Wessex water situation: April 2026 summary
Updated 13 May 2026
Applies to England
© Crown copyright 2026
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This publication is available at https://www.gov.uk/government/publications/water-situation-local-area-reports/wessex-water-situation-april-2026-summary
1. Summary
April 2026 continued the dry weather experienced in March with an average of 19mm falling in Wessex, 32% of the long term average (LTA). The majority of days were dry with the main rainfall recorded on 15 April. The past 2-month period across the Wessex region has been the 12th driest March and April on record and fifth driest for the Poole Harbour and Purbeck area.
Soil moisture deficit (SMD) rose in April in response to the low rainfall and is now at a similarly high level to 2025. Monthly mean flows were mostly below normal across the north of Wessex but predominately normal for those locations in the south which are supported by the Chalk aquifer. The Bristol Frome at Frenchay is reported as exceptionally low monthly mean flows.
Groundwater levels in Wessex fell during April. At the end of April most groundwater sites, including those on the Chalk aquifer recorded normal levels. The exceptions to this are Didmarton (monitoring the Inferior Oolite) which recorded notably high levels and Chipley (monitoring the Otter Sandstone) which recorded below normal levels.
Overall reservoir levels for Wessex Water were approximately 94% capacity at the end of April while for Bristol Water, levels were approximately 93% capacity.
2. Rainfall
An average of 19mm rain fell across Wessex in April (32% of the LTA). Most days in April were dry. Rain fell mostly towards the middle of the month with the largest rainfall event occurring on 15 April. Most hydrological areas in Wessex received notably low rainfall with only 4 exceptions. These areas are all in the north of Wessex and received below normal rainfall in April. The lowest cumulative rainfall was recorded in Poole Harbour and Purbeck which received 12mm (20% LTA). The highest relative rainfall was recorded in the Yeo and Kenn area which received 27mm (46% LTA). The past 2-month period across the Wessex region has been the 12th driest March and April on record and fifth driest for the Poole Harbour and Purbeck area. Despite a drier than average March and April in the past 3 months most hydrological areas in Wessex received normal rainfall. In the past 6 months the majority of hydrological regions recorded exceptionally high rainfall. Over the past 12 months, hydrological areas to the north of Wessex received normal to above normal rainfall. In the south of Wessex, hydrological areas received above normal to notably high rainfall.
3. Soil moisture
SMD has risen across the Wessex region in response to the low rainfall and is now at a marginally higher level than in 2025 and close to the historic maximum. At the end of April, most hydrological areas recorded an SMD of between 41mm and 70mm. Some catchments in south Wessex recorded a greater SMD of between 71 to 100mm. SMD at the end of April (reported up to 28th April) was between 26mm to 50mm greater than the LTA for most hydrological areas. The exception to this was the Mendips and River Chew area which recorded a SMD between 6mm to 25mm greater than the LTA.
4. River flows
In April river flows fell across the entire Wessex region in response to the drier weather. Most flow monitoring sites in the north recorded below normal monthly mean flows with the Bristol Frome at Frenchay reporting as exceptionally low. In contrast the majority of monthly mean flows were normal in the south of Wessex due to the supporting baseflow from the Chalk aquifer. River flows for both surface water and groundwater dominated catchments have fallen steadily across the month with surface water catchments responding temporarily to rainfall around 15 April.
5. Groundwater levels
Groundwater levels fell across all of Wessex in April in response to the low rainfall. At the end of the month most monitoring sites reported normal levels. In the north, groundwater levels at Allington and Didmarton (monitoring the Greater and Inferior Oolite respectively) both fell steadily across the month but Didmarton is still reporting notably high levels. Groundwater levels in the west and south of Wessex, including in the Chalk aquifer, fell throughout April with Chipley (monitoring the Otter Sandstone) reporting below normal levels by the end of the month.
6. Reservoir stocks
Both Wessex Water and Bristol Reservoir levels have fallen through April though remain higher than in 2025. The combined levels at the end of the month for Wessex Water were approximately 94% capacity. For Bristol Water the combined levels were approximately 93% capacity.
Author: Wessex Hydrology, hydrology.wessex@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.