Research and analysis

North West water situation: October 2024 summary

Updated 13 November 2024

Applies to England

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

1. Rainfall

October saw varied rainfall across north-west England, with over 75% of the month’s rainfall occurring between 14 and 27 October. High rainfall totals were recorded at Ulpha and Ennerdale rain gauges, with both sites recording in excess of 70mm of rainfall on 27 October.

Following the rainfall during the latter half of October, rainfall for north-west England was classed as normal, at 101% of the long term average (LTA). Cumbria and Lancashire was also classed as normal, at 106% of the LTA. Greater Manchester, Merseyside and Cheshire (GMC) observed 100% of the LTA, also classed as normal.

All hydrological areas in October were classed as normal, with the highest rainfall (in terms of the LTA) being the Cheshire Rivers Group hydrological area which received 119% of the LTA, and the lowest being the Derwent hydrological area which received 86% of the LTA. There were no clear spatial trends in rainfall for October.

During the 3-month cumulative rainfall period ending in October, coastal hydrological areas were wetter than predominantly inland hydrological areas – namely the Eden, the Ribble, and the Mersey and Irwell hydrological areas which were classed as normal. The Esk (Cumbria) and the Cheshire Rivers Group hydrological areas in particular were classed as notably high. The remaining hydrological areas were all classed as above normal.

The 6-month cumulative rainfall period ending in October, sees a similar trend with the Ribble, and the Mersey and Irwell hydrological areas still being classed as normal. Meanwhile, the Esk (Cumbria), the Kent, and the Cheshire Rivers Group hydrological areas were classed as notably high, reflecting the predominant path taken by low pressure systems over the last 6 months. The remaining hydrological areas were all classed as above normal.

The 12-month cumulative rainfall totals reflect how wet the previous year has been, with all hydrological areas in north-west England being classed as exceptionally high, despite the drier weather over the last few months.

The 12-month period ending in October was also the either the first, second, or third wettest since 1871 (153 years) for all hydrological areas, except for the Esk (Dumfries) hydrological area. Notably for:

• GMC, at 1245mm, breaking the 152-year-old record of 1203mm in 1872
• Esk (Cumbria) hydrological area, at 2423mm, breaking the previous record of 2315mm in 2016 by over 100mm
• Cheshire Rivers Group hydrological area, at 1135mm, breaking the 152-year-old record of 1090mm in 1872
• Kent hydrological area, at 2431mm, breaking the previous record of 2361mm in 2016

2. Soil moisture deficit and recharge

Rainfall recorded during the latter half of October resulted in a reduction in the spatial variability of soil moisture deficits (SMD) across north-west England at the start of November, SMD levels ranged from 0mm to 4mm. This is lower than expected for the time of year for the whole of north-west England, particularly for central Lancashire, Greater Manchester, Merseyside, and Cheshire.

3. River flows

Please note that monthly mean flows recorded at the River Bollin at Bollington Mill gauging station have not been included in this report due to data quality concerns.

The spatial distribution of September’s rainfall continued to be reflected during October, with the highest mean river flows (in terms of percentage of the LTA) being recorded in western areas of central Lancashire and GMC. This was due to rainfall falling in catchments that were saturated during September, maintaining the river levels high in these catchments.

With the exception of the Mersey catchment at Ashton Weir which changed from normal to above normal, and the Derwent catchment at Seaton Mill which changed from normal to below normal, all sites remained at the same classification as they did in September. The latter was caused by the below average rainfall received in the Derwent hydrological area in both September and October.

River flows were highest (in terms of percentage of the LTA) in the Weaver catchment at Ashbrook (348% of the LTA, classed as exceptionally high), and lowest in the Derwent catchment at Seaton Mill (59% of the LTA, classed as below normal).

For the other 22 indicator sites reported this month:

• 17 sites were classed as normal
• 5 sites were classed as above normal

Heavy rainfall recorded across north-west England during the latter half of October resulted in some notable peaks in daily mean flow recorded during October.

Daily mean flows above Q1 (this is where mean flow has been exceeded only 1% of the time during the lifespan of the gauging station) were recorded on either the 16 or 17 October at:

• Caton gauging station on the River Lune
• Duddon Hall gauging station on the River Duddon
• Kirkby Stephen gauging station on the River Eden
• Hodder Place gauging station on the River Hodder
• Lunes Bridge gauging station on the River Lune
• Samlesbury gauging station on the River Ribble
• Sheepmount gauging station on the River Eden

Also on 27 October at:

• Cropple Howe gauging station on the River Esk

In addition, daily mean flows above Q0.1 (where mean flow has been exceeded only 0.1% of the time) were recorded on 16 either the or 17 October at:

• Croston gauging station on the River Yarrow
• Kirby gauging station on the River Alt
• St Michaels gauging station on the River Wyre
• Ashbrook gauging station on the River Weaver
• Causey Bridges gauging station on Sankey Brook

4. Groundwater levels   

Groundwater levels across north-west England at the end of October were classed between normal and exceptionally high. Groundwater levels decreased at:

• Bruntwood Hall, from exceptionally high to above normal
• Primrose Hill, from above normal to normal
• Skirwith, from exceptionally high to notably high

All other groundwater indicator sites remained at the same classification at:

• Brown Bank Lay-By, classed as notably high
• Furness Abbey, classed as exceptionally high
• Great Musgrave, classed as normal
• Lea Lane, classed as normal
• Priors Heyes, classed as exceptionally high
• Richmond Park, classed as exceptionally high
• Victoria Road, classed as normal

Please note, levels at Priors Heyes remain high compared to historic levels because the aquifer is recovering from the effects of historically high abstractions.

5. Reservoir storage

Total reservoir storage for north-west England increased from 75% from the end of September to 76% at the end of October. This is higher than the average of 75% at this time of the year, but lower than this time last year when total reservoir storage was 83%.

At the end of October, reservoir storage (in terms of percentage) was highest at Crummock Water, and Ennerdale Water, which were both at 100% full. This was followed by Lake Vyrnwy which was 87% full. Storage was lowest at Haweswater (68%) due to lower than average rainfall in the area in September (71% of the LTA) and October (96% of the LTA) recorded at Burnbanks rain gauge, and due to increased abstraction for public water supply.

The combined storage at Haweswater and Thirlmere was at 71%. This is higher than the average of 68% at this time of year, but lower than this time last year when storage was 79%.

Reservoirs kept low for maintenance works include part of the:

• Longdendale system – Audenshaw No.1, and Torside
• Rivington system – Anglezarke, High Bullough, and Yarrow
• Worthington system – Arley, and Worthington
• Bolton supply system – Dingle
• Poaka Beck system – Harlock
• Piethorne Valley system – Norman Hill, Ogden (Milnrow), Kitcliffe, Piethorne, and Rooden
• Ogden (Barley) system – Ogden Lower, and Ogden Upper
• Barnacre Group system – Barnacre North
• Longridge system – Alston No.1, Alston No.2, and Spade Mill No.2
• Dee (Celyn and Brenig) system – Llyn Celyn
• Cowpe system – Cragg
• Dubbs system – Dubbs
• Belmont system – Belmont
• Worsthorne system – Swinden No 1.
• Watergrove system – Watergrove

Author: Cumbria and Lancashire Hydrology Team, hydrology.CMBLNC@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 herein.