUV said he was traveling west on Jackson when he suddenly saw the wheelchair.
“I slammed on the brakes and swerved, but still hit her,” he said. “I thought I killed her.”
The pedestrians were not using a crosswalk.
Tomes emphasized using crosswalks as required by law. Several of the crosswalks in Grand Haven have been made wheelchair accessible, he said.