Great Eau
4 monitoring stations on this water in England, holding 1,361 values between 1968 and 2026. A named watercourse. The gauges below sit on it, at points its publisher records.
The monitoring network on this water
Hydrionis holds 1,361 values from 4 gauges on this water. Discharge is a property of a gauge and its reach, not of this water as a whole, so this page reports the network and its records rather than a single figure.
The seasonal shape
An annual mean says how much water a river carried. A monthly record says when — and on most rivers the difference between a wet winter and a dry summer is larger than the difference between one year and the next.
Taken as the publisher computes it rather than recomputed by Hydrionis from daily values: the publisher knows which of its readings passed validation. Months the gauge did not cover are absent rather than interpolated, and the line breaks where they fall.
What the shaded periods are (4 events)
A shaded period marks when something was recorded, not what caused the shape of the line. Where the two coincide, they coincided.
| Event | Type | Period | Standing | Authority |
|---|---|---|---|---|
| The 1976 drought | Drought declaration | 1975-05-01 – 1976-08-31 | Documented record | Compiled record |
| Yorkshire drought | Drought declaration | 1995-04-01 – 1996-03-31 | Documented record | Compiled record |
| The 2022 drought | Drought declaration | 2022-03-01 – 2022-10-31 | Documented record | Compiled record |
| European drought | Drought declaration | 2022-05-01 – 2022-10-31 | Documented record | Compiled record |
View the data behind this chart
| Period | Great Eau at Claythorpe (m³/s) |
|---|---|
| 1968 | 1.54 |
| 1979 | 0.422 |
| 1980 | 0.978 |
| 1981 | 0.999 |
| 1982 | 0.854 |
| 1983 | 0.943 |
| 1984 | 0.982 |
| 1985 | 0.799 |
| 2000 | 0.711 |
| 2001 | 1.34 |
| 2002 | 0.749 |
| 2003 | 1.52 |
| 2004 | 0.758 |
| 2005 | 0.568 |
| 2006 | 0.567 |
| 2007 | 0.584 |
| 2008 | 1.33 |
| 2009 | 0.907 |
| 2010 | 0.987 |
| 2011 | 0.735 |
| 2012 | 0.280 |
| 2013 | 1.51 |
| 2014 | 0.848 |
| 2015 | 0.818 |
| 2016 | 0.791 |
| 2017 | 0.576 |
| 2018 | 0.785 |
| 2019 | 0.389 |
| 2020 | 1.44 |
| 2021 | 1.29 |
| 2022 | 0.711 |
| 2023 | 0.648 |
| 2024 | 1.78 |
| 2025 | 1.35 |
| 2026 | 1.30 |
About this series
| Source | Environment Agency — Hydrology Data Explorer API · Open Government Licence v3.0 |
|---|---|
| How the values came to exist | Measured |
| Period held | 1968–2026 |
| Completeness | 59.3% of the periods in that span are held. Gaps are drawn as breaks and never interpolated. |
| Known gaps |
|
| Continuity | The record begins in 1968 and is not continuous from it: 59 years separate the first value from the last, and 59% of the years between them are held. The span is not the record. |
| Last read from the publisher | 2026-08-24 |
| Redistribution | Permitted by the upstream licences |
| Commercial reuse | Permitted by the upstream licences. No Hydrionis access tier can widen this. |
| Methodology | How this was produced |
Every gauge Hydrionis holds here
| Gauge | Measures | Values | Record |
|---|---|---|---|
| GREAT EAU | ept family richness, life flow index (family level), proportion of sediment-sensitive invertebrates, whpt average score per taxon, whpt number of scoring taxa | 405 | 1987–2026 |
| Great Eau at Claythorpe | mean river flow, mean monthly river flow | 401 | 1968–2026 |
| GREAT EAU | ept family richness, life flow index (family level), proportion of sediment-sensitive invertebrates, whpt average score per taxon, whpt number of scoring taxa | 355 | 1980–2021 |
| GREAT EAU | ept family richness, life flow index (family level), proportion of sediment-sensitive invertebrates, whpt average score per taxon, whpt number of scoring taxa | 200 | 1980–2026 |
How these gauges were attached to this water
Named by the publisher Each gauge here names this water in the publisher’s own station record. Hydrionis has not inferred the connection from station names.
| Gauge | Evidence | Established |
|---|---|---|
| GREAT EAU | Stated by the publisher on the record this gauge’s observations came from. | With the observations |
| Great Eau at Claythorpe | Stated by the publisher — Environment Agency hydrology station register, riverName field — https://environment.data.gov.uk/hydrology/id/stations | 2026-08-26 |
| GREAT EAU | Stated by the publisher on the record this gauge’s observations came from. | With the observations |
| GREAT EAU | Stated by the publisher on the record this gauge’s observations came from. | With the observations |
What this record holds
Hydrionis decides which waters get a page, and which of those are offered to search, from what is actually held rather than from how the page reads. Five signals are counted; this record has 5 of them, which makes it a full profile.
| Signal | Held | Counts |
|---|---|---|
| Gauges holding a real record | 4 | yes, 3 or more |
| Years spanned | 59 | yes, 20 or more |
| Values held | 1,361 | yes, 1000 or more |
| Distinct measurements | 7 | yes, 2 or more |
| Publishers measuring it | 2 | yes, 2 or more |
| Official identifiers | 1 | recorded, not counted |
Use this data
Use this data
- Machine-readable JSON
/api/v1/observations/by-subject/eco-ea-55123.json - How to cite this, and who you must credit
- How these figures were produced
- Request this at a different scale, format or geography
Attribution and citation
Attribution you are required to give
These are conditions of the licences the underlying data is published under. They are obligations to the publishers, not to Hydrionis, and they apply to you directly whether or not you mention Hydrionis at all.
Contains public sector information licensed under the Open Government Licence v3.0. Contains public sector information licensed under the Open Government Licence v3.0.
- Environment Agency — Open Government Licence v3.0 (licence text)
- Environment Agency — Open Government Licence v3.0 (licence text)
Suggested citation for Hydrionis
Hydrionis (2026), Great Eau gauge records, accessed 2026-09-02, hydrionis.com/waters/england-great-eau/
Cite Hydrionis where you rely on the compilation, the normalisation, the eligibility judgements or a chart. Where you use an unmodified published value, the publisher’s attribution is the one that is required; crediting Hydrionis as well is welcome and is not something Hydrionis can require of you.
Where these figures come from
Source: EA ecology — Ecology and Fish Data Explorer — freshwater macroinvertebrates, INV_OPEN_DATA_TAXA.csv. Licence: Open — attribution required (attribution required).
Method: Count of distinct mayfly, stonefly and caddisfly families in a standardised three-minute kick sample (method BT001). Every record is rolled up to its family through the Environment Agency’s own taxon dictionary before counting, because analysts identify to mixed ranks and counting raw taxa would measure the depth of identification. Records identified no further than the order are excluded.
Retrieved 28 August 2026.