East Anglia water situation: December 2025 summary
Updated 14 January 2026
Applies to England
© Crown copyright 2026
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East Anglia rainfall for December 2025 ranged from 69% to 113% of the long term average (LTA) for the month, with the wettest catchment being The Upper Bedford Ouse. The area soil moisture deficit (SMD) reduced by 11mm from November to December 2025. For the majority of rivers, the flow for December 2025, when calculated as an average for the month was greater than the flow for November 2025. River flows ranged between 37% and 138% of the LTA. Groundwater levels have continued to increase with the majority of sites reporting an increase from November 2025 to December 2025. Public water supply reservoirs within East Anglia finished December 2025 with levels ranging from 54% to 86% of full storage capacity. Two reservoirs Alton and Ardleigh ended the month with levels at or above their respective normal operating curves.
1. Rainfall
December 2025 rainfall totals across East Anglia ranged from 69% to 113% of the LTA for the month. The Upper Bedford Ouse recorded the highest rainfall totals of 72mm. Central Area Fenland and the North West Norfolk and Wissey catchments recorded the second highest rainfall totals of 51mm. The average rainfall across East Anglia for December 2025 was 47mm, which is 81% of the historic LTA and considered normal for the time of year. All catchments across East Anglia recorded normal rainfall in December 2025. Over the past 3 months’ rainfall has been approximately average with most months receiving normal rainfall. November 2025 was an exceptionally wet month with Central Area Fenland receiving 11mm of rainfall which is 196% of the LTA.
2. Soil moisture deficit and recharge
The SMD for East Anglia at the end of December 2025 was 17mm. The SMD has continued to decrease from November 2025 at 28mm following normal rainfall in December 2025. SMD across East Anglia ranged from 10mm to 40mm, with the Lower Bedford Ouse and Cam having the lowest soil moisture deficit in the East Anglia area.
3. River flows
Following average December rainfall in nearly all catchments, the majority of river flow report sites recorded increases in month mean flows from November to December 2025. Exceptions include the rivers Cam and Yare which saw a slight drop in flows from November to December. River flows ranged between, 37% and 138% of the LTA. Heacham recorded 37% of the LTA which is considered notably low for the time of year. The River Tove recorded 138% of the LTA which is considered above normal for the time of year. All other river flow report sites recorded normal or below normal flows for the time of year.
4. Groundwater levels
Groundwater levels have continued to increase with the majority of sites reporting an increase from November 2025 to December 2025. The majority of report sites ended December 2025 with groundwater levels categorised as normal or below normal for the time of year. Therfield Rectory, North Hertfordshire, continues to be atypical for the area, with above normal groundwater levels for the time of year. This is likely to be the result of a locally exceptional recharge season, with the September 2024 to February 2025 rainfall in the Upper Bedford Ouse catchment being the fifth wettest September to February rainfall total on record (1871 to 2025) for that catchment.
5. Reservoir stocks
Public water supply reservoirs within East Anglia finished December 2025 with levels ranging from 54% to 86% of full storage capacity. Alton and Ardleigh reservoirs ended the month with levels at or above their respective normal operating curves. Grafham, Abberton and Hanningfield reservoirs ended the month with levels below their respective normal operating curves.
6. Forward look
6.1 Probabilistic ensemble projections for river flows at key sites
The river flow projections for the Bedford Ouse, show a higher probability of normal to below normal flow for March 2026. This probability is similar for Ely Ouse, Ivel and Ouse flow projections for March 2026. The Kym shows a higher probability of normal to notably low flow for March 2026. River flow projections for June 2026 show an approximate 50% or greater probability of normal flows at most forecast sites. The Ely Ouse shows greater than 50% probability of normal to below normal flows for June 2026.
6.2 Probabilistic ensemble projections for groundwater levels in key aquifers
The groundwater projection maps for March 2026 shows a high probability of below normal, notably low and exceptionally low ground water levels at most forecast sites. The Therfield Rectory groundwater level is predicted to be normal to above normal by March 2026. The groundwater projections for September 2026 give a high probability of most forecast sites having below normal or lower groundwater levels. Therfield Rectory is expected to stay within the normal range for September 2026.
Author: Hydrology Team, hydrology-ean-and-lna@environment-agency.gov.uk
All data are provisional and may be subject to revision. The views expressed in this document are not necessarily those of the Environment Agency. Its officers, servants or agents accept no liability for any loss or damage arising from the interpretation or use of the information, or reliance upon views contained in this report.