September rain welcome, but not enough to end water restrictions

Recent rain has not been enough to recover water levels in rivers, reservoirs and groundwater sources across Thames Water’s region after one of the driest spring and summer periods on record.   

The Met Office confirmed summer 2026 was the UK’s hottest on record, while the latest National Drought Group update warned that almost three-quarters of England remains in drought.  

In the Thames Catchment, August rainfall was just 28mm, 43 per cent of the long-term average.  

Groundwater and soil moisture levels remain low, meaning sustained rainfall over weeks or months will be needed before Thames Water can consider lifting the temporary use ban, which has been in place since July. 

Thames Water has stepped up leakage work over the summer as prolonged hot, dry weather can make pipes more prone to bursts. The company is fixing more than 1,000 leaks a week, around 20 per cent above normal, with 18 per cent more people finding and repairing leaks than last year. 

Julie Morton, Head of Water Resources at Thames Water said:  

"While the rainfall we have seen in September is very welcome, it has not been enough to overcome the impact of the prolonged dry weather we've experienced since spring.  

"Across our region, rainfall between March and August was less than half of what we would normally expect, and while some river levels have responded to recent rain, groundwater and soil moisture remain significantly below average. 

"We will need significant and prolonged rainfall over the coming weeks to be able to consider lifting the restrictions that remain in place. 

"We know restrictions are frustrating and we’re grateful to customers for continuing to use water carefully. Every reduction in water use helps protect supplies for customers, communities and the environment." 

Latest water resources position – as of 16th September 2026 

• London reservoir storage was 59%, which is below average for the time of year. Average is 78% 
• Farmoor Reservoir was 75%, which is below average for the time of year. Average is 93% 
• Rainfall so far during September has remained well below the long-term average:
• Thames Valley received 35% of average rainfall 
• London received 41% of average rainfall 
• Soils remain drier than average across the catchment River Flows are below average. 
• Groundwater levels are below normal across the region and notably low in the Thames Valley.