1. Biological Oxygen Demand (BOD)
Jonathan Betz-Zall
Highline Community College
May, 2010

2. Definition
The amount of oxygen required by aerobic microorganisms to decompose the organic matter in a sample of water, such as that polluted by sewage. It is used as a measure of the degree of water pollution. Also called biochemical oxygen demand. Source: The American Heritage® Dictionary of the English Language

3. Causes

4. Excess Phosphorus

5. Another source:

6. Algal Bloom

7. Aerobic Bacteria

8. Untreated domestic sewage BOD ~350 ppm

9. Waste water from breweries BOD~550 ppm

10. Waste water from petroleum refineries BOD~850 ppm

11. Abattoir wastes BOD~2,600 ppm

12. Pulpmill wastes BOD~25,000 ppm

13. BOD Across the World

14. Sewage System

15. Greywater System
1. Grey water tank for biological treatment (900 litres) 2. Grey water inflow 3. Grey water overflow 4. Sewage system 5. Grey water system ventilation 6. Ultrafiltration module / sterilisation 7. Fresh water inflow 8. Rainwater / fresh water tank 2400 liters 9. Ventilation unit 10. Domestic water supply 11. Submersible pump 12. Biovitor 13. Rainwater inflow 14. Drinking water feed 15. System control 16. Soak-away 17. Rainwater / fresh water overflow 18. Soak-away ventilation

16. Our Area:

17. Google Earth Image