1. EPA Report to Congress 2000 (latest available on web) Provided to Dr.G. Powell by Dr. D. Monreau, NCSU for this website

2. Uses for which assessments were made Aquatic life support Fish consumption Primary contact recreation (swimming) Secondary contact recreation Drinking water supply Agricultural

3. Rivers and Streams

4. Rivers and Streams

5. Lakes, Ponds, and Reservoirs

7. Estuarine Waters

10. Oxygen Balance in Streams Balance between Supply and Demand

11. Oxygen Supply

12. Oxygen Resources of Streams Atmosphere Water Oxygen O 2 Conc. Saturation ( equilibrium)

13. 86 77 68 59 50 41 32 oFoF

14. Water Quality Standard = 5 mg/l

15. Oxygen Demand

16. Water

17. Biological Oxidation of Organic Matter Carbohydrate Oxidation: C x H y O z + O 2 bacteria CO 2 + H 2 O Algal cell oxidation: (CH 2 O) 106 (NH 3 ) 16 H 3 PO 4 + 1.2 O 2 bacteria CO 2 + H 2 O Algae = 34.3% C; 7.1% H; 51.8% O; 6.0% N; 0.8% P (15 lb algae/lb N)

18. Nitrogen Cycle Animal protein Organic N Plant protein Organic N Ammonia NH 3 and NH 4 + Nitrites NO 2 - Nitrates NO 3 - Atmospheric N 2 Waste material, death & decay decay O2O2 O2O2 Anaerobic (O 2 absent) Aerobic (O 2 present) lightning nitrogen-fixing bacteria Hydrolysis is a chemical decomposition process that uses water to split chemical bonds of substances. hydrolysis

19. The Oxygen Sag- Net Effect of Supply and Demand

20. Saturation Concentration

22. Nutrients

24. 1 lb N 16.7 lb algae 1.2 lb O 2 /lb algae 20 lb O 2 /lb N Approximate chemical formula for algal cells: (CH 2 O) 106 (NH 3 ) 16 H 3 PO 4 C= 34.3% H = 7.1% O = 51.8% N = 6.0% P = 0.8% respiration synthesis At 0.0015 lb NH 3 /day/person (0.00124 lb N/day/person), oxygen demand associated with algal growth = 0.025 lb/day/person Generally exerted in lakes or estuaries where reaeration is low.

25. Approximately 160 river miles

26. Nutrient Loads in Neuse River Basin by Source

27. Load = point +export from land = 21.8 million tons/yr = 5.5 lb/ac/yr

28. Load = point + export from land = 2.35 million lbs/yr = 0.59 lb/ac/yr = 0.45 million lbs

29. Chesapeake Bay Watershed Maryland Delaware New York District of Columbia Virginia West Virginia Pennsylvania Susquehanna James Potomac Appox. 160 mi.

30. Threats to the Bay and Rivers N UTRIENTS S EDIMENTS T OXIC CHEMICALS H ABITAT LOSS O VERFISHING

31. Estimated 1985 Base Nutrient Loads

32. Total = 303 million lbs/yr DHM

33. Total = 23.8 million lbs/yr DHM

34. Water Pollutant Loads

35. (Mass Loadings)

36. Nonpoint Source Loads of Nitrogen in the United States

37. Input to fields Export to streams Delivery to estuaries Decay

38. INPUTS 1 ton/ac = 3.125 lb/ac. Applied Nitrogen Loads From Commercial Fertilizer Lbs/ac <3.1 3.1-6.3 6.3-12.5 12.5-21.9 >21.9

39. Applied Nitrogen Loads From Animal Manure INPUTS 1 ton/sq.mi. = 3.125 lbs/ac Lbs/ac <3.1 3.1-6.3 6.3-12.5 12.5-21.9 >21.9

40. INPUTS 1 ton/sq.mi. = 3.125 lb/ac Nitrogen Loads From Atmospheric Deposition Lbs/ac <3.1 3.1-4.1 4.1-5.3 5.3-6.3 >6.3

41. March, 2000 water.usgs.gov/nawqa/

42. Nitrogen Export by Region

43. 10 8 6 4 2 Lb/ac 1 kg/ha = 0.89 lb/ac 1 lb/ac = 1.12 kg/ha

44. Phosphorous Export by Region

45. 0.9 0.7 0.5 0.3 0.1 lb/ac