flooding

Question 1

define flooding hazards (3)

Answer 1

described as the movement of water pr inundation of places where there is no previous coverage by water
one of the most common types of hazards
effects catastrophic affecting both natural and human environment

Question 2

list three types of flooding

Answer 2

riverine
urban/flash
coastal

Question 3

define riverine flooding

Answer 3

occurs when the river channel is unable to hold the volume of water entering the channel causing it to overflow the banks of the river resulting in flooding
most common cause - heavy and continuous rainfall over a short period of time

Question 4

define urban/flash flooding (4)

Answer 4

occurs most times in urbanised/built up areas
short lived where just as quickly the flood waters rise they recede just as quickly
rainfall events do not allow for infiltration of water into the ground because most surfaces are paved with asphalt and concrete
water flows over land into drains which cannot contain volume of water

Question 5

define coastal flooding (4)

Answer 5

often only occurs when coastlines or areas along the coast become inundated by either river or sea water that has been pushed up onto coast
may occur during high tides where water within river channel is unable to empty into the sea
water overflows banks of river channel flooding surrounding coastal area
strong storm surge formed during hurricanes push tall waved of water into coastal zone and inundating the entire coastline

Question 6

list five causes of flooding

Answer 6

littering and blocking of river courses and drains
poor drainage or lack of adequate drainage to carry water away
heavy rainfall
human activities such as paving roads and land surfaces which increases run offs of water
deforestation increases run off

Question 7

list 8 effects

Answer 7

loss of life
infrastructure damage
property damage
loss of time
agricultural produce loss
economic losses
health hazards
leads to landslides where flood waves undermine steep slopes

Question 8

list five structural ways to mitigate flooding

Answer 8

proper drainage - wider drains to hold large volumes of water
reafforestation -on hill slides reduce overland flow into rivers
coastal barriers - seawalls in Guyana to prevent coastal flooding
straightening of river courses to improve flow to the sea like cipero river
cleaning river courses and drains seasonally to improve capacity of holding water

Question 9

list five non structural ways to reduce flooding

Answer 9

legislation - antilittering laws to discourage persons from dumping
policies to protect hillsides and forests like the national forestry act and national hillside policy
public education campaigns to sensitise the public on how to prevent flooding
constructing flood hazard maps to inform about places susceptible to flooding
flooding insurance to safe guard and protect assets or replace them in flood situations