Pick a Number to Reveal the Pick a Number to Reveal the Picture!Picture!

1 2 34 5

Continue..

Info Back

Insert image of Cadair Idris or similar steeply sloped landform

BackInfo

GRANITE ROCK

CHALK ROCK

VInsert image of Chalk Rock

Insert image of Granite Rock

Back

Info

Insert image of woodland

Insert image of heather moorland

V

Back

Info

Insert OS map that showsarea with many streams

Insert OS map that shows area with one river and few or no

streams

V

Back

InfoInsert image of cumulonimbus cloud(s)

Insert image of nimbostratus cloud(s)

V

STEEP STEEP SLOPESSLOPES

• A drainage basin with steep slopes will result in any A drainage basin with steep slopes will result in any precipitation rapidly entering the river channelprecipitation rapidly entering the river channel

• This will result in the peak flow (discharge) of the river being This will result in the peak flow (discharge) of the river being high and responsive in that it will reach peak discharge high and responsive in that it will reach peak discharge quickly and then fall away quickly once the rainfall event has quickly and then fall away quickly once the rainfall event has endedended

Back to Picture Back to Picture Board

The steep slopes found The steep slopes found on (e.g. Cadair Idris) on (e.g. Cadair Idris) results in a rapid results in a rapid transfer of water into transfer of water into the Nant Cadair the Nant Cadair streamstream

Insert image of Cadair Idris or similar steeply sloped landform

GEOLOGYGEOLOGY

The chalk (above) is The chalk (above) is permeable and as a result permeable and as a result water is absorbed by the water is absorbed by the rock rather than allowing it rock rather than allowing it to flow overland into the to flow overland into the river channelriver channel Back to Picture BoardBack to Picture

The granite (below) is The granite (below) is impermeable and as a impermeable and as a result drainage basins with result drainage basins with rocks of this type will rocks of this type will promote rapid runoff and promote rapid runoff and could lead to floodingcould lead to floodingInsert image of Chalk

Rock

Insert image of Granite Rock

VegetationVegetation• Vegetation can Vegetation can

influence river influence river floodingflooding

• If a drainage basin has If a drainage basin has woodland like in the woodland like in the top picture, then more top picture, then more of the rainfall will be of the rainfall will be intercepted and intercepted and subsequently lost due subsequently lost due to evavoptranspirationto evavoptranspiration

• If little vegetation is If little vegetation is present, more water present, more water will enter the river and will enter the river and promote a higher promote a higher peak dischargepeak discharge

Back to Picture BoardBack to Picture

Insert image of woodland

Insert image of heather moorland

• Some areas have a high Some areas have a high number of streams draining the number of streams draining the land, whereas other have very land, whereas other have very few.few.

• These differences in drainage These differences in drainage density will result in differences density will result in differences in the speed in which water is in the speed in which water is transferred and therefore the transferred and therefore the potential flood riskpotential flood risk

Back to Picture BoardBack to Picture

• The map of (e.g. Snowdonia) The map of (e.g. Snowdonia) above has many streams and above has many streams and a high drainage density (& a high drainage density (& steeper slopes)steeper slopes)

• The (e.g. River Meon) is the The (e.g. River Meon) is the only river on the bottom map- only river on the bottom map- it has a low drainage densityit has a low drainage density

Drainage Drainage DensityDensity

Insert OS map that showsarea with many streams

Insert OS map that shows area with one river and few or no

streams

Cloud types Cloud types and rainfalland rainfall

Back to Picture BoardBack to Picture

• The cumulonimbus The cumulonimbus cloud at the top will cloud at the top will produce intense produce intense torrential rain which torrential rain which has the potential to has the potential to produce serious produce serious floodingflooding

• The Nimbostratus The Nimbostratus clouds on the right clouds on the right are normally are normally associated with light associated with light drizzle drizzle

Insert image of cumulonimbus cloud(s)

Insert image of nimbostratus cloud(s)

Insert image of dense urban environment

Urbanisation – Human Urbanisation – Human Influence on floodingInfluence on flooding• On the previous slide, there was a picture of On the previous slide, there was a picture of

an urban landscape. What influence could an urban landscape. What influence could this have on flooding?this have on flooding?– Rapid transfer of water through the Rapid transfer of water through the

drainage and sewer systemsdrainage and sewer systems– The concrete surfaces do not allow water The concrete surfaces do not allow water

to absorb into the groundto absorb into the ground

• But so what? Should we care?But so what? Should we care?

