Transcript Water Pollution & Treatment

Do Now
Sit SILENTLY and answer the following
questions in your notes. Be sure to write
today’s date to ensure you are properly
organizing your notebooks for effective
studying.
 Describe how Christmas break was for
you and include what you enjoyed most
about it.
 What do you look forward to most this
coming semester?

Water Quality, Pollution, &
Treatment
Science 8
By : Mr. Miller
Standards: 8.E.1.3 – 8.E.1.4
Objective

SWBAT: Identify the different sources of
pollution and how we treat and clean
polluted water
What is Pollution?
A pollutant is any substance or form of
energy that can cause harm to the
environment and make it unfit for
organisms.
Two types of water pollution:
1. Point Source
2. Non-Point Source
Water Pollution Sources
 Point
Source- you know the one source
of pollution; it is identified; easier to
detect and control
 Non-point
Source- comes from many
sources that can not be easily identified;
harder to control
Point-Source examples:
Pipe from Sewage Plant
 Pipe from Industrial Factory

Point-Source examples:
Point-Source examples:

Oil Tanker Spill
Stop and Check #1

Why are these examples of point source
pollution?
Non-Point Source examples:
RUNOFF!!!
 Water comes from across a large, more
diffuse area of land
 From…farms, lawns, parking lots, streets,
construction sites, acid rain from air
pollution, etc.

Non-Point Source examples:
Non-Point Source examples:
Non-Point Source examples:
Non-Point Source examples:
Biomagnification/Bioaccumulation
Pollution gets into smaller organisms
 Amount builds up as it gets passed up food chain
 Chemicals could end up in food eaten by humans

North Carolina Main Sources of
Water Pollution

Sedimentation – increases turbidity
◦ Erosion
◦ Development
◦ Agriculture – tilling soil, irrigation, livestock
 Nutrient
Pollution – increases Nitrate &
Phosphate levels in water



 Increases Algae Lowers Oxygen
Fertilizers run off in storm water
Fecal Coliform Bacteria from animal feces
Water Treatment

Sewage Treatment Plants
◦ Process raw waste & get water ready to enter
back into rivers
◦ 1.) Sludge separated, chlorine used to kill
harmful bacteria
◦ 2.) Oxygen & sludge-eating bacteria used

Septic Systems
◦ Small wastewater system used by home or
business in rural area
◦ Sludge consumed by bacteria
◦ Cleaner water exits & spreads into ground
Septic System
Stop and Check #2

Which water treatment practice is
cleaner? Why?
Water Treatment
Drinking Water Treatment Plants:
 1. Water piped in from river or lake
 2. Flows through mixers, clumping agents
& chemical disinfectants added
 3. Clarifying pool separates large particles
 4. Filters separate tiny particles of dust &
dirt
 5. Chlorine used to kill bacteria
 6. Clean water goes to water storage tank

Stop and Check #3

What is an unintended additive that can
enter the urban water supply? (HINT:
Think about how the water has to travel
to storage towers and homes and
buildings)
EPA
The Environmental Protection Agency
sets and enforces water quality standards
for wastewater, pollution & drinking
water.
 Focuses on protection of surface
freshwater resources

What can we do to help?!
Pick up pet waste
 Pick up litter
 Plant vegetation
 Dispose of chemicals & wastewater
appropriately
 Reduce amount of water used

Exit Ticket
What are the 2 types of pollution? (I also
want a description of each, not just a
definition!)
 What are the two types of water
treatment methods and in your own
words describe which you believe to be a
better way to clean our water?
 Regardless of which method is better for
cleaning our water, what are some action
steps you can take to prevent water from
becoming so polluted?

Objective
SWBAT: Describe the different water
quality indicators
 SWBAT: Infer how humans impact water
systems and quality
 SWBAT: Connect the different indicators
and describe how they affect each other
and the animals living in those
environments.

What are water quality indicators?
Water quality indicators tell us how pure
a sample of water is by measuring how
many substances are dissolved or mixed
in with the water.
 They are a set of indicators that people
routinely test to determine the safety of
drinking water as well as measuring
environmental impact by humans.

