HydrionisGlobal Water Intelligence
Solutions

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.

Asset planners, resource managers, regulatory reporting teams698,314 relevant observations
698,314
Observations available
3
Relevant datasets
1836–2026
Period covered
3
Commercially reusable

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 ingested. Newer gauges in the Environment Agency network are not held.

Go to the data →

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.

Go to the data →

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.

Go to the data →

Relevant datasets

DatasetObservationsCoverageLicence
England River Flow Dataset255,7371879–2026Commercial use permitted
England River Water Quality Dataset252,8572000–2025Commercial use permitted
England Groundwater Level Dataset189,7201836–2026Commercial use permitted

Key measures

Full dictionary →
MeasureDefinitionUnit
Mean river flowAverage volumetric discharge past a gauging station over a stated period.
Flow is a property of a specific gauge on a specific reach, and cannot be attributed to a river as a whole. Two gauges on the same river can differ by an order of magnitude. Where a station measures flow through a sluice, lock or pumping station — much of the Dutch network does — discharge is signed and a negative value means water moving in the reverse direction, which is a real operating state and not an error. Managed flow of that kind is not comparable with discharge at a natural gauging station, because it reflects operational decisions as well as hydrology.
m³/s
Groundwater levelElevation of the water table or piezometric surface at a monitoring borehole.
Levels are specific to a borehole and its aquifer, and must be read against that borehole’s own historic range. Absolute elevations from different boreholes are not comparable.
m
LeakageWater lost from the distribution network and from customer supply pipes through physical escape, expressed as a daily volume.
Absolute leakage scales with the size of the company, so it must not be used to rank utilities of different sizes. Use litres per property per day or leakage per kilometre of main for comparison.
Ml/d
Annual precipitationTotal depth of precipitation falling over a defined area in a calendar or water year.
Annual totals for different countries are not comparable as a measure of water availability. A large arid country and a small wet one can have similar national average rainfall while having entirely different renewable water resources per person. Gauge networks also differ in density, and mountain precipitation is systematically under-measured.
mm

What Hydrionis does not hold for you

Access

Everything referenced here is available through the JSON API and, where the source licence permits redistribution, as CSV extracts. Field definitions are in the data dictionary.

For bulk extracts, higher-volume API access, commercial licensing or bespoke work, see data enquiries.

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