Elevation & Slope

Two numbers sit underneath almost every other hazard: how high your lot is above sea level, and how steep it is. They are quiet, but they drive how deep flood water gets, how well rain drains away, and how much foundation engineering your build really needs.

This layer reports both, sampled from satellite elevation data at your exact coordinate. On their own they are simple facts; combined with the flood, landslide, and liquefaction layers, they explain why a property behaves the way it does.

A low, flat lot near the coast collects water and is more likely to liquefy. A steep lot drains fast but raises landslide and foundation concerns. The same hazard map reads very differently depending on these two numbers.

Buyers rarely ask for elevation, yet it often explains the whole story: why one street floods and the next one over stays dry is frequently just a meter or two of height.

Elevation and slope are sampled from the SRTM (Shuttle Radar Topography Mission) 30 m global elevation model, the public-domain dataset used in research worldwide.

In production we read from resampled grids (100 m elevation, 50 m slope) that were validated against the native 30 m data across 100 Philippine test points, keeping the answer fast without changing what a reader sees.

Elevation comes from OpenTopography's SRTM GL1 30 m product, which is in the public domain.

Slope is computed from the same elevation surface. Because elevation and slope feed flood depth, landslide, and liquefaction, this layer is the quiet backbone of the report rather than a standalone alarm.