Flash Flooding
 
Flash
floods
usually
happen
during
heavy rainfall,
when
 
the
amount
 
of
water
is
too much
for
drains
 
 
and
sewers
 
to
 
deal
with.
 
 
It
can
occur
very
quickly
 
and
without
much
warning.
Roads
can
become
unpassable,
with
vehicles
abandoned.
Homes
 
and
shops
become
damaged
 
by
floodwater.
Urban
areas
have
a lot
 
of
hard
surfaces
 
and
so
are
affected
more.
This
is
because
when
rain
hits
them
 
 
it
can't
soak
into
 
the
ground
as
 
it
would
 
do
 
in
 
the
countryside.