Water PollutionWater Pollution

Types and Sources of Water PollutionTypes and Sources of Water Pollution

#1 problem - Eroded soils#1 problem - Eroded soils

Organic wastes, disease-causing agentsOrganic wastes, disease-causing agents

Chemicals, nutrientsChemicals, nutrients

Radioactive stuff, heatRadioactive stuff, heat

Point and Nonpoint SourcesPoint and Nonpoint Sources

NONPOINT SOURCES

Urban streets

Suburban development

Wastewater treatment plant

Rural homes

Cropland

Factory

Animal feedlot

POINT SOURCES

Major Problem: Drinking WaterMajor Problem: Drinking Water

Safe Drinking Water Act

Safe Drinking Water Act

EPA: Maximum contaminant levels (municipal, but not rural and private)

EPA: Maximum contaminant levels (municipal, but not rural and private)

1/2 of world’s people drink polluted water

1/2 of world’s people drink polluted water

Pollution of Surface Water: StreamsPollution of Surface Water: Streams D.O., B.O.D., fecal coliform bacteria count D.O., B.O.D., fecal coliform bacteria count

Pollution of Surface Water: LakesPollution of Surface Water: Lakes

Cultural eutrophication Cultural eutrophication

Slow turnover

Slow turnover

Accumulation of nutrients, excessive plant growth, algae blooms

Accumulation of nutrients, excessive plant growth, algae blooms

Case Study: The Great LakesCase Study: The Great Lakes

MississippiRiver Basin

MissouriRiver

OhioRiver

MississippiRiver

LOUISIANAMississippi

River

Depleted

Oxygen

Gulf of MexicoDead Zone

Suffocatedfish

Lowdissolvedoxygen

Decreased fishpopulation

Altered food web

Thermal Pollution

Groundwater Pollution: SourcesGroundwater Pollution: Sources

Low flow rates Low flow rates Few bacteria Few bacteria

Cold temperatures Cold temperatures

Coal strip mine runoff

Pumping well

Waste lagoon

Accidental spills

Groundwater flow

Confined aquifer

Discharge

Leakage from faulty casing

Hazardous waste injection well

Pesticides

Gasoline station

Buried gasoline and solvent tank

Sewer

Cesspool septic tank

De-icing road salt

Unconfined freshwater aquifer

Confined freshwater aquifer

Water pumping well Landfill

Groundwater Pollution PreventionGroundwater Pollution Prevention

Monitoring aquifers - expensiveMonitoring aquifers - expensive

Leak detection systemsLeak detection systems

Strictly regulating hazardous waste disposal

Strictly regulating hazardous waste disposal

Protecting recharge areas- aquifer classifications

Protecting recharge areas- aquifer classifications

Ocean Pollution: dumping and oilOcean Pollution: dumping and oil

Oil SpillsOil Spills Sources: offshore wells, tankers, pipelines and

storage tanks

Sources: offshore wells, tankers, pipelines and storage tanks

Effects: death of organisms, loss of animal insulation and buoyancy, smothering

Effects: death of organisms, loss of animal insulation and buoyancy, smothering

Significant economic impacts Significant economic impacts

Short-term cleanup problems - beaches, wildlife Short-term cleanup problems - beaches, wildlife

Long-term cleanup problem - persistence (decades)

Long-term cleanup problem - persistence (decades)

Case Study: Chesapeake BayCase Study: Chesapeake Bay

Largest US estuary

Largest US estuary

Relatively shallow Relatively shallow

Slow “flushing” action to Atlantic

Slow “flushing” action to Atlantic

Major problems with dissolved O2 Major problems with dissolved O2

Solutions: Preventing and Reducing Surface Water PollutionSolutions: Preventing and Reducing Surface Water Pollution

Nonpoint SourcesNonpoint Sources Point SourcesPoint Sources

Reduce runoffReduce runoff

Buffer zone vegetation

Buffer zone vegetation

Reduce soilerosion

Reduce soilerosion

Water PollutionControl Act (1972)

Water PollutionControl Act (1972)

Clean Water Act(1977)- set effluent standards- secondary treatment

Clean Water Act(1977)- set effluent standards- secondary treatment

Technological Approach: Septic SystemsTechnological Approach: Septic Systems

Require suitable soils and maintenanceRequire suitable soils and maintenance

Technological Approach: Sewage TreatmentTechnological Approach: Sewage Treatment

Mechanical and biological treatmentMechanical and biological treatment

Technological Approach: Advanced Sewage TreatmentTechnological Approach: Advanced Sewage Treatment

Removes specific pollutantsRemoves specific pollutants

Technological Approach: Using Wetlands to Treat SewageTechnological Approach: Using Wetlands to Treat Sewage