The volume of water drawn from Scotland’s rivers and lochs by the agricultural sector surged by more than 500% during periods of water scarcity in recent years, new research has found.

The University of Strathclyde study examined the monthly and annual water use records of more than 80 of the sectors which use most water, including aquaculture, food and drink production, oil refining and paper manufacturing. It identified patterns influencing water use in weather extremes, changes in the economy and industries adapting their practices. 

Extreme weather

Although Scotland is perceived as a water-rich nation, the risk of more varied extreme weather, including wetter winters and drier summers, has increased in recent years, leading to the introduction of the nation’s first formal water restrictions in 2025. Variations of rainfall and other precipitation, according to region and season, mean that several parts of Scotland are more vulnerable in times of water scarcity.

The study, which assessed data from between 2008 and 2018, is the most detailed and comprehensive survey to date of industrial and commercial water use in Scotland, combining records of abstraction and network consumption. It highlights temporary shifts and seasonal changes which are evident in monthly records. 

In one year alone, the three largest using sectors – hydropower, water supply and aquaculture – each consumed more than 200 million cubic metres of water. Changes in the size of other sectors have been reflected by their water use, with declines in manufacturing and increases in services. 

The research has been designed to offer a framework for water demand planning across all sectors, anticipating periods of pressure on water supply and documenting the changing water demand from business and industry. While it focuses specifically on Scotland, it can be adapted for use globally and is particularly useful for environmental agencies and water resource planners.

The paper has been published in the journal Water Resources Management. 

Maria Clemens, a postgraduate research student in Strathclyde’s Department of Economics and the lead author of the paper, said: “We have made a lot of assessments of how much water is needed when there are droughts or floods and, in general, of the impact of climate change.

Anticipate needs 

“We looked for things like seasonality of water use to understand if there are seasons when a sector needs more or less water, or whether event types can be used to anticipate the water sector needs. This could help determine how much water is generally required, so that we can then assess the impact of climate change during droughts or floods.

The study reveals, for the first time, that the largest water users do not consume water in a fixed, predictable way, because their usage shifts constantly in response to weather and water availability.

"While this flexibility is driven by short-term hydroclimatic conditions across all sectors, certain industries such as hydropower, beverages, sewerage and agriculture show that these patterns remain a defining feature of their water demand, even in the long term.”

The research found that agricultural abstraction increases sharply during each prolonged water scarcity period, reaching up to 513% above monthly average levels, while hydropower abstraction rises during floods, peaking at 86% above average. In the beverage sector, it increased by approximately 27%.

Maria Clemens now plans to conduct further research into the UK’s water demand characterisation, including the unusually high domestic water use in Scotland.