What water quality indicators can tell
us…

Water quality determines the sustenance
of ecosystems and human activity
including: agriculture, fishing, and
recreation, as well as public health of
human societies. Water quality testing
supports healthy environments in which
rich and varied communities of organisms
can be found.The importance of
monitoring and maintaining water quality
cannot be overstated.
Stop and Check #1

What human activities could lead to the
need to test water quality in the first
place?
How we measure water quality indicators
PARTS PER MILLION
Most dissolved substances found in
water are measured in parts per
million (ppm) or even smaller
amounts. This means that for every
one million parts (units) of water
there is a certain number of parts of
the substance.
Concentrations of certain
substances are also measured in
parts per billion, parts per trillion
and so on. These are very small
amounts but certain substances
can be harmful even at these very
low concentrations.
Water Quality Indicators
We will now
take a look
at the water
quality
indicators.
#1 ALKALINITY
Alkalinity refers to the water’s
ability to neutralize acids.
Alkalinity is
produced by
minerals such as
limestone.
Limestone is a type of ocean
sediment composed of calcium
carbonate.
Limestone bedrock areas often have
caves and sinkholes, known as Karst.
Water with
low
alkalinity is
usually
acidic.
#2 Ammonia
 Ammonia
is produced by the decay
of organic matter and animal waste.
 Ammonia is toxic to most aquatic
life, especially at high pH.
 Bacteria readily convert ammonia to
nitrate. (a plant nutrient)
Ammonia
Ammonia is
a form of
nitrogen
and part of
the
Nitrogen
Cycle.
#3 BACTERIA
Most bacteria are important in nutrient and
other organic cycles.
Excess nutrients
cause algal
blooms. As algae
die and decay, the
high bacterial load
rapidly consumes
dissolved oxygen.
Certain types of bacteria
indicate animal and human
waste pollution.
Escherichia coli are coliform
bacteria found in the intestines
of warm-blooded organisms.
Most strains are harmless but
one E. coli strain can cause
severe diarrhea and kidney
damage.
Stop and Check #2
What human activities could contribute
to an increase in ammonia and bacteria?
 Since nitrates provide plants with food,
what other process could happen as a
result of increased ammonia that could be
detrimental to the lake or pond?

# 4 DISSOLVED
OXYGEN
Dissolved oxygen
is a product of
photosynthesis
and diffusion.
The warmer the water, the less
oxygen it can hold.
Why do you think that is?
DISSOLVED OXYGEN
Most organisms
need at least 5
or 6 ppm of
oxygen in order
to survive.
Even cold water rarely contains
more than 15 ppm. Summer is
often a time of oxygen stress for
aquatic organisms.
Stop and Check #3
What do you think are the major
contributors of dissolved oxygen in water
ecosystems?
 How can these organisms be bad for
the water ecosystem?

#5 CONDUCTIVITY
Conductivity measures the
water’s ability to conduct an
electrical current.
Pure water is a poor
conductor.
Why do you think that is?
CONDUCTIVITY
The addition of dissolved
solids, especially salts,
increases the conductivity of
water.
Electrical current is measured using a
conductivity meter.
# 6 HARDNESS
Hardness refers to the
concentration of calcium and
magnesium in water.
Hard water has high concentrations of
these elements. Soft water has low
concentrations.
Water hardness often originates
from limestone.
Stop and Check #4
If water hardness is due to water coming
into contact with limestone, what other
water quality indicator could we
measure?
 Why does it make sense that we can
measure this other quality of water?
(HINT: think about where the elements
that cause water hardness are on the
periodic table and what group they are
in.)

HARDNESS
Area of the U.S. with limestone
bedrock have hard water.
Hard
Water
Exit Ticket
Describe how ammonia affects water
quality and why it is important to test for
it.
 Describe how oxygen levels can be
increased or decreased in a water system.
 What are the main contributing
ELEMENTS to water hardness? Where
does water usually get more of these
elements?

