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Hello, my name's Ms. Gilyeat, and I'm going to be your geography teacher for today.
In today's lesson, we are going to be learning about how we can plan river management, which is the final lesson of the river's topic.
Our lesson outcome for today is that you can explain why people have different views about flood protection and evaluate which locations are more likely to receive protection.
Okay, we've got three keywords for today's lesson.
The first one is stakeholder, which is any individual group or organisation that has an interest or concern in a particular geographical area, issue or project.
Slow the flow are methods used to manage flood risk by reducing the speed and volume of water entering rivers in the upper catchment.
And a cost-benefit analysis is a decision-making tool that compares the cost of flood defences with the economic value of what's being protected.
We've got two learning cycles.
So to start off with, we are gonna think about how, or protecting an area from river flooding and what we can actually do, and then we're gonna think about the different stakeholders' view on river management.
So let's get started.
Now, making decisions about river management can be difficult.
Many factors must be considered, including which locations or areas get protected, what methods of river management should be used, and who is involved in the decision-making process.
Okay, so flooding is a growing issue in the UK in particular, and there isn't enough money to protect everywhere that is at risk and nor should it be right that everywhere gets protected.
So making the decisions about where, how and who is involved in this decision-making process is very, very important.
Local governments are responsible for deciding where and how land should be protected from flooding.
They have limited money and resources available so often rely on a cost-benefit analysis to help them make decisions.
Now, a cost-benefit analysis is a decision-making tool that compares the cost of flood defences with the economic value of what's been protected.
Okay, so as I said earlier, the government doesn't have unlimited money to spend on flooding because they've got to think like about other things such as healthcare and education, and therefore the benefits and the positives of protecting areas need to be considered.
Okay, let's check our understanding.
So true or false, a cost-benefit analysis is used in making decisions about river flood management.
That is true.
And can you tell me why? A cost-benefit analysis is a decision-making tool that compares the cost of flood defences with the economic value of what's being protected.
Well done if you got that right.
Now, areas of high economic value are often prioritised for flood protection funding.
Things that will be considered include the value of property, what's there, so infrastructure, thinking about things like train lines, roads, electricity networks, things like that.
How many businesses and the value of the businesses that are in the flood risk area, and also the number of people that live in an area.
Okay, so when considering what land should be protected and how much they should spend on it, they need to think about the value of the land which is at risk of the flooding.
Okay, so we've got two photographs on the slide here, okay? Which area do you think will most likely get funding for flood protection? So think about the economic value of the land.
Okay, so we're absolutely right there that the city will have billions of pounds worth of houses, businesses, infrastructure worth protecting.
So it's much more likely that this photograph is going to get protected from flooding.
Now, hard engineering involves building artificial structures to control rivers and reduce the risk of flooding.
Okay, so you might have already learned about these different methods of hard engineering protection: dams and reservoirs, river straightening, channel dredging, embankments and flood relief channels.
Those are all building physical structures which reduce the flood risk, okay? Now some of the major benefits of these is that they can be very effective, they can reassure communities, they can protect high-value infrastructure, and they tend to have a long lifespan even if they do require quite a bit of maintenance.
So they're quite, yeah, they're structures which work effectively but they cost a lot, okay? And they've got an impact on the land, okay? Some of the major negatives, yes, is that they can be expensive, disrupt habitats, but also they can potentially risk, or increase the risk of flooding downstream.
So these different things have to be considered whether deciding to use them or not.
Okay, so as we have just said, building some of these flood protection strategies can increase the risk of flooding downstream.
Channel straightening, dredging and embankments speed up the flow of the river water and increase the capacity of the water the river channel can hold.
Okay, so they get the water out of an area quickly.
However, that means that further downstream the water is going to get there more quickly and therefore increasing the risk further downstream, okay? So whilst they can protect some areas from flooding, they can shift the flood risk further downstream.
Therefore, this also needs to be considered in the cost-benefit analysis.
Soft engineering river management refers to more sustainable methods of managing rivers and reducing flood risk.
So examples of this is using flood warnings and preparation, so making sure people are aware of a flood event that might occur and what they should do in that event.
Flood plain zoning, so thinking about where's at risk and utilising that land, the best way of using it if an area is going to flood, planting trees and leaky dams. So we'll talk about those in a little bit more detail in a second.
