WaterWater QualityQualityWaterWater QualityQuality

What does it mean?What does it mean?What does it mean?What does it mean?

Water quality is the ability of a water Water quality is the ability of a water body to support all appropriate body to support all appropriate

beneficial uses.beneficial uses.

Water quality is the ability of a water Water quality is the ability of a water body to support all appropriate body to support all appropriate

beneficial uses.beneficial uses.• Beneficial uses for Beneficial uses for

humans:humans:• drinking waterdrinking water• bathing bathing • food preparationfood preparation• sanitationsanitation

• Beneficial uses for Beneficial uses for animals:animals:

• habitathabitat• drinking waterdrinking water• reproductionreproduction

Assessing Water QualityAssessing Water QualityAssessing Water QualityAssessing Water Quality

• Physical Physical AssessmentsAssessments

• Chemical Chemical AssessmentsAssessments

• Biological Biological AssessmentsAssessments

Physical AssessmentsPhysical Assessments

• TemperatureTemperature• DepthDepth• Flow rateFlow rate• TurbidityTurbidity• Environmental Environmental

factorsfactors• trees, stream bed, soil, trees, stream bed, soil,

vegetation, vegetation, topography, man-made topography, man-made surfaces/structuressurfaces/structures

Chemical AssessmentsChemical AssessmentsChemical AssessmentsChemical Assessments

• Acidity/Alkalinity - pHAcidity/Alkalinity - pH

• Dissolved OxygenDissolved Oxygen

• Chemical pollutants Chemical pollutants - fertilizers (NO- fertilizers (NO33, , POPO44)detergents, heavy metals, etc.)detergents, heavy metals, etc.

• Biological Oxygen DemandBiological Oxygen Demand

• Coliform BacteriaColiform Bacteria

Measured in terms of concentration; parts per Measured in terms of concentration; parts per million or milliliters per gallonmillion or milliliters per gallon

Measured in terms of concentration; parts per Measured in terms of concentration; parts per million or milliliters per gallonmillion or milliliters per gallon

Biological AssessmentsBiological Assessments

• Macroinvertebrate diversity

• aquatic insects, insect larvae, crustaceans, and other smaller animals that spend their lives in water

• number and distribution of species

• levels of sensitivity by species - level 1, 2 & 3

Guiding QuestionsGuiding Questions

• How do stream ecosystems respond physically, biologically and chemically to urbanization?

• How do we measure the quality of water in nature?

• How is water quality affected by urban environments?

• How are stream ecosystems in Kathmandu and Lexington alike and different?

• How do we use water quality information to promote sustainability of urban environments and urban stream ecosystems?

Activity SuggestionsActivity Suggestionso Make a map for a certain radius around your home showing

different kinds of urban environments; residential, shopping, parks, office buildings, industrial areas.

o Construct food web diagrams for some ecosystems in your area.

o Explore the question of whether your city or community has too many people. Can your local ecosystem support the population for the foreseeable future? What are the advantages of having more or less people?

o Interview grandparents or others that have lived in your area for a long time. How have natural, agricultural and urban ecosystems changed? Compare a map of your community from 50 years ago with a current map.

International International ConnectionsConnections

•L.R.I. (Learning L.R.I. (Learning Realm Realm International)International)

•Ullens SchoolUllens School

Kathmandu, Nepalprivate schools