The summer of 2025 was one of the hottest and driest in recent memory, prompting water companies across England to step up communications campaigns and, in four cases, to introduce Temporary Use Bans. But how much water do these measures actually save, and which customers respond to them? A major UKWIR study, led by HR Wallingford with Artesia as a delivery partner, set out to answer that question using the most extensive dataset yet assembled for this kind of analysis in England. The headline message is that there is no single number. Savings depend heavily on temperature, location, property type and metering status, and that has real consequences for how companies plan for drought.
The research examined water use at three scales: across entire Water Resource Zones, within individual District Meter Areas, and at the level of single households using smart meter data. Looking across these scales allowed the team to see both how regional demand shifts during a drought and how different groups of customers behave, from detached houses with large gardens to flats on a measured bill. The analysis drew on 2025 data alongside reanalysed evidence from the 2022 and 2023 events.
Among the key findings:
- Maximum temperature is the strongest driver of peak demand, but only once it passes a regional threshold, roughly 15°C in the north of England and 20°C in the south.
- Temporary Use Bans have a measurable effect on demand, with the largest savings in bigger, unmeasured households and the smallest in metered flats.
- The evidence for communications campaigns was weaker. Because the campaigns ran at the same time as the bans, it proved difficult to separate the two effects in the data.
Because customer responses vary so widely, the study recommends moving away from a single assumed saving towards factors that reflect temperature, property type and metering status. These conclusions have direct relevance to Drought Plans, deployable output assessments and Water Resources Management Plans as companies prepare for future dry summers.
