East Anglia water situation: August 2026 summary
Updated 14 October 2026
Applies to England
© Crown copyright 2026
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1. Summary
East Anglia rainfall for September 2026 ranged from 36% to 76% of the long term average (LTA) for the month. Across East Anglia this was the driest April to September period to date (1871 to 2026), receiving 48% of the LTA. Soil moisture deficit (SMD) has increased in all catchments. River flows have continued in an overall downwards trend, some showing a sharp but short recovery period towards the start of the month during which most rainfall was received. Month mean flows were predominantly below normal or exceptionally low for the time of year. Groundwater levels continue to decline, with the majority of sites recording below normal to exceptionally low levels for the time of year. Anglian public water supply reservoirs ended September 2026 with levels ranging from 53% to 81% of full storage capacity.
2. Rainfall
An average of 30.4mm of rain fell across East Anglia in September, 58% of the LTA. The month started with predominantly dry weather with some short rainfall events, before transitioning to persistent dry conditions for most of the remaining month. Most rainfall was received between 3 and 13 September. The highest rainfall totals were recorded in the southern areas, North Essex and South Essex receiving 69% and 76% of their LTAs respectively. The lowest rainfall total was recorded in North Norfolk which received only 36% of the LTA.
Over the past 6 months, all hydrological areas in East Anglia recorded exceptionally low rainfall. The total rainfall for East Anglia in the 6 months from April 2026 to September 2026 was 155mm, ranking as the driest 6th month April to September period on record. Over the past 6 months, East Anglia has received 48% of the LTA rainfall.
3. Soil moisture deficit
The SMD for East Anglia at the end of September 2026 was 121mm. The SMD increased sharply at the start of the month following the sudden reduction experienced with the rainfall at the end of September. Most hydrological areas in East Anglia recorded SMD levels between 101mm and 130mm, with the exception of South Essex and Cam which both recorded SMDs of 131mm to 160mm. The SMD was 26mm to 50mm greater than the LTA at the end of the month for all hydrological areas with the exception of South Essex which was 6mm to 25mm greater.
4. River flows
Daily mean river flows continued an overall recession through September, with some rivers showing a sudden, though short, period of recovery with rainfall early in the month. Monthly mean river flows varied across East Anglia during September, ranging between 27% and 83% of the LTA. Most flow monitoring sites reported notably low or exceptionally low monthly mean periods for the time of year. The lowest flows were found towards the central and south-eastern areas, while the western catchments of the Upper Bedford Ouse and northern catchments of North West Norfolk closer to expected rates.
5. Groundwater levels
Groundwater levels continued to fall across all of East Anglia in September as a result of low rainfall. More than half of our groundwater sites for which data is available recorded below normal to exceptionally low levels for the time year. Sites reading normal levels are mostly found at the south end of the area. No sites are holding above normal levels for the time of year anymore.
6. Reservoir stocks
Reservoir storage has continued to fall through September, with all reservoir levels below their target curves for the time of year. Storage capacity ranged from 40% capacity at Hanningfield to 59% capacity at Ardleigh reservoir.
Author: Hydrology Team, hydrology-ean-and-lna@environment-agency.gov.uk
Contact Details: 03708 506 506
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.