Lesson video

Hello, geographers.

My name is Mrs. Griffiths, and today's lesson is all about water resources in the UK.

So we're gonna be focusing on the changing demand for water resources between different regions and in local places, and thinking about how we can meet that demand.

So what the opportunities and challenges are in terms of meeting our growing demand for water.

So shall we make a start? And our outcome for today is I can explain how changing demand for water in the UK creates opportunities and challenges.

That's what I hope you can say by the end of today's lesson.

We have some keywords today.

So there's water transfer, which is the movement of water through pipes or via canals or rivers from areas of water surplus to areas of water deficit.

Water stress is when the demand for water exceeds the available amount during a certain period or when poor quality restricts its use.

Water quality is a measure used to assess the suitability of water for drinking and for supporting river ecosystems. So look out for those keywords in what we're gonna be having a look at today.

Now, our lesson, as I say, the title is "Water resources in the UK" and it breaks down into two key questions which we're going to answer.

How is the UK's demand for water changing and how can we manage water pollution? So let's make a start on that first question, how is the UK's demand for water changing? Now, what does this map show? I've taken a screen grab here from a GIS system.

So a Geographical Information System, sorry, and it's the geography visualizer.

Now, the map appears to be called, "Where do we Live?" And if you take a closer look, this GIS features an interactive map of the UK's population.

The population is shown on the map of the UK as if the country were divided into equal-sized hexagons.

It shows where more people live, but there are no familiar city boundaries.

Let's take a closer look.

Now, despite the unfamiliar use of hexagons or they're called hexbins here, it's easy to see where the UK's largest settlements are.

So we can easily spot London and Birmingham and Manchester even without those labels.

And population density you can see is mapped using colour, the darker colour for the denser populations within each of those hexagons.

Now, on this map, it's slightly different.

What I've done, I've added an extra layer, so let's come back to that in a second.

So mapping population density gives us an understanding of whether demand for water's greatest for domestic consumers, industry, and services.

Here, England's population density by region has been added as a sort of semi-transparent layer on top of that hexagonal pattern.

So it allows us to generalise by region.

We can see the darker the colour of the region, the more, the higher the population density overall.

But the hexagons, let us see the detail within that and where those big settlements are.

We can see that there's clearly a high population density and perhaps that's creating demand issues within the Southeast.

But let's for once, let's just have a focus on the East Midlands region.

So if we zoom into the East Midlands region between Manchester and Sheffield, the Peak District, you might have heard of that, it's a national park, is part of an area of low population density.

And I've added a ring to show that.

Southwest of this are the cities of Derby, Nottingham, and Leicester.

And then within my second ring, you can see we have Derby, and then east of that is Nottingham, and south of that is Leicester.

So we can see those are areas of high population density much higher than the Peak District, clearly.

If I change the layer and I just changed the layer to population growth.

Looking at population growth over a 10-year period, the darker colour shows growth was high in Leicester and the surrounding boroughs.

So we got an idea of density and also population growth.

And that's gonna be relevant to demand for water, isn't it? Over a 10-year period, the population of Leicester increased by 10.

5%.

And neighbouring areas increase by 12%.

However, the high peak within that Peak District national park area is a sparsely populated area, and it saw a 0% increase between 2011 and 2021.

So population growth in areas of high population density are likely to create challenges for the supply of resources such as water.

Different map here using the geography visualizer.

This map is called "UK Climate", and I picked a layer which is specifically average rainfall.

So average total rainfall, where does it rain most when you look at that map? Well, I'm sure you spotted looking at that colour key that the blue and that specifically the darkest blue areas are the wettest areas because it's a choropleth map that shows that the UK's water resources are plentiful on the west coast of Scotland and the associated highlands, in Cumbria in England, and in the west of Wales.

And there's a comment there.

It rains most over high land over the UK's hills and mountains.

I'm sure you knew that.

This is, of course, relief rainfall.

Now, if we zoom back into the East Midlands region and we have a look at annual rainfall, Kinder Scout is the highest peak in the Peak District with a very different annual rainfall total to the city of Leicester.

And we've got many grass there to compare the two.

Kinder Scout has a total rainfall of 1,536 millimetres per year compared to Leicester, which has a total annual rainfall of 655.

5 millimetres per year.

Very different.

So the High Peak area drained by the River Derwent and its tributaries is an area of water surplus.

Leicester is an area of population growth and industry, and might be termed an area of water deficit.

Sticking with my GIS package here, I've got another screen grab showing.

We can, of course, measure the distance between places here and I've measured the distance between Kinder Scout.

Remember that's the highest peak in the Peak District and the centre of the city of Leicester.

The straight line distance from Kinder Scout to the city of Leicester is almost 100 kilometres.

