1. Objectives:  Describe the types, sources, and effects of freshwater pollutants.  Evaluate the solutions to reduce and prevent water pollution.

2. Question:  How “clean” is the big Sioux?

3. Stream Pollution  Flow increases stream recovery  Flow reduction and overload

4. Oxygen Sag Curve  Factors influencing recovery Fig. 19-5 p. 488

5. Click to view animation. Stream Pollution Stream pollution animation.

6. Pollution of Lakes  Stratification  Little flow  Small volume  Biomagnification

7. Cultural Eutrophication  Eutrophication – nutrient enrichment  Nitrate and Phosphate effluents  Algae bloom → death → decomposition  High BOD = low DO

8. Pollution of Lakes Fig. 19-7 p. 491

9. Lake Pollution Solutions  Prevention: water treatment, ban/limit phosphates, soil conservation  Cleanup: removing/controlling plants, aeration

10. Groundwater Pollution  Low flow rates  Few bacteria  Cold temperatures Fig. 19-10 p. 494 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  High-risk human health problem

11. Groundwater Pollution Prevention  Monitoring aquifers  Leak detection systems  Strictly regulating hazardous waste disposal  Storing hazardous materials above ground  Cleanup?

12. Better Ask Somebody Survey says...

13. Better Ask Somebody Survey says...

14. Objectives:  Describe the types, sources, and effects of freshwater pollutants.  Evaluate the solutions to reduce and prevent water pollution.