Okay, so major benefits of these is they work with natural processes, they can often improve biodiversity, and they tend to be much cheaper than hard engineering.
However, they can be slower at being effective, okay? There's less control over the outcomes, and they also require maintenance.
Now what's being used more and more are the slow the flow techniques.
Okay, so these techniques are more sustainable methods of use to reduce managing flood risk by reducing the speed and the volume of water entering the rivers in the upper catchment, okay? And what we mean by that is where the rivers are starting.
So the land here is more likely to be on high ground.
You're gonna have many of the sources of the river and many small tributaries, okay? So it's thinking about how we can reduce the amount of water which is going into the main river channel before it actually gets there, okay? These approaches often work with natural processes rather than relying solely on hard engineering.
Okay, now we've already kind of spoken about tree planting.
So when you plant trees, the idea of this is that the leaves and the vegetation collect some of the rainwater that falls down.
And therefore, if they do that, less of that rainwater hits the surface of the earth and therefore less rain water goes to the river channel, okay? So a really effective way of reducing flood risk, okay? Another slow the flow technique is building leaky dams. So if we have a look at my slide on the right there, we've got an example picture of a leaky dam.
So this is building basically little dams in tributaries and small streams, but they're usually made out of wood and they don't just stop all the water flowing them, but they slow the flow of the water that's going through.
Okay, so as it says there, they temporarily hold back water in streams slowing its flow downstream, okay? So they have a small impact on the surrounding land, but the main thing is they're trying to reduce the amount of water from those tributaries getting into the main river channel.
Okay, let's check our understanding.
So looking at the photographs of different river management strategies, which of those are soft and hard engineering strategies? Okay, so tree planting, soft engineering, a dam and reservoir is an example of hard engineering.
And we've got a leaky dam on the right, which is soft engineering.
Well done if you got that right.
Okay, we're onto our first task for the lesson.
So if we look here, we've got a flood risk map of Mytholmroyd which is in West Yorkshire.
So the flood risk map is on the left.
And if you look carefully you can see the key there.
So the darker colour represents areas at higher risk, and the lighter colour represents an area at low risk.
If it's not shaded in at all, there isn't a risk of flooding.
And then on the right we've got a town map of the different things that are in Mytholmroyd, okay? What I would like you to do is, using the two maps, label what is a high risk of flooding in Mytholmroyd.
Okay, so onto the second part of this task, we have got a photograph of Mytholmroyd as well, okay? What I would like you to do is fill in the table.
So first of all, you need to say what the land use is, so that is what the land is being used for.
Is it residential? Is it industrial? Okay, who will be affected by the flood? So will there be residents affected? Will their people be using the roads affected? Will their people be, who potentially own businesses there affected? And do you think the land is of high or low economic value? Okay, so for this task, it'll be wise to use the map alongside the photograph to help you answer the questions.
Okay, let's have a look at the answers for this.
So I've put some of the areas at high flood risk, but there are a couple more if you found those as well.
And then answers for this, so land use, we've got a residential area, there's businesses and there's leisure as well.
Okay, so who will be affected? Residents, business owners and people using the A646 road.
And the land is of high economic value.
There's a lot of people living there, and there's also businesses and infrastructure.
Okay, we're moving on to the second learning cycle, thinking about the stakeholders in river management.
Now the local government are choosing what flood management would be most appropriate for Mytholmroyd.
So we're gonna think about what we should use to try and protect the people and the residents and business owners of Mytholmroyd.
Now we're gonna have a look at two different options.
So option one is using hard engineering by dredging the river and building a flood wall.
So we'll look at some of the costs and the benefits of using option one.
Now the cost of it, it would cost 41 million pounds.
It will disrupt local wildlife, it will create traffic on the A-road, and there's potential flooding downstream in Sowerby Bridge.
The benefits of using option one is it will protect 400 properties, it will reduce insurance costs for businesses, and it will boost community confidence for the people that live there.
Okay, so that is one option that the local government are thinking about for protecting Mytholmroyd.
Option two is using more slow the flow techniques.
So these are strategies by replanting trees and building leaky dams in the upper catchment.
The cost of this is it'll take more time for the techniques to be effective.
