This July the Environment Agency reported that UK river flow rates reached their lowest point in two decades.
The UK is now in a similar situation to its European counterparts, as places like Spain suffer some of the worst dry spells in recent memory.
Each year, data is collected in July for indications of drought severity, where everything from groundwater levels (the amount of water stored underground), reservoir levels, (the amount of water held by a reservoir) and flow rates (the volume of river water passing a specific point over a fixed time) are measured.
The record lows of 2022 spark concerns that the UK is entering another extended drought
A 2022 analysis by the Wildlife and Countryside Link showed that 88% of rivers had reduced flow rate, 67% of sites had low groundwater levels and the average reservoir held only 64% of full capacity.
Since 2002 there have been three periods of drought. But, the record lows of 2022 spark concerns that the UK is entering another extended drought, with indicators expected to get worse in 2023.
Extreme weather currently faced across the world is at least in large part a consequence of human induced climate change
David King of the Climate Crisis Advisory Group
Future droughts are expected to occur more frequently, and this, as David King of the Climate Crisis Advisory Group explains, is partially caused by human activity: "Extreme weather currently faced across the world is at least in large part a consequence of human induced climate change".
Drought can be devastating for many reasons. Firstly, it impacts the wildlife that relies on waterways. Grasslands dry up, compromising the survival of terrestrial ecosystems and riverbank vegetation depletes, reducing shade. Not only this, but human pollutants and nutrients released into rivers become concentrated due to reduced flow.
All of these effects are harmful in themselves, but serve to create a reactionary cycle of natural decay too. For instance, stagnant rivers with little gas exchange result in low concentrations of dissolved oxygen and, as a result, fish and aquatic insects struggle to survive.
Greater nutrient availability helps algal blooms to grow and outcompete aquatic plants, whilst low flow rates mean harmful blue green algal blooms have more time to grow and reproduce before being swept out to sea.