For Water Saving Week, Waterwise caught up with WildFish to explore a question we don’t often ask when thinking about water use: what does our demand for water mean for fish in the UK?
As more water is taken from rivers to meet growing demand, the impact is being felt across the ecosystems that depend on them. In this Q&A, we put some key questions to WildFish:
Understanding WildFish and their work
Waterwise: Can you tell us about WildFish and what you’re working to protect?
Wild fish populations are collapsing as their habitats are destroyed faster than ever before. At WildFish, we exist to reverse this decline and protect wild fish and the waters they call home. Our goal is to safeguard freshwater and coastal habitats for sustainable fish populations and improved biodiversity. We do this by inspiring, informing and mobilising everyone who can take action – from individuals and communities to policymakers and businesses.
How much pressure are our rivers under?
Waterwise: When we turn on the tap, what’s the link to our rivers?
Increasingly, rivers face the threat of over abstraction – the process of taking more water out of a river system than can be naturally replenished. We currently abstract 14 billion litres of water per day from rivers and groundwater in England and Wales. That’s equivalent to 5,600 Olympic swimming pools every single day. Worse still, the government predicts that there will be a shortfall of 5 billion litres per day by 2050 in England alone.
Rivers and streams that were once teeming with life are now labelled as “water stressed”. Species like the Atlantic salmon, once plentiful, are now endangered in the UK. In some smaller rivers they’ve disappeared completely. This pattern will continue unless we take urgent action to address water stress.
The demands of public water supply, industrial use (including agriculture) and the impact of climate change mean our rivers do not have sufficient water to dilute pollution or support thriving fish populations. The impact is that the insects that live in these waters and the fish that depend on them are often severely depleted in terms of both their diversity and abundance.
What happens to rivers when flows drop?
Waterwise: What changes in a river ecosystem when water levels fall or flows are reduced?
- Stop migrations: lower volumes of water mean that fish are less able to migrate up and down rivers to complete their life cycles.
- Reduced water quality: pollutants in the water become more concentrated because of the lack of dilution.
- Smothered spawning gravels: increased sedimentation clogs up river gravels because there is not enough flow to move them.
- Less shelter and food: reduced water levels mean less wetted habitat area, limiting food availability and refuge for wild fish.
- Warmer water and lower oxygen: temperatures rise and oxygen levels fall, which can lead to mass fish mortalities.
Where is the impact being seen most clearly?
Waterwise: Can you share a real example of where the over consumption of water is already having a visible impact on rivers and fish populations?
Nowhere is this pressure more apparent than on the rivers Test and Itchen in Southern England. These chalk streams are globally rare ecosystems, only 200 remain in the world, and 85% of them are in England. Despite their rarity and environmental significance, in times of water stress water companies rely on them to meet public demand, abstracting water which puts severe pressure on wild fish populations. Atlantic salmon, which depend on cold, clean, fast flowing water, have suffered dramatic declines. In some chalk streams, they have vanished entirely.
That’s why we’re campaigning for better protection of chalk streams and calling for all of them to be designated as Special Areas of Conservation to safeguard these rare ecosystems and the unique populations of salmon that depend on them.
What can actually make a difference?
Waterwise: With this scale of challenge, what are the most practical actions households or businesses can take to help reduce pressure on rivers?
On average, a person in the UK uses 146 litres of water per day. By comparison, residents in Denmark use less than 101 litres per day. Simple actions to reduce water use at home can have a positive impact on rivers by lowering our overall demand for water.
For practical tips on saving water at home, work and school, we recommend visiting Waterwise’s “How to save water” guides.
Why this matters
Waterwise: Why is it important for people to understand the connection between their daily water use and the health of rivers and fish?
Rivers are a shared responsibility. When we draw water from them, we’re not just reducing the quantity, we’re altering an entire system that is fundamental to life on Earth.
Fish have evolved around the natural rhythms of river flow. Salmon, for example, time their migration and spawning around seasonal flows. Reducing the flow at the wrong time can cause fish to become stranded, expose their spawning beds to air and prevent adults from reaching spawning grounds.
Our water use at home is directly connected to the health of our local rivers and the fish that depend on them. The more informed we are, the better placed we can be to make good decisions about how water is used and protected -and to hold decision makers accountable for safeguarding these vital ecosystems.
Want to go further this Water Saving Week?
Explore more practical ways to save water and reduce pressure on our rivers, and read our latest blog with The Rivers Trust: The Hidden Connection Between Your Water Use and Wildlife.
