Hydrionis for water utilities
Long hydrological records for the catchments you abstract from, regulatory performance data for every company in England and Wales, and the water quality record for the rivers you discharge to — all with the source and method attached to every figure.
What you can answer here
How unusual was this year’s flow at the gauges above our abstraction points?
Monthly and annual mean flow for 356 English gauges, many running since before 1930, with each year placeable against the station’s own record rather than against a national average.
Where it stops: Only stations whose record opens before 1970 are collected. Newer gauges in the Environment Agency network are not held.
What has actually happened to groundwater in our resource zones?
Monthly levels at 409 long-record observation boreholes, in metres above Ordnance Datum, back to 1836 at Chilgrove House.
Where it stops: Levels are borehole-specific and are not comparable between boreholes. Hydrionis does not model aquifer storage from them.
How quickly do our aquifers actually respond to rainfall?
The lag between England-wide rainfall and borehole level, computed per site on departures from each series’ own seasonal cycle, across every long-record borehole with enough overlap to test. The spread between sites is months wide, which is the point: a national drought statement says little about any particular resource zone.
Where it stops: Every site is tested against an England-wide rainfall average rather than local rainfall, so a site whose local rainfall departs from the national picture shows a weaker association for reasons about the rainfall record rather than the aquifer. Abstraction moves a level too and is in neither series.
How does our leakage compare with the rest of the sector?
Reported leakage for the appointed water companies of England and Wales, on the regulatory basis Ofwat publishes.
Where it stops: Company-reported leakage uses the regulatory water balance and is not comparable with international non-revenue water percentages, which use a different denominator.
Relevant datasets
| Dataset | Observations | Coverage | Licence |
|---|---|---|---|
| England River Water Quality Dataset | 748,160 | 2000–2025 | Commercial use permitted |
| England River Flow Dataset | 255,739 | 1879–2026 | Commercial use permitted |
| England Groundwater Level Dataset | 189,904 | 1836–2026 | Commercial use permitted |
Key measures
Full dictionary →| Measure | Definition | Unit |
|---|---|---|
| Mean river flow | Average volumetric discharge past a gauging station over a stated period. | m³/s |
| Groundwater level | Elevation of the water table or piezometric surface at a monitoring borehole. | m |
| Leakage | Water lost from the distribution network and from customer supply pipes through physical escape, expressed as a daily volume. | Ml/d |
| Annual precipitation | Total depth of precipitation falling over a defined area in a calendar or water year. | mm |