Fort Pierce sits right on the water in a way few Florida cities still do: downtown runs along the Indian River Lagoon, the Fort Pierce Inlet opens straight to the Atlantic, and Hutchinson Island stretches across the water as the city's barrier-island front porch. The sea breeze that makes all of this so pleasant also carries a steady load of salt, and it doesn't stop at the beach: it drifts across the lagoon, over US-1, and well into the neighborhoods west of town. The chimney is usually the highest, most exposed thing on the house, so it takes that salt bath first and worst.
Salt is quietly brutal on the metal parts a chimney depends on. Chase covers rust from the edges and screw penetrations inward, caps corrode until their mesh crumbles, and damper hardware seizes up long before anyone notices. On the island and along the lagoon these parts can fail years faster than the same components inland, which is why a corrosion-resistant replacement (stainless or properly coated) is money well spent here. A correctly fitted chimney cap keeps rain, salt spray, and animals out of the flue, and a sound, correctly pitched chase cover solves most of what goes wrong with the framed-chase fireplaces common in newer construction.
Masonry feels the coast too. Salt-laden moisture works into brick faces and mortar joints, and the side of the stack that catches the prevailing sea breeze often weathers visibly faster than the sheltered side. None of this is a reason to avoid a fireplace in Fort Pierce. It's simply a reason to treat the chimney like the piece of marine-exposed equipment it actually is, with the inspection rhythm to match.