And a water transfer scheme enables the populations of Darby, Nottingham, and Leicester to benefit from water resources from the Upper Derwent valley.

There are three reservoirs and a 45-kilometer long aqueduct along with an extensive local network of pipes that make this transfer possible.

Here, we have satellite imagery of Howden, Derwent, and Ladybower reservoirs.

Remember, I said there were three reservoirs, and you can see when they were constructed, 1912, 1916, and then 1945.

If by the magic of GIS, I transform that into a view of the relief of the land, we can really see that river network, can't we? And how the dams have made really good use of that river network to create three reservoirs.

Here, I've added the three dams, and we can see a photograph of Ladybower Reservoir Dam.

Carsington Reservoir created more storage.

So this is another reservoir that was created in 1992.

It's a fourth reservoir that was created further south to store additional volume that might be pumped up from the River Derwent at a time of surplus to be stored.

And in 2022, water company, Severn Trent announced a plan to expand the three reservoirs in the Upper Derwent Valley or to build another reservoir nearby.

This plan aimed to double water storage to address dry summers and a growing population.

So perhaps hinting at the impact of climate change on this catchment, but raise concerns about environmental damage including the loss of ancient woodland.

Check for you here.

True or false, due to high rainfall in the UK, all regions are able to meet their demands for water.

Is that true or false? And I want you to explain why.

So pause the video, and then restart it when you have an answer.

And if you said false, what was your explanation? Why is that a false statement.

We had, despite high rainfall overall in the UK, water demand can still exceed supply in some regions, especially during dry summers or in areas with high population density.

Water availability varies across the country.

Water transfer schemes help to address this.

So clearly, geography matters, but water transfer schemes can come to the rescue.

Oh, this is an interesting map, isn't it? Here we've got a map of water transfers across England and Wales.

The East Midlands clearly is not the only region of England with a water transfer scheme.

And clearly, you can see there that's the transfer we've been focusing in on.

There's a real need for water transfer to maintain supplies in much of the east and the south of England.

In the west, water transfers have been created to transfer water resources from rural uplands to key centres of population, including there we can see Greater Manchester.

Now, population growth.

I've mentioned this before, haven't I? But population growth is not the only cause of water stress when demand exceeds supply.

Something called the water risk index considers factors that affect quantity and quality of water.

Factors affecting quantity include unsustainable use of groundwater, competition for water resources, and drought linked to likely climate change.

The water risk score is higher for areas with darker shading on this map.

Now, greater London and the southeast of England are at greatest risk of water insecurity according to the World Resources Institute.

Population is high with a drier climate on average.

Absolutely right.

However, the pattern of population growth is more widespread across England.

And you and I know that from our work we've done on looking into the East Midlands.

So perhaps, there's an issue of water stress that is, is wider than just the southeast and greater London.

Now, the UK's environment agency maps areas of England affected by serious water stress in 2021.

These areas are the way the map is divided up is it's water resource zones primarily linked to water companies.

Only 8 of the 23 water resource zones were rated not serious for water stress.

So we've got that big red area covering much of England.

The calculation of serious water stress takes into account this is what the environment agency took into account, current and likely future household demand, current and likely future rainfall available.

Water companies in areas which are under serious water stress are able to charge all customers for the volume of water used.

So volume has to be measured by a water metre on each property.

So that's a change that's taken place as a result of this assessment of water stress.

Water stress applies to both the natural environment and public water supplies, because both will be affected by climate change.

So we're not just thinking about people, we're thinking about the needs of our natural environment as well.

Check for you here.

What are the main causes of water stress in the UK? Have a read of those.

Pause the video, and restart it when you know what the answer is.

Or answers.

And if you said, well, A, B, and D are all causes of water stress in the UK, you'd be absolutely right.

Uneven distribution of rainfall, yeah.

Lack of competition for water resources, not true.

Population growth increasing the demand, yep.

Increased drought as a result of climate change.

Practise task for you here.

Using the data below and your own knowledge, outline where demand for water resources may create a challenge.

And you've got two bar graphs to have a look out there.

Usual resident population and population change.

Secondly, I'd like to explain why there is a need for water transfer within the UK.

So it's time to grab a pen, pause the video, and have a good go at those tasks.

The second one being perhaps a little trickier.

Restart it when you want to check your answers.

Okay, so how do we get on? Our first question was using those bar graphs and our own knowledge to outline where demand for water resources may create a challenge.

Regions such as London and the Southeast have a large and growing population, which increases pressure on water supply.

The east of England has a growing population also.

These regions receive less rainfall than other parts of the UK, leading to an imbalance between supply and demand.

