Whilst it is very important to transfer water to combat water shortages it is equally important to consider the QUALITY of the water that is being moved. Water quality can be measured in terms of the chemical, physical, and biological content of water. The most common standards used to assess water quality relate to health of ecosystems, safety of human contact and drinking water.
Water in the UK has generally improved in quality over time since the cleaning up of our industrial past. According to the EU, only 27% of our water meets its stringent water quality standards. This means that we have some work to do in ensuring that our open water areas are clean. However, many attempts have been made to keep improving our water.
There are many sources of pollution in the UK that threaten the quality of our water including;
1. Agricultural runoff water, this picks up chemical pesticides and insecticides, nitrates and phosphates (found in fertilisers) and run into our lakes and rivers
2. Historical wastes, water running through old mine workings and old industrial sites can pick up hazardous heavy metals
3. Runoff from roads and motorways including salt used for gritting, oil and heavy metals from car engines and exhausts
4. Sewage waste can end up in our water courses, despite our attempts to clean it
Figure 11 - A stream in the town of Amlwch, Anglesey which is contaminated by acid mine drainage from the former copper mine at nearby Parys Mountain. By Cls14 (Own work) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons
Poor water quality affects the UK because;
• It can potentially poison our water supply, essential for human life
• Eutrophication can occur – this is where fertilisers washed into our rivers and lakes encourage plants and algae to grow, starving other life of oxygen
• Sewage contains bacteria which can spread disease
• Heavy metals and toxins can poison wildlife. These toxins can then end up in people as they work their way up through the food chain in a process of bioaccumulation
• Insect and animal life can be killed unintentionally by pesticides and insecticides, affecting food chains
To combat water pollution, the UK government attempts to do lots of things.
• Educate people – the government having run campaigns for the public to show them the need to use as little water as possible and to not dispose of inappropriate items in our waste water. Not leaving the tap running when brushing your teeth is one way to save water, whilst not disposing of oils or baby wipes is a way to protect our disposal network.
• Laws and legislation – The EU and the UK have very strict laws for our water, which make sure that industries and farms do not pollute it. For example, phosphates contribute to eutrophication. The amount of phosphates allowed in laundry detergent was reduced in2013 and will be reduced for dishwasher products in 2017.
• Treat our water – we have invested huge amounts of money in new treatment plants to clean our water. This is shown on the flow chart below. This can cost a lot of money which creates bigger bills for consumers, but ensures our clean water supply. We have also invested in our pipe and sewer network, to reduce losses of treated water from pipes and to prevent spills of sewage which lead to pollution.
• Improving our water courses – the government have invested in pollution traps downstream of old sources of pollution such as old mine workings, or by using innovative schemes such as the Tees Barrier.