Research and analysis

Water situation: October 2024 summary

Updated 12 December 2024

Applies to England

October was another wet month across England with more than three quarters of hydrological areas receiving above long term average (LTA) rainfall for the time of year. Soil moisture deficits (SMD) remained low across much of England, and soils in many regions remain wetter than would be expected for the time of year. Monthly mean river flows increased at almost all sites in October, with more than three quarters of sites classed as above normal or higher. Groundwater levels increased at half of our indicator sites at the end of October, and over three-quarters of sites were classed as notably high and exceptionally high. Reservoir stocks increased across England and ended October at 86% full.

1.  Rainfall

The rainfall total for England for October was 91mm which represents 119% of the 1961 to 1990 LTA for the time of year (101% of the 1991 to 2020 LTA). More than three-quarters of hydrological areas received above average rainfall during October. The wettest hydrological area was the Tweed in north-east England which received 127mm of rainfall which is 186% of the LTA. In contrast, the Upper Dee in north Wales was the driest hydrological area having received just 60% of LTA rainfall (105mm) in October.

October rainfall totals were classed as normal or higher in all except two of the 139 hydrological areas we report on. One hundred and twenty hydrological areas (86% of the total) were normal for the time of year, and 17 were classed as being above normal for the time of year. The 2 hydrological areas which were classed as below normal for October were Upper Dee and North Norfolk. At the regional scale rainfall was classed as normal for the time of year in all regions and for England as whole.

The 3-month cumulative totals were mostly normal in east and north-east England, while the rest of England saw cumulative totals classed as above normal or higher in many places. This was particularly true in the south-east where cumulative rainfall totals were exceptionally high in many catchments due to the very wet weather in September. This pattern can be seen in the last 6 months too, although rainfall totals in the north-west were generally above normal or higher over this period. In the 12-month cumulative totals, almost all catchments are classed as having received exceptionally high rainfall, as England as whole has been the wettest on record for the period November to October since the start of the record in 1836.

2.  Soil moisture deficit

As would be expected at this time of year, and helped by another month of above average rainfall, SMD remained low across much of England although some small deficits remain in east England.

Soils continue to be wetter than expected in many regions across England, with only the north-west seeing SMD around average for the time of year.

3.  River flows

Monthly mean river flows increased at all indicator sites except 2 in October. More than three quarters of sites had monthly mean river flows classed as above normal or higher for the time of year. Ten sites had monthly mean flows classed as normal for the time of year, while the River Derwent at Ouse Bridge in the north-west was the only site to record below normal monthly mean flows.

Twelve sites recorded their highest October monthly mean river flow on record (record start given in brackets), including:

• River Nene at Upton Mill (1970) in east England
• The rivers Ver (1956), Leach (1972) and Kennet (1972) in south-east England
• River Avon at Bathford (1969) and Great Somerford (1963) in south-west England
• The Hampshire Avon at East Mills (1965) and Amesbury (1965) in south-west England
• River Frome (1965) and Upper Brue (1964) in south-west England

All regional index sites saw an increase in monthly mean river flows in October compared to September. Of the 7 regional index sites, 3 were classed as above normal, one was notably high and 2 were exceptionally high for the time of year. At Caton on the River Lune in north-west England, monthly mean river flows were classed as normal for the time of year, the only site in this class. In south-east the River Thames at Kingston had naturalised monthly mean flows classed as exceptionally high for the time of year. The River Ouse at Offord in east England was also classed as exceptionally high after recording its highest October monthly mean flow on record since records began in 1972.

4. Groundwater levels   

At the end of October, half of our indicator sites saw an increase in groundwater levels. All groundwater indicators sites were classed as normal or above for the time of year, with almost half classed as exceptionally high. Three sites recorded their highest end of October groundwater level on record (record start given in brackets), including:

• Weir Farm (1983) in Bridgnorth Sandstone in central England
• Coxmoor (1990) in Idle Torne Sandstone in central England
• Stonor Park (1961) in the south-west Chilterns Chalk in south-east England

Groundwater levels increased at 6 of the 8 regional groundwater sites, with just 2 sites continuing to decline. In south-east England, Jackaments Bottom in the Burford Jurassic Limestone and Stonor Park in the south-west Chilterns Chalk were both classed as exceptionally high for the time of year. Groundwater levels remain high in sandstone aquifers with Skirwith in the Carlisle Basin Sandstone notably high for the time of year, and Weir Farm in the Bridgnorth Sandstone exceptionally high at the end of October. Both Chilgrove (Chichester Chalk) in south-east England and Dalton Estate Well (Hull and East Riding Chalk) in north-east England were classed as normal for the time of year. In contrast, Little Bucket in the East Kent Stour Chalk in south-east England and Redlands Hall in the Cam and Ely Ouse Chalk in east England were notably high for the time of year.

5. Reservoir storage

During October reservoir storage increased at three-quarters of the reservoirs and reservoir groups that we report on. The largest stock increases were in the Derwent Valley in central England, Ardingly in south-east England and Clatworthy reservoir in the south-west, with all increasing stocks by more than 20%. Seven reservoirs or reservoir groups had decreased stocks at the end of October, all by less than 10%. Almost half of the reservoirs we report on were classed as normal for the time of year at the end of October. One reservoir was classed as exceptionally high for time of year, Teesdale group in north-east England. Thirteen reservoirs and reservoir groups (42% of the total) were classed as above normal or notably high. The Pennines Group in north-west England was classed as below normal for the time of year, as was Kielder in the north-east. The Dee system in Wales continues to be impacted by ongoing reservoir maintenance work and was classed as below normal.

At a regional scale, total reservoir storage increased everywhere, with the south-west seeing the biggest increase of 10%. For England as whole, storage increased during October and ended the month at 81%.

6. Forward look

November is likely to experience near average conditions for the time of year. Unsettled, changeable conditions are forecast across the country through mid-November with an increased chance of rain in the east of the country. The unsettled conditions are likely to persist throughout the month, with a chance the north will be wetter than the south.

For the 3 month period between November and January, there is a usual chance of near average conditions for the time of year with the potential for occasional cold spells.

7. Projections for river flows at key sites

By the end of March 2025, flow at almost all the rivers across the country are projected to be normal or higher. The greatest flows are expected in the south-east, and in eastern England, where many rivers are supported by groundwater discharge from porous aquifers.

By the end of September 2025, river flows across England are projected to be normal or higher, with an increased likelihood of above normal or higher flows in eastern and south-east England.

8. Projections for groundwater levels in key aquifers

By the end of March 2025, groundwater levels are projected to be above normal or higher across all of England, as groundwater levels remain higher than expected due to ongoing wet weather.

By the end of September 2025, groundwater levels are projected to be normal across most of England, with a handful of sites in the north and south-east of the country are more likely to see below normal or lower groundwater levels.

Author: National Water Resources Hydrology Team, [email protected]

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.