This combination of high demand and low natural water availability makes them particularly vulnerable to water stress, especially during dry periods.

So that's the challenge.

That said, regions such as the East Midlands and Southwest also have growing populations, creating specific local areas, local pockets, where demand creates water stress.

What I like about that answer is it's not just touching on one region, it's touching on a number of different regions and talking about the challenges they're in.

If you had something like that, well done.

Question two was explain why there's a need for water transfer within the UK.

Now, your answer may include something like this.

Water and rainfall is not evenly distributed across the country.

Some areas like the north and west, receive high levels of rainfall and often have a surplus of water.

In contrast, areas in the south and east such as London and the Southeast, have higher population densities and lower rainfall, leading to greater water demand and potential shortages.

Water transfer schemes help move water from areas of surplus to areas of deficit, ensuring a more reliable and balanced water supply across the country, especially during dry periods or droughts.

Now, what I like about that answer is it uses some key terminology.

So we've got our buzzwords like surplus and deficit, and we've also got the idea that actually there are particular periods which are problematic in terms of time periods or drought periods.

Well done if you had something like that.

Right, second half our lesson, we're gonna have a look at this second question, how can we manage water pollution? What are the key causes of water pollution in the UK? Have a think.

We had agricultural runoff from crops and livestock, industrial use and discharges, heavy rain and sewer discharges.

Let's have a look at those in turn then.

Agricultural runoff.

Farming is a diffuse source of pollution, which means pollutants don't enter our waterways at a single point.

Rather, agricultural runoff enters rivers across a landscape.

So not a single point.

In 2018, the government created new farming rules for water to reduce pollution.

For example, from livestock.

So the new rule said that livestock must be kept 50 metres away from sources of water.

That makes sense, doesn't it? Manure.

So that must be effectively stored to avoid spills and contamination.

Fertilisers and pesticides.

So the new rules said that chemical use should be more limited and must be away from rivers, springs, and boreholes to avoid that contamination.

Ploughing must maintain soil structure and prevent erosion.

So some key ideas about how to protect our water resources.

In the UK, the regulation of what industries can and can't discharge into the environment has changed over time.

So it's become more stringent over time.

More recent, UK and EU laws designed to limit pollution from manufacturing or chemical industries has helped to clean up British waterways.

That's absolutely true.

So here's an example of a label that you might have seen on some solutions perhaps you have at home, or that you've used in the science lab.

And this label indicates that a substance is hazardous to aquatic life or other species limiting how and where it can be disposed after its use.

However, so despite this legislation, there are new challenges to the quality of our water and our rivers.

Microplastics and so-called forever chemicals are emerging threats that water scientists want more research into to protect our waterways.

So we can't rest on our laurels with this one.

Check for you here.

What are the main causes of water pollution in the UK? Pause the video, and then restart it when you want to check your answers.

And if you said A, C, and D, you'd be absolutely right.

Well remembered.

I haven't actually talked about D yet, have I? Let's have a think about that.

First question, do you know how sewage is treated in the UK? Hmm, well, it's a multi-stage process.

So let's think about wastewater treatment, wastewater being another word for sewage.

First stage in the process is the screening.

So large screens remove large debris such as wet wipes, sanitary items, and rags from the wastewater when it first arrives at a water treatment plant.

Settlement tanks are involved in the second stage.

So this is where solids sink to the bottom to form sludge, often used to create renewable energy.

And here's an example of a large settlement tanks in a treatment plant.

So you can picture it.

Aeration then takes place.

This enables bacteria to break down any remaining organic matter in water.

And this is followed by more settlement tanks, creating further sludge, and clean water which flows off the top.

Finally, water's passed through a bed of sand, which is that final filtration stage.

So a multi-stage process.

So here, we have an example of domestic waste.

Okay, you flush the toilet, what happens next? That water flows into the sewage network, it goes onto the treatment plant through that multi-stage process.

And eventually, will be discharged into a river or water course.

Once thoroughly treated, then water can be returned to waterways, replacing volume abstracted from rivers upstream for us to drink.

So that water goes back into the water system.

Question, how does intense rainfall affect water quality? Does intense rainfall disrupt this process that we have set up? Well, if you add heavy rainfall at the same time as we continue to use water in the home, what happens is that combined drains and sewers may become overwhelmed.

And as a result, raw sewage is released into waterways to prevent large scale flooding.

Let's have a look at that.

So heavy rainfall can overwhelm a treatment plant if it exceeds its capacity as water from road drains flows into the sewer system.

Combined sewer overflows avoid the flooding of homes and linked pollution.

So this is allowed currently, but there is concern that the release of raw sewage into our waterways is too frequent.

And think about the way the climate is changing.