Flooding: Should I be Flooding: Should I be bothered?!bothered?!• Flooding has always been a problem Flooding has always been a problem

for many places and recent high for many places and recent high profile flooding events has raised our profile flooding events has raised our awareness. Do you remember Newsawareness. Do you remember Newsfootage offootage of Boscastle in 2004 or Boscastle in 2004 or perhaps Bangladesh in the same perhaps Bangladesh in the same year? year? Boscastle flood footage Boscastle flood footage

• More recently, British settlements have suffered from More recently, British settlements have suffered from flooding and people have been left homeless whilst their flooding and people have been left homeless whilst their homes have been allowed to dry out and be repairedhomes have been allowed to dry out and be repaired

• This has meant that people have had to start paying This has meant that people have had to start paying higher prices for their house insurance, but how is this higher prices for their house insurance, but how is this price calculated?price calculated?

• Flood maps have been created by the Environment Flood maps have been created by the Environment Agency and anyone can now see if they live in a flood risk Agency and anyone can now see if they live in a flood risk zonezone

Insert image showing effects of flooding

e.g. Boscastle

Are you at risk Are you at risk of being of being flooded?flooded?

Tasks to completeTasks to complete

• Are you at risk?Are you at risk?• Lets have a look at the school first by using the website Lets have a look at the school first by using the website

http://www.environment-agency.gov.uk/subjects/flood/ and http://www.environment-agency.gov.uk/subjects/flood/ and by typing in the school postcode by typing in the school postcode

• Now have a look for yourself and find your own house. Now have a look for yourself and find your own house. Paste your map into a word document and label where Paste your map into a word document and label where your house is and annotate with information on what the your house is and annotate with information on what the flood risk is (your house should be in the middle of the flood risk is (your house should be in the middle of the map generated)map generated)

The House Price The House Price MysteryMystery

• On the following slide you will see four On the following slide you will see four pictures of houses and we are going to pictures of houses and we are going to work out the prices of themwork out the prices of them

• Before we do this, decide which would Before we do this, decide which would be your favourite house and why?be your favourite house and why?

£320,000 LOWER!£235,000

LOWER!£99,000!

LOWER!£160,000

What are the prices of these houses?

PO20 2HW4 bed

detached

PL35 0HA (4 bed attractive

location)

PO4 9PS (2 bed terrace

in city location)

CA1 2DD(3 bedroom terraced-

refurbished twice in the last

5 years)

Higher or Lower?Higher or Lower?

Insert images of houses of a variety of styles.NB: Houses shown do not have to correspond to the postcodes,

the idea is rather just to give a visual stimulus...

Environment Agency Flood Risk Environment Agency Flood Risk MapsMaps• Did you get them correct?Did you get them correct?• However, some key questions?However, some key questions?

– Which of the house prices surprised you?Which of the house prices surprised you?– Why has the final house been refurbished twice in the last 5 Why has the final house been refurbished twice in the last 5

years?years?– Why is the attractive harbour side house cheaper than the 4 Why is the attractive harbour side house cheaper than the 4

bedroom house found in a ‘normal’ village?bedroom house found in a ‘normal’ village?• Can we use the flood risk maps to help solve this Can we use the flood risk maps to help solve this

mystery?mystery?Use the weblink Use the weblink http://www.environment-agency.gov.uk/subjects/flood http://www.environment-agency.gov.uk/subjects/flood 1.1. Type the postcodes in for each of the four houses (Type the postcodes in for each of the four houses (PO20

2HW, PL35 0HA, PO4 9PS & CA1 2DD) and their location and their location will be exactly in the middle of the flood mapwill be exactly in the middle of the flood map

2.2. Paste the maps into a word document and suggest reasons for Paste the maps into a word document and suggest reasons for the differences in house pricethe differences in house price

3.3. For two of the houses, you might want to find out further For two of the houses, you might want to find out further information about flood events that have occurred recently- information about flood events that have occurred recently- these could form the basis of a detailed case studythese could form the basis of a detailed case study

Final thought provoking quote or image...?