Officials at the North Carolina coast on Sunday declared a state of emergency in Dare County and ordered an evacuation of Hatteras Island at the Outer Banks, ahead of expected flooding from Hurricane Erin.

Local officials say they only order evacuations ahead of hurricanes when it’s necessary to protect the public.

A tropical storm watch has been issued and mandatory evacuations are underway along the coast of North Carolina, as Hurricane Erin approaches. Coastal flooding and massive waves could leave roads impassable for days.