There are some big problems here, aren't there? Question here, I thought the UK's rivers were supposed to be the cleanest ever? Well, since the industrial revolution? Well, environmental laws have been effective in reducing wastewater pollution, including EU legislation in the mid-1990s.

But other issues such as combined sewer overflows, like I was talking about, combined with intense rainfall, along with emerging pollutants like microplastics and the effect of intensifying agriculture in some parts of the country mean greater monitoring is needed, if we want to look after our water quality, which of course, we do.

Check for you here.

True or false, our waste water is treated and sent to our taps to drink.

Is that true or false, and why? And if you said false, what was your explanation? Ours was few water systems link wastewater treatment plants to the supply system, with treated water going into covered reservoirs first before the clean water network.

So it's kind of a very few examples of that within the UK.

Most systems release treated wastewater into rivers from where it has abstracted downstream later on.

Okay, so that's why it is false.

Well done if you had that.

Question here, who's gonna do something about the release of raw sewage into our waterways? It's disgusting! Well, that is kind of a really strong reaction, isn't it? That lots of us are having at the moment.

The Environment Agency, part of the government, manages water quality via monitoring, so they sample rivers.

Regulation, so creating new laws which restrict the use of water and what you can discharge into rivers and enforcing those laws, for example, via fines.

In 2022, 6,000 sewage spills into rivers occurred outside of periods of heavy rain.

So I was talking about that heavy rain problem, but these are actually something worse and different, illegal dry spills.

Meaning, more work for government workers monitoring water pollution.

Clearly, something needs to be done.

Check for you here.

Which of the following helps us to manage water pollution? Pause the video now, and restart when you have an answer.

And if you said, well, it's the first three, monitoring rivers, enforcement, and improved infrastructure and wastewater treatment, you're absolutely right.

Well done.

First task for you here, then time to grab a pen.

Can you complete the table describing these three causes of water pollution in the UK? So we have agricultural runoff, industrial use and discharges, heavy rain and sewer discharges.

So that's your first task.

I have one more for you.

Secondly, what can be done to improve the UK's water quality? Use this newspaper article and your own knowledge.

So you're going to need to read that newspaper article carefully, use that and your own knowledge that you're bringing to this question in your answer.

That is my hint, right? I suggest you pause the video now, and make a start on those two tasks.

Restart it when you want to check what you have written.

How did you get on? Well, our first task was asking you to complete this table.

So we need to look at these three causes and think about how they cause pollution.

So agricultural runoff, we had rain washes fertilisers, pesticides and animal waste from farmland into rivers and streams, leading to nutrient pollution, which harms aquatic life.

Industrial use and discharges.

Well, that's all about factories and industrial sites, which may release pollutants such as heavy metals, oils, and chemicals into nearby rivers and lakes, damaging ecosystems and water quality.

And then lastly, we have the idea that heavy rain and sewer discharges create pollution, because during heavy rain or system failures, untreated, or partially-treated, sewage can overflow into water bodies.

So it's actually released by those combined sewer overflows.

So those water courses become polluted and they might be polluted with harmful bacteria, chemicals, and solid waste detritus.

Well done if you've written something like that.

Secondly, what could be done to improve the UK's water quality? This is a big concern for lots of people, isn't it? Your answer might include something like this.

Monitoring is important, such as the regular sampling of rivers to check for pollutants, as this helps to spot problems early.

The government can introduce regulations, like new laws to control what can be enforced into rivers.

Sorry, what can be discharged into rivers from farms, factories, and sewage systems. Enforcement is also key, for example, fines or criminal charges for companies that break pollution laws, making sure that they take responsibility.

Wastewater infrastructure must be upgraded to ensure it can cope with the UK's increasingly intense rainfall and ensure that sewage is properly treated before it's released into rivers and seas.

That was a tricky one, wasn't it? You had to suggest what could be done.

Well done if you've come up with maybe two possible solutions.

Okay, so in summary, what have we been looking at today? Well, changing demand and provision of water in the UK creates opportunities and challenges.

Demand for water is changing due to population growth, and there are regional issues matching supply to demand.

This means that there's a need for water transfers within the UK to maintain supplies.

65% of water resource zones within England were rated as having serious water stress in 2021.

So this is something that you haven't heard the last of, I think.

There are various causes of water pollution including agricultural runoff, industrial discharges, and sewage spills.

Pollution management such as monitoring and legislation such as lawmaking is needed to maintain water quality and protect the environment.

Thank you for joining in with this lesson today.

I think there was some kind of tricky tasks there and a lot to take on board, and also we did that whole journey through the use of GIS.

So perhaps, that's inspired you to go and experiment with that as well.

I look forward to seeing you again soon.

And farewell.