The floodwaters brought chaos to northern provinces just as authorities were declaring that some of the wildfires that had raged through southern coastal regions for two weeks had been brought under control.
Fifteen people were killed in the floods in Kastamonu province and two people died in Sinop, authorities said, adding that search and rescue operations were continuing.
More than 1,400 people were evacuated from the areas affected, some with the help of helicopters and boats, and about 740 people were being housed in student dormitories, the Disaster and Emergency Management Directorate (AFAD) said.
The deluge damaged power infrastructure, leaving about 330 villages without electricity. Five bridges had collapsed and many others were damaged, leading to road closures, AFAD added. Parts of the roads were also swept away.