The beach in front of the lot may not be there in twenty years
Coastal erosion is slow, unmapped on any hazard report, and it permanently removes land. Here is how to read a shoreline before you buy behind it.
CheckHazard//4 min read
Storm surge floods a coast and then leaves. Coastal erosion removes the coast and does not give it back.
It is slower, less dramatic, and for a long-term property decision it can matter more. It is also not a layer on a hazard screening, so this one is entirely on you to check.
Wave energy. Waves move sand along a shore and take it offshore during storms. Some returns and some does not.
Sediment supply. Beaches are fed by rivers carrying sand to the sea. Dam a river, quarry its bed, or armour its banks, and the supply drops while the waves keep working.
Loss of natural protection. Mangrove, seagrass, and coral reef all absorb wave energy. Remove them and more energy reaches the shore.
Hard structures. A seawall protects what is behind it and often accelerates erosion in front of it and beside it. A groyne or a port breakwater traps sand on one side and starves the other.
Look at the trees. Coconut palms leaning seaward, or standing in the water, or with roots exposed, mean the shore has moved back past them.
Look for exposed foundations. Old concrete footings, steps, or slabs on the beach are the remains of something that used to be inland.
Look at the beach profile. A steep, narrow beach with a scarp cut into the back of it is an eroding beach. A wide gentle one is usually not.
Look for failed seawalls. Broken, undermined, or repeatedly patched walls tell you the wall is losing.
Look along the shore in both directions. Where sand is piled up on one side of a structure and scoured on the other, sediment transport is being interrupted.
Look at the vegetation line. Is there mature vegetation with an intact edge, or a raw cut face?
How far out did the shoreline used to be, and when?
Has any part of this property been lost?
Is there a seawall, who built it, when, and has it been repaired?
Has anything been built along the coast nearby: a port, a breakwater, a reclamation?
Has the river nearby been dammed, dredged, or quarried?
Are there old photographs of this beach?
Old photographs are the single best evidence. Families keep them, and a beach photograph from twenty years ago against the same view today settles the question in seconds.
If the shoreline moves, the relationship between your title boundary and the water changes, and there are legal rules about the strip along the sea. That is a matter for a Philippine lawyer and a licensed geodetic engineer, and it is worth resolving before you buy rather than after.
A hazard screening reports mapped storm surge, flood susceptibility, elevation, slope, and distances at a point. It does not track shoreline change, and there is no coastal erosion rating on the report. The LGU, DENR, MGB, and a licensed geodetic engineer are where that answer lives.
CheckHazard does not replace a professional geotechnical or engineering survey.