Transcript Water used Wisely

Using Water Wisely
Chapter 11 section 4
S6E5.i Describe methods for
conserving natural resources such as
water, soil, and air.
• You will be able to ……………….…………
– Identify two forms of water pollution
– Describe two ways that wastewater can be
treated.
– Describe how water is used and how water can be
conserved in industry, in agriculture, and at home.
While hiking, you realize your canteen is almost
empty. Why should you not fill the canteen with
water from the nearby stream?
Even though the water may look clean, it might contain
pollutants or bacteria.
Water Pollution
• What is pollution?
• Where does the waste
come from?
• The introduction of
harmful substances into
the environment.
• Cities, factories, and
farms
Point-source pollution
• It comes from a specific
site.
• It can be controlled
because its source can
be identified.
Nonpoint-source pollution
• It comes from many
sources.
• Reaches bodies of water
by runoff.
• Examples: street gutter,
fertilizers, eroded soils,
salts from
irrigation.
Hardest
to
Control
Health of a Water System
Properties of water influenced
• Dissolved Oxygen (DO) – this is the
by water quality?
oxygen that is dissolved in water.
– Levels below 4.0 mg/L in can
cause stress and death for
organisms in the water.
– Sewage, fertilizer runoff, and
animal waste can decrease DO
levels.
– thermal pollution (increase in
water temperature) causes a
decrease in DO levels. Ex: nuclear
power plants
– Cold water holds more oxygen
than warm water
• Nitrates are naturally occurring compounds of
nitrogen and oxygen.
– Small amounts normal, elevated harmful
– Lower DO levels
– Examples: animal wastes or fertilizers that seep into
groundwater.
• Alkalinity refers to the water’s ability to neutralize
acid.
-too much acid (ph below 6.0), harmful to organisms living in
water.
Cleaning polluted water
• Sewage treatment plant
– A facility that cleans the
wasted materials found
in water that comes
from sewers or drains.
• Septic Tank
– A large underground
tank that cleans the
wastewater from a
household by separating
solid wastes from
liquids.
– Bacteria breaks down
the solid waste.
Where is
water used?
Home
Average 100
gal
per day
Industry
19%
Agriculture
Ways to Conserve water
>>>>>>Only use water that is needed<<<<<<
• Industry: recycle water
• Agriculture: drip
irrigation system
• Household:
Low-flow shower heads
and low-flush toilets,
time your showers, only
wash dishes and clothes
when there is a full
load.