Sinking Brick Pavers & Sea Wall on Florida Barrier Island: Subsidence & Moss

Question: Delray Beach, FL: red brick pavers around pool/patio sinking unevenly after 7 years. Sea wall on canal. What maintenance? Why do pavers sink? Also, why moss/mold between bricks in sandy, hot conditions?

Answer: Subsidence from Drained Everglades; Consult a Civil Engineer/LA

Area built on drained Everglades—sandy, salty, low water table—prone to subsidence (soil movement). No quick fix. Hire a FL-licensed civil engineer or landscape architect ($100–$200/hr) to assess if structures are creeping toward waterway. Solutions: pilings, ground screws, sheet piles, redirect water, fill voids. USGS subsidence info.

Moss/mold: Spores land everywhere; they thrive warm & moist. Remove with bleach/soap solutions (watch for slippery residue). Create hostile environment: improve drainage, increase sun/airflow.

—Marc