Research and analysis

Wessex water situation: January 2026 summary

Updated 17 February 2026

Applies to England

• Publication for Northern Ireland
• Publication for Scotland
• Publication for Wales

1. Summary

January 2026 was the second wettest on record for Wessex. An average of 190mm rain fell across Wessex, 200% of the long term average (LTA). After an initial dry period, rain occurred throughout January, with a particularly wet period during Storm Chandra when 33% of the month’s rain fell in 2 days. Monthly mean river flows responded, and are exceptionally high, notably high or above normal across the majority of Wessex. The River Wylye and Upper Hampshire Avon reported normal mean flows due to slower responding groundwater recharge from the Chalk aquifer. The majority of groundwater sites monitoring the Chalk aquifer are recording exceptionally high levels, largely in response to rainfall received during Storm Chandra. Groundwater sites in the north and west of Wessex are recording normal to notably high levels. Soil moisture deficit (SMD) decreased in January to between 0mm to 10mm at the end of the month and now meet the LTA for this time of year. Reservoir levels in Wessex have largely increased throughout January. At the end of the month, reservoir levels for Wessex Water were approximately 100% capacity and combined levels for Bristol Water were 99% capacity. Reservoir levels for Wessex Water and Bristol Water are in line with the LTA for this time of year.

2. Rainfall

January was the second wettest on record, an average of 190mm rain fell across Wessex (200% of the LTA). After an initial dry period, rain occurred regularly throughout January with the wettest period between 26 and 27 January due to Storm Chandra, when 33% of the month’s rain fell. The highest relative rainfall for January was recorded in the River Piddle which received 272mm rainfall (230% of the LTA). The lowest relative rainfall was recorded in Little Avon which received 119mm rainfall (141% of the LTA). The Evershot rain gauge in the Dorset Frome catchment recorded 293mm of rain during January (238% of the LTA at the gauge).

Over the past 3 months, all hydrological areas in Wessex have received notably high or exceptionally high rainfall. Over the past 6 months, the majority of areas have received notably high or exceptionally high rainfall, except for the Axe, Brue and West Somerset Streams which received above normal rainfall. Over the past 12 months, most hydrological areas received normal rainfall, except for West Dorset Streams, River Frome, River Piddle and the Middle Dorset Stour.

3. Soil moisture

Soil moisture deficit (SMD) decreased in January in response to recent rainfall. At the end of January all hydrological areas in Wessex recorded an SMD between 0mm to 10mm. SMD was within 5mm of the LTA across all areas in Wessex.

4. River flows

In January, river flows in Wessex responded to the rainfall, reporting exceptionally high, notably high or above across the majority of Wessex. The sites that reported normal monthly mean flows were the River Wylye and Upper Hampshire Avon. This is due to slower responding groundwater levels in the Chalk aquifer. The Tone at Bishops Hull and Dorset Stour at Hammoon both recorded their highest monthly mean flows on record for January. Daily mean flows peaked in the majority of Wessex on 27 January in response to the rain from Storm Chandra, however Great Somerford and Frenchay recorded lower mean flows as less rainfall was recorded in north Wessex for this period.

5. Groundwater levels   

Groundwater levels increased in response to heavy rainfall across the majority of Wessex. At the end of January, groundwater sites in Wessex were reported between exceptionally high and normal levels. The majority of groundwater sites monitoring the Chalk aquifer reported exceptionally high levels at the end of January and 4 of these sites recorded their highest levels at the end of January since records began. These sites were Chitterne Down, Oakley Industrial Estate, Delcombe and Woodyates. In the west of Wessex, the majority of sites reported between notably high and above normal. In the east, levels at Tilshead (monitoring the Chalk) increased quickly in January but are currently at normal as the site was recovering slowly from low levels last year. Groundwater levels at Allington (monitoring the Great Oolite) have increased throughout January but remain normal as less rainfall was received in north Wessex during Storm Chandra. 

6. Reservoir stocks

Both Wessex Water and Bristol Water reservoir levels remain at or near capacity in January. The combined levels at the end of the month for Wessex Water were approximately 100% capacity, while for Bristol Water, combined levels were approximately 99% capacity. For Bristol and Wessex Water, these levels are typical for this time of year.

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.