EA Hydrology

EA Hydrology API

Environment Agency Hydrology API providing sub-daily river flow, level, and groundwater data for England. No authentication required.

Data Model

• Station — A monitoring station with geographic coordinates, river/catchment info, and associated measures. Identified by UUID.
• Measure — A specific time series at a station (e.g. daily mean flow in m³/s). Identified by a composite notation string.
• Reading — Individual data point with date, value, quality flag, and completeness indicator.

Key Parameters

• _limit — Max results returned (default varies, use 10-500)
• search — Free-text station name search
• observedProperty — Filter by parameter type (flow, level, waterLevel, groundwaterLevel, rainfall)
• _offset — Pagination offset

Gotchas

• Station IDs are UUIDs, not simple numeric IDs.
• Measure notation strings are long composite identifiers (station-uuid-parameter-period-unit-qualifier).
• Readings can have quality flags: "Good", "Suspect", "Unchecked". Filter accordingly.
• The completeness field indicates whether all sub-period readings were available.
• Search is case-insensitive and matches station labels (names).