Katie Gerhardt remembered when her parents’ Siesta Key properties sat so close to the Gulf that one parcel was entirely underwater and the other was barely dry.
During a violent storm in the early 1980s, she recalled, waves pushed wet sand into a rental home the family owned on the dry lot, leaving Gerhardt to scoop sandy muck out of the house for days afterward.
At the time, the Gulf lapped at the property’s edge. But over the years, sand accumulated through a natural process called accretion — first slowly, then more recently by as much as 7 feet per year…