Water were does it come from and

why do we need it!

http://www.epa.gov/ogwdw/watertreatmentplant/flash/index.html

Water Quality Water Quality: used to describe the health of a water system.

Health of water is determined by:1. chemical variables/properties2. physical variables/properties3. biological (environmental

stressors)/properties

Physical Variables include

1. Temperature– Low 32°F– High 97°

2. Turbidity (NTU): a measure of the clarity of the water (how clear is it?) Turbidity (NTU) is often measured by using a Secchi Disk: A flat, white disk lowered into the water by a rope until it is barely visible. At this point, the depth of the disk from the water surface is the recorded secchi disk transparency.

3. Water Movement

Nephelometric Turbidity Units (NTU):

• 1 NTU – Ideal level•5 NTU - High level

Chemical Variables include1. Dissolved Oxygen (DO) and other gases– Dissolved Oxygen: measure of water quality indicating free

oxygen dissolved in water. (average level 9.0 ppm)– Must be 4 – 5 ppm to support diverse population of fish

2. pH: The measure of how acidic or basic a substance the acidity, neutrality or basic of a substance.

3. Nitrates: nitrogen compounds used for growth by plants and algae; a compound that can be used by photosynthetic life forms to obtain the nitrogen needed for survival. (drinking water 10mg/l & 90 mg/L warm water fish tolerate)

4. Salinity

Environmental Stressors:

1. Urban runoff

2. Agricultural runoff

3. Industrial inputs

4. Over fishing – impacts populations

Results of Environmental Stressors

1. Decrease in diversity

2. Elimination of intolerant organisms

3. Increase in tolerant organisms

• Toxic influx and nutrient enrichment causes chemical and environmental changes.– Major shift in plant and animal life

Using technology to monitor water quality will help humans provide treatments to improve conditions in Earth’s oceans and freshwater.

Technology and Indicators used:

pH scale: rating of how acidic or basic a substance is; the scale goes from 0 to 14 with 7 being neutral values less than 7 being acidic and values greater than 7 being basic. (surface water 6 – 9; salt water 7.7 – 8.1)

Technology and Indicators used: (cont.)

• Bioindicator: Organisms or components of organisms that are used to assess the health of a water system; an organism or community associated with particular environmental conditions a change to the number of organisms or the proportions of the community indicate a change in the environment.

• Indicator: A chemical material or solution which can be used to show (usually by a change in color) the endpoint of a chemical reaction or chemical concentration. Examples: Litmus and Phenolphthalein

Technology and Indicators used: (cont.)

• Macro-invertebrate: small, spineless creatures that are visible with the unaided eye; they include organisms such as Crustaceans, mollusks, worms, and insects.

Six Main Indicators Activity

Handout

Formative Assessment

LAB

• 1. What would you do with this water

• 2. pH and our Environment

ActivityCooperative Learning

The Fish Kill MysteryWith

Handout