{"service":"usgs-nwis-proxy (shared)","usage":"/?bbox=west,south,east,north","params":{"bbox":"required: west,south,east,north (decimal degrees)","siteType":"ST (stream, default) | GW (groundwater) | ... NWIS site type code","siteStatus":"active | all (default active)","dataTypeCd":"iv,dv for stream gages; gw for groundwater (auto-selected by siteType)","siteOutput":"basic | expanded (expanded auto-selected for GW for well_depth + alt + aquifer)"},"returns":"{ bbox, count, gages: [...], source }","source":"USGS NWIS Site Service"}