You need to wait for some of the trees to grow.
It will be less effective in extreme events, and it may cause conflict with land use changes from the farmers.
The benefits of this strategy, it will improve the biodiversity, it will be low cost, and it will reduce surface runoff and flooding.
So let's check our understanding.
Which of these strategies would be part of the slow the flow technique? A, leaky dams; B, dredging; or C, building a flood wall.
So the answer for that is leaky dams. Well done if you got that right.
Now in river flood management, stakeholders are individuals or groups who are involved in, affected by, or have an interest in managing flood risks and impacts.
Okay? Effective flood management requires input and coordination among many different stakeholders.
The following slides give different stakeholder opinions on the two flood management strategies in Mytholmroyd.
So we're gonna listen to different people's and organisations' opinion on which flood management they think would be better and why.
Okay, so let's just double check that though.
So a stakeholder is someone who makes a decision on river flood management.
Is that true or false? That is false.
And can you tell me why? Stakeholders are individuals or groups who are involved in, affected by, or have an interest in managing flood risks.
They are not always the ones that make the decisions.
Okay, let's listen to some of these then.
So we've got a local resident here, so is a person who is living in a flood-prone area who is directly affected by the flooding.
Let's see what she has to say.
"I would prefer option one for the river to be dredged and a flood wall be built.
I want to feel safe in my own home, and I am worried that the slow the flow technique will take too long to be effective." We've got local and national government responsible for planning emergency response, infrastructure and policy, so for example, the Environmental Agency in the UK.
So they have said, "We have to manage limited budgets while protecting people and infrastructure.
We have to come up with the most cost-effective way of protecting Mytholmroyd.
A flood wall would keep the residents safe, but we are not sure that we can afford it." We've got an environmental organisations, so these work to ensure flood defences are sustainable and protect ecosystems. "We need sustainable, nature-based solutions.
Concrete walls aren't always the answer.
I think option two is the best option as it will prevent flooding, but it will also improve the biodiversity of the area.
I think this is more sustainable in the long term." And we've got businesses as well, so particularly those operating in flood zones, which may suffer economic losses.
So let's see what the business owner of Mytholmroyd has to say.
"Flooding disrupts my business.
Prevention is better than compensation.
I think option one is the best, as I will have more confidence in a period of heavy flooding.
I think this will improve my business but also my mental health.
It will also reduce my insurance costs." Okay, so let's check what we've learned.
Which stakeholders could be more in favour of building a flood wall and dredging the river? Okay, so that's the local resident and the business owner.
Which stakeholder would be more in favour of using a slow the flow technique? And that's the environmental organisation.
Well done if you got those right.
So our final task for this lesson is to make a decision.
Okay, so what I'd like to do is choose which option you think is best for Mytholmroyd and explain why you have chosen that strategy.
I'd like you to include evidence and stakeholder opinions in your answer.
So both of the options are available on the slide there.
So option one is to dredge the river and build a flood wall.
And option two is to plant more trees and build leaky dams. There are two sentence starters on the slide there which can help you structure and start your answer.
Good luck.
Okay, let's have a look at the answer I have got here then.
So this is a model answer.
Obviously you did not have to agree with what I have put.
"I have chosen option one.
The reason I've chosen this option is because I think the residents and businesses of Mytholmroyd deserve highly effective flood management so they can stay safe.
Even though it will be expensive, it will protect 400 properties and make the residents of Mytholmroyd feel reassured.
It'll also reduce the insurance costs for businesses.
The reason I haven't chosen option two to replant trees and build leaky dams is because this could take years for the trees to grow enough to be effective.
It may also cause conflict between the land use owners in the upper catchment." Okay, we've got a summary for today's lesson here.
Areas of high economic value are more likely to receive funding for flood protection.
A cost-benefit analysis is a decision-making tool that compares the cost of flood defences with the economic value of what's being protected.
Building flood protection can increase flood risk downstream.
Slow the flow techniques are increasingly used to prevent flooding.
In river flood management, stakeholders are individuals or groups who are involved in, affected by, or have an interest in managing flood risks and impacts.
And people have a variety of opinions on river management.
Right, that's it for today's lesson.
Fantastic job and I'll see you next time.
Bye.