GCSE Geography | Sustainable Water Management (Resource Management - Water 7)

Sustainable water management is all about trying to reach a balance between water consumption (what we use) and water supply (what's available to us), and maintaining this balance long-term so we are not harming the ability of future generations to meet their water needs. To achieve this we need to use water more efficiently and minimise what we waste - currently 1/5 of water in the UK is wasted through leaky pipes!

Groundwater management

Groundwater is the water stored in porous rocks below the Earth's surface (aquifers) - but this source of water is often heavily polluted or over-abstracted to the point that it can't recharge effectively. Groundwater management is all about preventing these two issues.

The Environment Agency monitors water quality in the UK and they can take action against those who pollute groundwater sources to prevent them from discharging water into waterways, which will reduce the risk of future contamination of groundwater. If local aquifers do start to dry up then the amount of permitted pumping can be reduced, enabling time for the water level to recharge, or the groundwater could be topped up with reclaimed water (recycled water) or grey water from sinks, baths, showers and washing machines.

Water conservation

There are lots of ways that we can conserve the amount of water that we use to increase our water security.

Reducing domestic use

• Installing water efficient appliances (e.g. washing machines and dishwashers) and only using them when they are full
• Having showers instead of baths, and using low-flow shower heads
• Installing twin-flush toilet systems which use a small amount of water unless a big flush is needed
• Not leaving taps running, e.g. when brushing teeth or washing fruit and vegetables
• Collecting rainwater in a water butt for watering the garden and washing cars

Investment into water infrastructure

Every day 20% of water is the UK is lost through leaking pipes (such as the burst water main in the image below) - this is around 3.3 billion litres of water, which would meet the needs of a third of the UK population. In February 2024 UK water companies announced that they were going to invest more than £14.4 billion in 2024-25 in infrastructure improvements, including constructing 10 new reservoirs, increasing the capacity of dozens of wastewater treatment works which will increase the capacity to treat sewage, and repairing or replacing more than 2,000 kilometres of pipes. This investment should reduce the amount of water wasted and increase water security in the UK, however it is slightly controversial as the water companies will be increasing customer bills in order to fund these upgrades, despite recording record profits this year.

Improving irrigation efficiency

Irrigation accounts for around 69% of water use around the globe, but it uses water inefficiently, often through a canal network where much of the water is lost through evaporation, when low pressure pipes would transport water much better. It also relies heavily on large sprinkler systems (such as the one pictured below), which don't always spray water where it is most needed, and again lose water due to evaporation. Instead drip irrigation systems would be more effective as they spray water directly onto the roots, where it is needed most. When evaporation occurs it increases the risk of salinisation, when salt crusts build up on the soil, which can harm crops. Irrigation systems are often automatic so can add water to the crops when it is not actually needed, for example after heavy rainfall, and therefore can cause the ground to become waterlogged.

Reducing water pollution

The Environment Agency is in charge of managing water quality across the UK. It regularly monitors river water quality, and when needed it will remove sediment through a filtration process, or add chlorine to purify water. It also has strict regulations on water use, including restrictions on recreational use of water sources, e.g. no power boats on certain reservoirs. It will also impose fines on those who pollute water sources, e.g. Southern Water sewage scandal - in 2021 Southern Water was fined £90m for repeated and deliberately dumping raw sewage. Between 2010 and 2015 it unleashed around 21 billion litres of untreated sewage into local waterways, and is continuing to discharge waste today. By reducing water pollution there will be more water that is safe to use, therefore our water security will increase.

Click here for more information about water pollution

Reusing water

Reclaimed (recycled) water

This is treating and reusing domestic or industrial wastewater to irrigate crops, to use in industrial processes (such as cooling in power stations), to top up rivers and groundwater sources, and for drinking. Reclaimed water has all the impurities removed so it is perfectly safe, and it is much better to re-use the water, rather than discharge it into rivers and seas.

Grey water

This is water that has been used for bathing, showering and washing up, as well as used in washing machines and dishwashers which can be reused to water the garden or flush the toilet. The water contains traces of household cleaning products, toiletries, dirt, hair, food and grease - if used within a day these provide valuable fertilisers for watering plants, but if left to sit in a storage tank this water quickly becomes stagnant and high levels of bacteria will build up, so therefore greywater systems are not widely used, although they are more common in LICs, for example, 70% of water used for irrigation in Jordan comes from grey water.