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Do NowDo NowSit 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, Water Quality, Pollution, & Pollution, & TreatmentTreatmentScience 8By : Mr. MillerStandards: 8.E.1.3 – 8.E.1.4
ObjectiveObjectiveSWBAT: Identify the different sources of pollution and how we treat and clean polluted water
What is Pollution?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 Water Pollution SourcesSourcesPoint 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:Point-Source examples:
Pipe from Sewage PlantPipe from Industrial Factory
Point-Source examples:Point-Source examples:
Point-Source examples:Point-Source examples:Oil Tanker Spill
Stop and Check #1Stop and Check #1Why are these examples of point source pollution?
Non-Point Source Non-Point Source examples: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 Non-Point Source examples:examples:
Non-Point Source Non-Point Source examples:examples:
Non-Point Source Non-Point Source examples:examples:
Non-Point Source Non-Point Source examples:examples:
Biomagnification/Biomagnification/BioaccumulationBioaccumulationPollution 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 North Carolina Main Sources of Water Sources of Water PollutionPollutionSedimentation – increases turbidity◦Erosion◦Development◦Agriculture – tilling soil, irrigation, livestock
Nutrient Pollution – increases Nitrate & Phosphate levels in water
Increases Algae Lowers OxygenFertilizers run off in storm waterFecal Coliform Bacteria from animal feces
Water TreatmentWater TreatmentSewage 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 SystemSeptic System
Stop and Check #2Stop and Check #2Which water treatment practice is cleaner? Why?
Water TreatmentWater TreatmentDrinking Water Treatment Plants:1. Water piped in from river or lake2. 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 bacteria6. Clean water goes to water storage tank
Stop and Check #3 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)
EPAEPAThe 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 What can we do to help?!help?!Pick up pet wastePick up litterPlant vegetationDispose of chemicals & wastewater appropriately
Reduce amount of water used
Exit TicketExit TicketWhat 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?
ObjectiveObjectiveSWBAT: 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 What are water quality indicators?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 What water quality indicators can tell us…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 #1Stop and Check #1What human activities could lead to the need to test water quality in the first place?
PARTS PER MILLIONMost 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.
How we measure water quality indicators
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 IndicatorsWater 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 Limestone bedrock areas often have caves and often have caves and sinkholes, known as Karst.sinkholes, known as Karst.
Water with low alkalinity is usually acidic.
#2 #2 AmmoniaAmmoniaAmmonia 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)
AmmoniaAmmonia
Ammonia is a
form of nitrogen and part of the Nitrogen Cycle.
#3 BACTERIAMost 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 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 #3Stop and Check #3What 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?
CONDUCTIVITYThe 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 #4Stop and Check #4If 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 TicketExit TicketDescribe 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 # 5Stop and check # 5What are some ways that nitrates are increased in fresh water supplies?
What is the term for this process?
# 8 pHpH 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 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 # 7Stop and Check # 7What 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.
SalinitySaltwater can cause
problems when it replaces fresh groundwater near the coastal areas.
#11 TEMPERATURE
Most aquatic organisms live within a temperature range of +32º F (+0º C) to 90º F (32º C).
Temperature can be measured using field thermometers but digital probes are much more
accurate.
Temperature is measured in Fahrenheit and Celsius degrees.
Temperature affects the oxygen-carrying capacity of water.
Rapid temperature change and temperature extremes can stress
aquatic organisms.
As the water warms, the amount of dissolved oxygen decreases.
14 Dissolved Oxygen (ppm)
12
10
8
6
4____________________________________ Winter Summer
Stop and Check #8Stop and Check #8Why can water hold more oxygen the colder is gets? (HINT: think about the structure of water)
# 12 TURBIDITYTurbidity refers to
water clarity.
Sediments suspended in
the water increase turbidity.
A secchi disk is one type of instrument used to measure
turbidity.
SedimentSediment
Erosion causes
loose soil to enter
the waterways
SedimentSediment
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 TicketExit TicketHow 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?