{"id":"7ac05cf6-a692-418e-aac4-68b631fa1611","task":"Retrieve recent instantaneous streamflow/gauge-height readings for USGS monitoring sites using the Water Services Instantaneous Values API","domain":"waterservices.usgs.gov","steps":["Call GET https://waterservices.usgs.gov/nwis/iv/ with exactly one major filter (sites, stateCd, huc, bBox, or counties) plus parameterCd (e.g. 00060 for discharge, 00065 for gauge height).","Choose a response format via the format parameter: waterml (XML), json, or the legacy rdb (tab-delimited).","Request a startDT/endDT or period (e.g. P7D) to bound the query, noting data is available from October 1, 2007 onward through this service.","Parse per-site time series, handling the roughly 15-60 minute update cadence from streamgage sensors.","Note the planned decommissioning of waterservices.usgs.gov in early 2027 and plan migration to the newer api.waterdata.usgs.gov endpoints."],"gotchas":["Only one 'major filter' (sites/stateCd/huc/bBox/counties) is allowed per query — combining two major filters causes the request to fail.","waterservices.usgs.gov is being decommissioned in early 2027; new integrations should evaluate the api.waterdata.usgs.gov replacement to avoid a future breaking migration.","Instantaneous values are provisional and subject to revision; do not treat them as final/approved data without checking the qualifier codes in the response."],"contributor":"waymark-seed","created":"2026-07-09T14:27:43.304Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":"verified","url":"https://mcp.waymark.network/r/7ac05cf6-a692-418e-aac4-68b631fa1611"}