2.2 How do
human activities
influence water
supply and
demand?
Water
Demand in
England
The population in 2001 was at
8,000,550, in 2011 it was at
8,634,800.
An average of 167 litres per day is
the avg. domestic consumption
compared to an average of 151
litres per day in England and
Wales.
The economy is second to
London and is expanding at a rate
of 3.1% annually compared to
2.2% nationally. As a result, the
region has a higher consumption
of water for industrial use than any
other region in England and
Wales.
Due to climate change, a
reduction in summer
rainfall of 8-23% is
predicted and an increase
in winter rainfall of 6-22%.
Solutions for the increasing water demand
Reservoirs are
planned after 2020 in
S.E England.
Reservoirs can also
be used for wildlife
conservation,
recreation, flood
control.
It takes a long time to plan
and is expensive. It can
damage the surrounding
environment. Water may
not be able to be taken out
of the river if levels are
already low
A large scale desalination
plant in London was
opened in 2010. The £270
London facility was
opened as a safeguard
against water shortages.
Britain is
surrounded
by sea so
saltwater is
in unlimited
Disposing the
concentrated
brine unsafely
could harm the
environment
River
Severn-River
Thames
water
transfer
This involves abstracting
water from the lower River
Severn near Deerhurst and
discharging it into the upper
River Thames at Buscot. Then
the water from the Thames
would convey water
downstream into existing
reservoirs near London.
An option of a 90km pipeline
from Deerhurst direct to
London reservoirs is an option
to avoid mixing foreign water to
the Thames. This project would
cost at least £117 million, and
a storage area would have to
be built in Deerhurst.
The hydrochemistry of
the rivers would change
which would affect the
quality of the water and
the organisms that live
there.
Thames Water Utilities Ltd.
(Thames Water) is a private
utility company responsible
for water supply and waste
water treatment in the
London and the Thames
Valley.
The company supplies
around 2.6 giga litres of
drinking water a day from
100 water treatment
centres through 32,000 km
of managed water mains to
8.7 million customers
It removes and treats
2.8 giga litres of
wastewater from 13.8
million customers to
349 sewage treatment
works across the south
of England.
2.3: How can water
supply and demand
be managed
sustainably?
Water
infrastructure
in Singapore
Singapore has a population of 5.4 m.
The country has suffered from water
shortages although it receives 2,400
mm of ppt, this is because of its
limited storage area. Malaysia
supplies freshwater, but the
agreement will end in 2064 and the
prices has been increasing.
Public Utilities Bureau is
now in charge of water
issues in Singapore. In
1998, they proposed the
NEWater Study which is
water that has
undergone stringent
purification and
treatment process using
advanced
dual-membrane
(microfiltration adn
reverse osmosis)
The water produce now
accounts for about 15%
(about 90 million m3/day)
and will provide 30% of the
total water supply in the city
state by 2010.
SingSpring SWRO
Plant, the first
desalination in the
country, began to be in
operation in September
2005. It supplies 10%
of the total water
supply in the country
with a capacity of 136
m3/day. By 2011, it will
increase to 30%.
Thames
Region
Artificial recharge of the London
Basin groundwater supply;
inter-regional transfer from the River
Severn and the Anglian Region;
groundwater development;
desalination of saltwater in the
Thames Estuary; re-use of effluents
presently discharged into the
Thames Estuary; reservoir storage in
the SW Oxfordshire.
The total volume
of groundwater that
is allowed to be
extracted is over
2305 million
litres/day of which
about 85% is used
for potable supply
2/3 of the
catchment is
permeable and
thus subject to
direct recharge
from rainfall.
Pollutants can
then infiltrate into
the ground
Water efficient
appliances such as
low-water use
washing machines,
low flush toilet
cisterns and
water-wise
gardening products.
The growth in
tourism and
recreation will
increase the
demand for
water, e.g.
restoration of
disused canals
will put a
pressure on
wtater
resources.
Less
rainfall,
690 mm,
the
national
avg. is
800 mm
2.4: Can sustainable
water supplies be
maintained in the
future?
Desalination
The salt is taken out to end up
with pure water, the chemicals
used and other by-products can
harm the environment if not
disposed of in the right way
Socially sustainable as
families can operate
small-scale desalination
plants if water is scarce.
Water
Recycling
Socially sustainable for
use in agriculture and
industry, however if used
for drinking, the procedure
should be stricter
Environmentally
sustainable, as the
water is reused which
reduces the demand.