Pick a Number to Reveal the Picture!

1
Pick a Number to Reveal the Picture!
2
Insert image of Cadair Idris or similar
steeply sloped landform
Info
Back
3
CHALK ROCK
Insert image of Chalk Rock
V
Insert image of Granite Rock
GRANITE ROCK
Info
Back
4
Insert image of woodland
V
Insert image of heather moorland
Info
Back
5
Insert OS map that shows area with many
streams
V
Insert OS map that shows area with one river
and few or no streams
Back
Info
6
Insert image of cumulonimbus cloud(s)
Back
Info
V
Insert image of nimbostratus cloud(s)
7
STEEP SLOPES
Insert image of Cadair Idris or similar
steeply sloped landform
The steep slopes found on (e.g. Cadair Idris)
results in a rapid transfer of water into the
Nant Cadair stream

• A drainage basin with steep slopes will result in
  any precipitation rapidly entering the river
  channel
• This will result in the peak flow (discharge) of
  the river being high and responsive in that it
  will reach peak discharge quickly and then fall
  away quickly once the rainfall event has ended

Back to Picture
Back to Picture Board
8
GEOLOGY
The granite (below) is impermeable and as a
result drainage basins with rocks of this type
will promote rapid runoff and could lead to
flooding
Insert image of Chalk Rock
Insert image of Granite Rock

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

Back to Picture Board
Back to Picture
9
Vegetation
Insert image of woodland

• Vegetation can influence river flooding
• If a drainage basin has woodland like in the top
  picture, then more of the rainfall will be
  intercepted and subsequently lost due to
  evavoptranspiration
• If little vegetation is present, more water will
  enter the river and promote a higher peak
  discharge

Insert image of heather moorland
Back to Picture Board
Back to Picture
10
Drainage Density
Insert OS map that shows area with many
streams

• Some areas have a high number of streams draining
  the land, whereas other have very few.
• These differences in drainage density will
  result in differences in the speed in which water
  is transferred and therefore the potential flood
  risk

• The map of (e.g. Snowdonia) above has many
  streams and a high drainage density ( steeper
  slopes)
• The (e.g. River Meon) is the only river on the
  bottom map- it has a low drainage density

Insert OS map that shows area with one river
and few or no streams
Back to Picture Board
Back to Picture
11
Cloud types and rainfall
Insert image of cumulonimbus cloud(s)
Back to Picture
Back to Picture Board

• The cumulonimbus cloud at the top will produce
  intense torrential rain which has the potential
  to produce serious flooding
• The Nimbostratus clouds on the right are normally
  associated with light drizzle

Insert image of nimbostratus cloud(s)
12
Insert image of dense urban
environment
13
Urbanisation Human Influence on flooding

• On the previous slide, there was a picture of an
  urban landscape. What influence could this have
  on flooding?
• Rapid transfer of water through the drainage and
  sewer systems
• The concrete surfaces do not allow water to
  absorb into the ground
• But so what? Should we care?

14
Flooding Should I be bothered?!

• Flooding has always been a problem
• for many places and recent high
• profile flooding events has raised our
• awareness. Do you remember News
• footage of Boscastle in 2004 or
• perhaps Bangladesh in the same
• year? Boscastle flood footage
• More recently, British settlements have suffered
  from flooding and people have been left homeless
  whilst their homes have been allowed to dry out
  and be repaired
• This has meant that people have had to start
  paying higher prices for their house insurance,
  but how is this price calculated?
• Flood maps have been created by the Environment
  Agency and anyone can now see if they live in a
  flood risk zone

Insert image showing effects of flooding e.g.
Boscastle
15
Are you at risk of being flooded?

• Tasks to complete
• Are you at risk?
• Lets have a look at the school first by using the
  website http//www.environment-agency.gov.uk/subje
  cts/flood/ and by typing in the school postcode
• Now have a look for yourself and find your own
  house. Paste your map into a word document and
  label where your house is and annotate with
  information on what the flood risk is (your house
  should be in the middle of the map generated)

16
The House Price Mystery

• On the following slide you will see four pictures
  of houses and we are going to work out the prices
  of them
• Before we do this, decide which would be your
  favourite house and why?

17
Higher or Lower?

What are the prices of these houses?
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...
PO20 2HW 4 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)
320,000
LOWER! 235,000
LOWER! 99,000!
LOWER! 160,000
18
Environment Agency Flood Risk Maps

• Did you get them correct?
• However, some key questions?
• Which of the house prices surprised you?
• Why has the final house been refurbished twice in
  the last 5 years?
• Why is the attractive harbour side house cheaper
  than the 4 bedroom house found in a normal
  village?
• Can we use the flood risk maps to help solve this
  mystery?
• Use the weblink http//www.environment-agency.gov
  .uk/subjects/flood
• Type the postcodes in for each of the four houses
  (PO20 2HW, PL35 0HA, PO4 9PS CA1 2DD) and their
  location will be exactly in the middle of the
  flood map
• Paste the maps into a word document and suggest
  reasons for the differences in house price
• For two of the houses, you might want to find out
  further information about flood events that have
  occurred recently- these could form the basis of
  a detailed case study

19
Final thought provoking quote or
image...?