Transcript Environmental_Science_files/water quality

Water Quality
Environmental Science
Mr. Mead
Water Quality
• Water Quality is a very general term
explaining how safe the water is for
consuption, contact, and the wildlife that
depends on it.
• Almost an immeasurable amount of things
can and do effect water quality
• DQ - name a few.
• Pollution, runoff, rain, erosion, wildlife,
bacteria, human needs, time of year, location,
sunlight, …
Water Pollution
• An obvious thing that can effect water
quality is pollution
• Water pollution - anything that
degrades water quality
• Can be physical (ex. sedimentation),
biological (ex. Bacteria), or chemical
(ex. Nitrogen)
Water Pollution
• There are two types of sources of pollution.
• Point - meets the body of water at a specific
location
• Examples?
• Nonpoint - have no specific location where
they discharge into the body of water.
• Examples?
• DQ - Which would be harder to control
and why?
Water pollution
• There are two main categories of
pollutants based on what their effects
are.
• Each of these categories have
subcategories as well.
• 1. Causes Health Problems
• 2. Causes Ecosystem Disruption
Causes Health Problems
• Subcategories - and sources
• 1. Infectious agents - human waste
• Bacteria, viruses, parasites
• 2. Organic Chemicals - industrial waste, farms
• Pesticides, plastics, oil
• 3. Inorganic Chemicals - Industrial waste,
household cleaners
• Acids, salts, metals
• 4. Radioactive Materials - mining, power
plants
• Radon, uranium, etc.
Health problems
• These are a huge problem in developing
countries
• But still some problems here in US as
well as many other developed countries
• Ex. China
• We will worry less about this category,
because it deals more with humans
Ecosystem Disruption
• Subcategories - and sources
• 1. Sediment - Land erosion
• Soil, silt
• 2. Plant Nutrients - fertilizers, sewage
• Nitrates, Phosphates, Ammonium
• 3. Oxygen demanding waste - Sewage, food
processing
• Animal manure, paper waste
• Thermal - power plants, industrial cooling
• Heated water
Ecosystem disruption
• DQ - How do each of these disrupt
the ecosystem?
• Look in your book to answer this question
• Sediment
• Clouds water, not allowing
photosynthesis to take place
• Lowering oxygen levels, and less food
• Covers gravel beds for fish spawning
Ecosystem disruption
• Plant nutrients
• Eutrophication - too many nutrients
• Blooms of algae and other aquatic plants
• When these die, oxygen levels tank
• Raise bacteria levels
• Cause funny taste and/or odor of water
• Oxygen demanding waste • Lower oxygen levels, killing off species
• Can add bacteria and affect taste
Ecosystem Disruption
• Thermal
• Aquatic organisms not adapted well to
temp. changes
• Oxygen levels are affected
• Some animals are attracted to thermal
plume during winter months
Water Quality Today
• In the USA we have legislation trying to
keep our water clean and safe.
• The overall water quality of surface
water in America has improved
dramatically in the last 30-40 years.
• We have set standards of “acceptable”
levels of different substances in our
waters.
Water Standards
• All states a little bit different
• These are Iowa DNR standards
• Nitrates
• 15 ppm - maximum level to be considered
“healthy” water
• 3-10ppm = optimum range
• In drinking water it shouldn’t be more than
5 ppm
Water Quality Standards
• Phosphorus
• 30 ppm - maximum level to be considered
“healthy” water
• 5 - 15 ppm - optimum range
• Ammonium
• 5 ppm - max level
• 1-3 ppm - optimum range
• Turbidity - how clear the water is
• How much light gets through the water
• http://dipin.kent.edu/tsi.htm
Water Quality Standards
• pH
• Standard 7.0 - 8.3
• Life can survive 6.0 - 9.0
• Nitirite
• 10 ppm - max level to be considered safe
• 2 ppm - 6 ppm optimum range
• Dissolved Oxygen
• 0-2 ppm - fish can’t survive, little advanced life
• 2-5 ppm - Rough fish (carp, catfish) invertabrates
• 5-10 ppm - Healthy Ecosystem
Activity
• In your notes, write a short paragraph
to explain why the optimum range for
these chemicals would not be 0 ppm.
Water Quality Today
• The USA has improved its water quality
dramatically the last 30 years.
• However, other countries have not had as
much luck with water quality.
• China - over half of the water is not suitable
for any human use because of pollution.
• Russia - only half of tap water is fit to drink
straight from tap
• Developing countries - use their water
sources as bathrooms, and landfills
Sources of Freshwater
• Surface water
• Rivers, Streams, Lakes, etc.
• Needs to be treated with several steps
• Groundwater
• Aquifers - filtered by the soil
• Usually cleaner, but once polluted, very hard to
clean.
• Ocean Water
• Needs to be desalinated before it can be used
Water Quality Today
• Overall water quality in the world is
decreasing because of these problems
• Snowball effect
• Little water available because we have
polluted many sources
• But good sources get polluted by our over
use of them, since there is so little water
Solutions
• Try to increase amount of fresh water
• Can take a long time
• Not cost effective
• Clean polluted water
• Hard to do
• Expensive
• People still don’t trust it
• Conservation
• Most people don’t want to do it
What can you do?
• Activity - list 8 things that you can do to
help improve water quality?
• Conserve
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Don’t let water run when brushing teeth
Don’t water lawn
Low flow showers, shower less
Fix leaky faucets/toilets
Don’t flush every time
Wash large loads of laundry
What can you do?
• Reduce pollution
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Don’t dump chemicals down drain
No fertilizer on lawn
Car pool
Compost yard waste
Fix leaky car
Organize river clean up groups
Assignment
• Write a paragraph choosing one of the
three solutions that you believe makes
the most sense
• Write a second paragraph explaining
the quality of your water sample, based
on the levels of each that you found.