Methodology
WaterAgent looks up the selected point in each loaded layer and groups what it finds into five evidence families: regional water-storage trend, climate, terrain, geology and aquifer, and wells and monitoring points. Raster layers are read from the grid cell containing the point, so a value describes that cell, not the exact spot. The coverage label is assigned by fixed rules. “Broad evidence coverage” requires both local families and at least one regional family; “No evidence coverage” means no family is available; anything in between is “Partial evidence coverage”. No score, probability, depth or yield is calculated, and the families are not weighted.
How each input was obtained
Every input is labelled with how it was obtained. A family takes the label of the most direct evidence available for it: measured before observed, observed before modeled. The label describes the kind of evidence, not its accuracy.
- Measured (in-situ)
- Measured in the ground at a known point: a well logged by the user. Such wells are user-reported and unverified.
- Observed (satellite)
- Observed by satellite and processed into a map: elevation, slope derived from it, and land cover.
- Modeled
- Estimated by a model or a blended product: rainfall (CHIRPS), topsoil texture (SoilGrids) and total water storage (GRACE/GRACE-FO mascons).
- Modeled (regional, ~5 km / 1:5M)
- A class taken from a continental map: the BGS depth-to-groundwater and productivity grids (cells of about 5 km) and the Africa Groundwater Atlas hydrogeology map (1:5,000,000). It describes a region and cannot describe a single parcel.
- Demo
- Synthetic example value, loaded in demo mode only.
- Missing
- Nothing is loaded for this input.
Regional aquifer maps
The Geology and aquifer family may be covered by two regional products: the Africa Groundwater Atlas hydrogeology map (1:5,000,000) and the BGS depth-to-groundwater and productivity classes for Africa (cells of about 5 km). They are shown as published, labelled “Modeled (regional, ~5 km / 1:5M)”, read from the map unit or cell containing the point, and never refined to the selected location. They give the regional setting and cannot describe a single parcel. They count toward coverage under the fixed rules, and the status text says so whenever the family rests on them alone.
Wells logged by the user
A well logged by the user within 2 km of the location counts as evidence for the wells and monitoring family. It is labelled “User-reported, unverified” wherever it appears: the values are as entered and have not been checked in the field. The water-table elevation is the ground elevation of the terrain cell minus the reported depth to water, so it carries the uncertainty of that cell average. Entries are checked for consistency and flagged, never corrected. The search radius and every check threshold are provisional — pending hydrogeologist review. Well coordinates are shown rounded to three decimals.
This label describes how much evidence exists for the location. It says nothing about whether water is present.