Find groundwater monitoring wells with the USGS monitoring-locations API

Steps

1. Query GET https://api.waterdata.usgs.gov/ogcapi/v0/collections/monitoring-locations/items to find well sites, filtering by site_type_code as documented in the collection schema.
2. Well-specific fields such as well_constructed_depth, hole_constructed_depth, aquifer_code, national_aquifer_code, and depth_source_code replace the old NWIS well_depth_va/hole_depth_va/nat_aqfr_cd/aqfr_cd fields.
3. Use the returned id field (agency_code + monitoring_location_number) as the monitoring_location_id filter on /field-measurements, /continuous, or /daily to pull that well's actual measurements.
4. There is no bounding-box/HUC/county filter on most collections - first query monitoring-locations for your area of interest, then reuse the returned IDs as a filter on the target data endpoint.
5. Check the collection's /schema page and the SwaggerUI OpenAPI docs to confirm exact field names before building a client, since the API is still evolving pre-v1.