# 7 NITRATE
Nitrate is a primary
plant nutrient.
Nitrate is water
soluble and moves
easily from surface
to groundwater.
Excess nitrate causes algal
blooms that reduce water quality.
Under normal conditions, the nitrogen
cycle keeps the amount of available
nitrogen in balance with the demands.
However, excessive use of fertilizers
and nutrient rich sewage release have
created a surplus of nitrate. The result
is eutrophication from excess algae
and bacteria. This reduces dissolved
oxygen.
PESTICIDES
These chemicals are very
complex. They can affect many
indicators of water quality but
mainly increase nitrates and pH.
Effects on aquatic
organisms – Moderately to
highly toxic to mammals,
molluscs, aquatic insects,
amphibians and fish.
Stop and check # 5
What are some ways that nitrates are
increased in fresh water supplies?
 What is the term for this process?

# 8 pH
pH is the measure of the hydrogen ion (H+)
concentration.
The pH scale is zero to 14. Seven
is neutral, below seven is acidic,
and above seven is basic (or
alkaline).
Most aquatic organisms exist
within a pH range of 5.5 to 9.5.
pH tolerance
for most
aquatic life
Stop and Check # 6

How can water become more BASIC or
ALKALINE and what elements on the
periodic table contribute to this change?
# 9 Phosphate
Phosphate’s concentrations in
clean water is generally low;
however, phosphorus is used
extensively in fertilizer and other
chemicals.
Runoff carrying phosphorous
from fertilizer is the main
contributor to this indicator.
Phosphate
The primary sources of
phosphates to surface water are
detergents, fertilizers, and
natural mineral deposits.
Phosphate
High levels of phosphate can
over stimulate the growth of
aquatic plants and algae.
This in turn, will cause high DO
consumption and death to fish
and many aquatic organisms.
Stop and Check # 7

What are the two main water quality
indicators that contribute to lake
turnover or EUTROPHICATION?
# 10 Salinity
Salinity refers to the salt
concentration in water,
mostly sodium chloride.
Salinity is historically
measured in parts per
thousand (ppt) or grams
per liter.
Salinity
Saltwater can cause problems when it
replaces fresh groundwater near the
coastal areas.
#11 TEMPERATURE
Temperature is measured in
Fahrenheit and Celsius degrees.
Temperature can be measured
using field thermometers but
digital probes are much more
accurate.
Most aquatic organisms live
within a temperature range of
+32º F (+0º C) to 90º F (32º C).
Rapid temperature change and
temperature extremes can stress
aquatic organisms.
Temperature affects the oxygencarrying capacity of water.
14
Dissolved Oxygen (ppm)
12
10
8
6
4
____________________________________
Winter
Summer
As the water warms, the
amount of dissolved
oxygen decreases.
Stop and Check #8

Why can water hold more oxygen the
colder is gets? (HINT: think about the
structure of water)
# 12 TURBIDITY
Turbidity
refers to
water
clarity.
Sediments
suspended in
the water
increase
turbidity.
A secchi disk is one type of
instrument used to measure
turbidity.
Sediment
Erosion causes
loose soil to
enter the
waterways
Sediment
Suspended sediment blocks
sunlight to plants and reduces
dissolved oxygen.
As sediments settle, they can
smother bottom (benthic)
organisms.
TOTAL DISSOLVED SOLIDS (TDS)
TDS is the measure of the
material dissolved in water.
This measure is related to
hardness, salinity and
conductivity.
Hard water has more TDS than
soft water.
Why do you think that is?
TOTAL SUSPENDED SOLIDS
(TSS)
TSS is the measure of the
sediment suspended in the
water.
TSS is related to turbidity.
Water with high TSS usually has
high Total Dissolved Solids (TDS)
as well.
TOXIC CHEMICALS
Toxic chemicals usually come
from industry and energy
production.
The effects are often not
known until years after they
have entered the
environment.
Toxic chemicals include heavy
metals (lead, mercury),
organic compounds (DDT,
PCB), inorganic substances
(arsenic) and others.
Exit Ticket
How are sediments and turbidity related,
and how can the two affect wildlife in
extremely turbid environments?
 What are the main contributors to
changes in pH in water systems and how
are humans mainly responsible for this?
 Why is there a decrease in oxygen
dissolved in water as it gets warmer?
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