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Lesson Plan 15
Time: 1 hour
Title: Water Testing and Analysis
Learning Expectations:
1. Describe physical, biological and chemical contaminant tests and indicators for
water quality
2. Identify common test procedures and equipment for bacteriological tests
3. Explain the appropriateness of water testing
Materials Required:
 Turbidity tube

Water testing technologies
Topics and Key Points
1.




Learning
Strategies
Water Tests and Indicators
Bacteriological: e.coli, fecal coliforms
Chemical: fluoride, arsenic, heavy metals
Physical: pH
Other: salinity, turbidity, colour
2. Water test options
1. Physical test:
 Turbidity tube (low cost option), Colour , Smell
2. Chemical tests:
 Colorimeter (reagent and colorimeter)
 Test kits (test cubes, reagents)
3. Bacteria tests: (most useful)
 membrane filtration
(filter apparatus, incubator, miro-filter paper, media broth,
etc.)
- pump water sample through micro-filter paper, place
filter paper in Petri dish with broth, incubate for 24 hours
at 35C and then count individual bacteria colonies
 most probable number (already prepared dish with
reagents included)
 presence/ absence (indicator strip, UV lamp)
- place indicator strip in water sample, observe for colour
change
 petrifiltm
PPT
(Day
4-7 –
Short)
1-19

Facilitator led
with
demonstrations
Time
(min)
5
25
3. Field Lab
 Considerations: size, weight, batter operated, airport
security, locally available,
5
4. Applications
 Testing may be to expensive and may not really be needed
 May be useful to convince users of need or of benefits
5
5. Review
Reflection: