1. 2004 Shell Creek
Watershed Study
Advisor- Mark Seier
Researchers- Amanda Gasper, Courtney
Bennett, Cody Nelsen, Melissa
Gasper, Abbie Finkral, Brittany Pieke, Katie
Dunlap, Kelly Dunlap, Sarah O’Brien, Tom
O’Brien, Kali Roundy, Laura Johnson, Cody
1
Benson, & Heather Schmidt
3. W.Q.I.
• The Water Quality Index was developed by the
National Sanitation Foundation as a standard
system to compare different bodies of water.
• To determine the WQI, a series of nine tests
were performed. These tests were: dissolved
oxygen, fecal coliform, pH, Biological Oxygen
Demand (BOD), temperature, total phosphate,
nitrates, turbidity, and total solids. We also did a
water discharge test which we use to measure
the flow of the creek in cubic feet per second.
3
4. • After the tests are completed, the WQI for each
section of the creek can be computed.
• To formulate the WQI, we first computed Q-
values.
• We multiply this number by a weighting factor,
which provides a measure of the relative
importance of each test to overall water quality.
• The water quality index ranges from zero to 100.
Zero to 25 is very bad. 25 to 50 is bad. 50 to 70
is medium. 70 to 90 is good, and 90 to 100 is
excellent.
• The bio-indicator tests weren’t part of W.Q.I., but
did give us a water quality rating.
4
6. Sample W.Q.I. Form
Weighting T o t a l
Test Results Q-value Factor
DO % sat. 0.17
Fecal Coliform col/100 mL 0.16
pH units 0.11
BOD mg/L 0.11
Temperature change in C 0.1
Total Phosphate mg/L 0.1
Nitrates mg/L 0.1
Turbidity JTU 0.08
Total Solids mg/L 0.07
Overall Water Quality Index 6___
7. Test Natural Readings Cautionary
Readings
Dissolved Oxygen % 90% or higher Below 90% unless the
waters are supersaturated
Saturation due to cultural
eutrophication.
pH 6.5-8.5 Below 6.5
Above 8.5
Nitrates 0.0-1.0 ppm Consistent readings
above 3.5 ppm
Change in The higher the change,
the worse the water
Temperature quality.
Turbidity 0-8 JTU’s Increasing trends in
turbidity measurements.
7
8. Test Natural Readings Cautionary
Readings
5 Day B.O.D The higher the difference
between the original and
the 5 day reading, the
worse the water.
Phosphates Less than 1 mg/L More than 1 mg/L
Total Solids The higher the
concentration, the
worse the water.
Fecal Coliform Over 200 colonies/100
mL of water
8
9. pH Change in Total Fecal Discharge
Water Solids Coliform cubic
Temp. mg/L Col./100 ft./sec.
Degrees mL
Celsius
May 31 Site 1 7.7 0.4 490 0 NA
Site 2 7.6 0.3 640 80 NA
Site 3 7.7 -0.2 1030 20 NA
Site 4 8 0.7 1920 0 NA
Site 5 8.5 0 9310 0 NA
June 23 Site 1 8.05 0.05 570 1050 2.71
& 24
Site 2 7.85 -0.15 390 150 1.51
Site 3 8.05 -0.2 500 300 6.02
Site 4 8.05 0.3 620 200 6.55
Site 5 8 -0.6 710 9 1125 30
10. Turbidity Dissolved Dissolved 5 Day Nitrates Phosphates
JTU’s Oxygen % Oxygen B.O.D. ppm
ppm
Saturation ppm
May 31 Site 1 200 34% 3.4 2.9 22.2 2
Site 2 360 26% 2.7 0 3.3 .82
Site 3 560 18% 1.8 0 2.2 .94
Site 4 960 12% 0.7 0 2.2 .99
Site 5 800 30% 2.9 0 12.9 .81
June Site 1 62.5 59% 5.6 1.8 10.17 1.29
23 & 24
Site 2 37.5 38.5% 3.6 1.4 5.11 .38
Site 3 45 65.5% 6 1.2 9.68 .47
Site 4 50 49.5% 4.5 0 12.57 .52
10
Site 5 140 44% 4 2.7 9.77 .59
11. pH Change in Total Fecal Discharge
Water Solids Coliform cubic
Temp. mg/L Col./100 ft./sec.
Degrees mL
Celsius
July 21 & Site 1 8 0.8 460 500 1.96
22
Site 2 7.8 1.2 415 450 1.07
Site 3 8.2 0 335 600 6.54
Site 4 7.5 0.8 310 200 6.91
Site 5 8 0.8 3215 250 20.6
August Site 1 7.9 -0.6 250 50 3.688
12 & 13
Site 2 7.75 2 250 650 0.945
Site 3 7.95 -0.2 250 400 3.108
Site 4 8.05 0.3 250 100 3.572
Site 5 8.2 0.4 850 11250 9.159
12. Turbidity Dissolved Dissolved 5 Day Nitrates Phosphates
JTU’s Oxygen % Oxygen B.O.D.
Saturation ppm
July 21 Site 1 42.5 56% 4.7 1.9 22.05 1.12
& 22
Site 2 47.5 36% 3 0 9.37 0.42
Site 3 32.5 46% 3.7 1.8 9.73 0.35
Site 4 27.5 65% 5.2 3.8 9.17 0.69
Site 5 80 87% 7.2 6.3 6.21 0.79
August Site 1 35 68% 6.65 2.5 6.16 0.58
12 & 13
Site 2 25 58% 5.7 1.6 3.08 0.53
Site 3 47.5 70% 6.75 2.6 7.61 0.38
Site 4 15 86% 8.25 3 6.53 0.13
12
Site 5 65 69.5% 6.65 2.5 11.92 0.98
13. May 31 Site 1
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 27 0.17 4.59
Fecal Col./100mL 97 0.16 15.52
Coliform
pH Units 92 0.11 10.12
B.O.D. Mg/L 67 0.11 7.37
Temp. Change in o C 92 0.10 9.20
Phosphates Mg/L 26 0.10 2.60
Nitrates Mg/L 35 0.10 3.50
Turbidity JTU 5 0.08 0.40
Total Solids Mg/L 32 0.07 2.24
13
Overall Water Quality Index 55.54(medium)
14. May 31 Site 2
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 17 0.17 2.89
Fecal Col./100mL 46 0.16 7.36
Coliform
pH Units 91 0.11 10.01
B.O.D. Mg/L 98 0.11 10.78
Temp. Change in o C 91 0.10 9.10
Phosphates Mg/L 42 0.10 4.20
Nitrates Mg/L 95 0.10 9.50
Turbidity JTU 5 0.08 0.40
Total Solids Mg/L 20 0.07 1.40
14
Overall Water Quality Index 55.64(medium)
15. May 31 Site 3
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 10 0.17 1.70
Fecal Col./100mL 62 0.16 9.92
Coliform
pH Units 92 0.11 10.12
B.O.D. Mg/L 98 0.11 10.78
Temp. Change in o C 90 0.10 9.00
Phosphates Mg/L 41 0.10 4.10
Nitrates Mg/L 92 0.10 9.20
Turbidity JTU 5 0.08 0.40
Total Solids Mg/L 20 0.07 1.40
15
Overall Water Quality Index 56.62(medium)
16. May 31 Site 4
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 8 0.17 1.36
Fecal Col./100mL 97 0.16 15.52
Coliform
pH Units 82 0.11 9.02
B.O.D. Mg/L 98 0.11 10.78
Temp. Change in o C 91 0.10 9.10
Phosphates Mg/L 41 0.10 4.10
Nitrates Mg/L 92 0.10 9.20
Turbidity JTU 5 0.08 0.40
Total Solids Mg/L 20 0.07 1.40
16
Overall Water Quality Index 60.88(medium)
17. May 31 Site 5
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 20 0.17 3.40
Fecal Col./100mL 97 0.16 15.52
Coliform
pH Units 69 0.11 7.59
B.O.D. Mg/L 98 0.11 10.78
Temp. Change in o C 92 0.10 9.20
Phosphates Mg/L 42 0.10 4.20
Nitrates Mg/L 48 0.10 4.80
Turbidity JTU 5 0.08 0.40
Total Solids Mg/L 20 0.07 1.40
17
Overall Water Quality Index 57.29(medium)
18. June 23 & 24 Site 1
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 56 0.17 9.52
Fecal Col./100mL 21 0.16 3.36
Coliform
pH Units 83 0.11 9.13
B.O.D. Mg/L 88 0.11 9.68
Temp. Change in o C 92 0.10 9.20
Phosphates Mg/L 34 0.10 3.40
Nitrates Mg/L 50 0.10 5.00
Turbidity JTU 31 0.08 2.48
Total Solids Mg/L 20 0.07 1.40
18
Overall Water Quality Index 53.17(medium)
19. June 23 & 24 Site 2
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 28 0.17 4.76
Fecal Col./100mL 40 0.16 6.40
Coliform
pH Units 90 0.11 9.90
B.O.D. Mg/L 90 0.11 9.90
Temp. Change in o C 91 0.10 9.10
Phosphates Mg/L 70 0.10 7.00
Nitrates Mg/L 61 0.10 6.10
Turbidity JTU 47 0.08 3.76
Total Solids Mg/L 48 0.07 3.36
19
Overall Water Quality Index 60.28(medium)
20. June 23 & 24 Site 3
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 65 0.17 11.05
Fecal Col./100mL 34 0.16 5.44
Coliform
pH Units 80 0.11 8.80
B.O.D. Mg/L 95 0.11 10.45
Temp. Change in o C 92 0.10 9.20
Phosphates Mg/L 61 0.10 6.10
Nitrates Mg/L 51 0.10 5.10
Turbidity JTU 41 0.08 3.28
Total Solids Mg/L 30 0.07 2.10
20
Overall Water Quality Index 61.52(medium)
21. June 23 & 24 Site 4
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 46 0.17 7.82
Fecal Col./100mL 35 0.16 5.60
Coliform
pH Units 81 0.11 8.91
B.O.D. Mg/L 100 0.11 11.00
Temp. Change in o C 91 0.10 9.10
Phosphates Mg/L 55 0.10 5.50
Nitrates Mg/L 47 0.10 4.70
Turbidity JTU 39 0.08 3.12
Total Solids Mg/L 20 0.07 1.40
21
Overall Water Quality Index 57.15(medium)
22. June 23 & 24 Site 5
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 38 0.17 6.46
Fecal Col./100mL 20 0.16 3.20
Coliform
pH Units 84 0.11 9.24
B.O.D. Mg/L 70 0.11 7.70
Temp. Change in o C 91 0.10 9.10
Phosphates Mg/L 55 0.10 5.50
Nitrates Mg/L 52 0.10 5.20
Turbidity JTU 5 0.08 0.40
Total Solids Mg/L 20 0.07 1.40
22
Overall Water Quality Index 48.2(bad)
23. July 21 & 22 Site 1
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 94 0.17 15.98
Fecal Col./100mL 27 0.16 4.32
Coliform
pH Units 84 0.11 9.24
B.O.D. Mg/L 80 0.11 8.80
Temp. Change in o C 91 0.10 9.10
Phosphates Mg/L 39 0.10 3.90
Nitrates Mg/L 35 0.10 3.50
Turbidity JTU 44 0.08 3.52
Total Solids Mg/L 38 0.07 2.66
23
Overall Water Quality Index 61.02(medium)
24. July 21 & 22 Site 2
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 25 0.17 4.25
Fecal Col./100mL 27 0.16 4.32
Coliform
pH Units 90 0.11 9.90
B.O.D. Mg/L 98 0.11 10.78
Temp. Change in o C 90 0.10 9.00
Phosphates Mg/L 70 0.10 7.00
Nitrates Mg/L 52 0.10 5.20
Turbidity JTU 40 0.08 3.20
Total Solids Mg/L 45 0.07 3.15
24
Overall Water Quality Index 56.80(medium)
25. July 21 & 22 Site 3
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 40 0.17 6.8
Fecal Col./100mL 25 0.16 4.00
Coliform
pH Units 76 0.11 8.36
B.O.D. Mg/L 90 0.11 9.90
Temp. Change in o C 94 0.10 9.40
Phosphates Mg/L 72 0.10 7.20
Nitrates Mg/L 52 0.10 5.20
Turbidity JTU 51 0.08 4.08
Total Solids Mg/L 53 0.07 3.71
25
Overall Water Quality Index 58.65(medium)
26. July 21 & 22 Site 4
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 67 0.17 11.39
Fecal Col./100mL 36 0.16 5.76
Coliform
pH Units 93 0.11 10.23
B.O.D. Mg/L 62 0.11 6.82
Temp. Change in o C 91 0.10 9.10
Phosphates Mg/L 50 0.10 5.00
Nitrates Mg/L 53 0.10 5.30
Turbidity JTU 56 0.08 4.48
Total Solids Mg/L 59 0.07 4.13
26
Overall Water Quality Index 62.21(medium)
27. July 21 & 22 Site 5
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 95 0.17 16.15
Fecal Col./100mL 30 0.16 4.80
Coliform
pH Units 83 0.11 9.13
B.O.D. Mg/L 50 0.11 5.50
Temp. Change in o C 91 0.10 9.10
Phosphates Mg/L 47 0.10 4.70
Nitrates Mg/L 60 0.10 6.00
Turbidity JTU 25 0.08 2.00
Total Solids Mg/L 20 0.07 1.40
27
Overall Water Quality Index 58.78(medium)
28. August 12 & 13 Site 1
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 71 0.17 12.07
Fecal Col./100mL 45 0.16 7.20
Coliform
pH Units 85 0.11 9.35
B.O.D. Mg/L 70 0.11 7.70
Temp. Change in o C 91 0.10 9.10
Phosphates Mg/L 57 0.10 5.70
Nitrates Mg/L 60 0.10 6.00
Turbidity JTU 48 0.08 3.84
Total Solids Mg/L 66 0.07 4.62
28
Overall Water Quality Index 65.58(medium)
29. August 12 & 13 Site 2
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 55 0.17 9.35
Fecal Col./100mL 28 0.16 4.48
Coliform
pH Units 90 0.11 9.90
B.O.D. Mg/L 90 0.11 9.90
Temp. Change in o C 86 0.10 8.60
Phosphates Mg/L 58 0.10 5.80
Nitrates Mg/L 90 0.10 9.00
Turbidity JTU 57 0.08 4.56
Total Solids Mg/L 66 0.07 4.62
29
Overall Water Quality Index 66.21(medium)
30. August 12 & 13 Site 3
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 75 0.17 12.75
Fecal Col./100mL 30 0.16 4.80
Coliform
pH Units 86 0.11 9.46
B.O.D. Mg/L 70 0.11 7.70
Temp. Change in o C 92 0.10 9.20
Phosphates Mg/L 71 0.10 7.10
Nitrates Mg/L 57 0.10 5.70
Turbidity JTU 40 0.08 3.20
Total Solids Mg/L 66 0.07 4.62
30
Overall Water Quality Index 64.53(medium)
31. August 12 & 13 Site 4
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 94 0.17 15.98
Fecal Col./100mL 50 0.16 8.00
Coliform
pH Units 81 0.11 8.91
B.O.D. Mg/L 69 0.11 7.59
Temp. Change in o C 92 0.10 9.20
Phosphates Mg/L 95 0.10 9.50
Nitrates Mg/L 60 0.10 6.00
Turbidity JTU 67 0.08 5.36
Total Solids Mg/L 66 0.07 4.62
31
Overall Water Quality Index 75.16(good)
32. August 12 & 13 Site 5
Test Results Q-Value Weighting Factor Total
D.O. % Sat. 74 0.17 12.58
Fecal Col./100mL 53 0.16 8.48
Coliform
pH Units 74 0.11 8.14
B.O.D. Mg/L 70 0.11 7.70
Temp. Change in o C 91 0.10 9.10
Phosphates Mg/L 41 0.10 4.10
Nitrates Mg/L 50 0.10 5.00
Turbidity JTU 31 0.08 2.48
Total Solids Mg/L 20 0.07 1.40
32
Overall Water Quality Index 58.98(medium)
33. 2004 Precipitation
10
9
8
7
6
Inches
5
4
3
2
1
0
May June July August
Rainfall
33
34. pH
9
Site 1
8.5
pH Level
Site 2
8 Site 3
7.5 Site 4
7 Site 5
May- June July August
31 23&24 21&22 12&13
Date
34
35. Change in Water Temperature
Degrees Celsius
2.0 August 12 & 13
1.5 May 31 June 23 & 24 July 21 & 22
1.0
0.5
0.0
-0.5
-1.0
Site 1 Site 2 Site 3
Site 4 Site 5
35
36. Total Solids
10000
8000
mg/L
6000
4000 Site 1
2000
0 Site 2
Site 3
1
2
13
6
-3
&2
&2
Site 4
&
ay
21
25
12
M
ly
st
ne
Site 5
Ju
gu
Ju
Au
Dates
36
37. Fecal Coliform
Colonies per 100 mL
1200
1000
800
600 Site 1
400
200 Site 2
0
Site 3
13
22
1
24
Site 4
-3
2&
&
&
ay
21
23
t1
Site 5
M
ly
ne
us
Ju
Ju
ug
A
Dates
37
43. 5 Day Biological Oxygen Demand
7
6
5
4 Site 1
ppm
3 Site 2
2
1 Site 3
0 Site 4
May-31 June July August
Site 5
23&24 21&22 12&13
Date
43
44. Nitrates
25
20
15 Site 1
ppm
10 Site 2
5 Site 3
0 Site 4
May-31 June July August
Site 5
23&24 21&22 12&13
Date
44
45. Phosphates
2.5
2
1.5 Site 1
ppm
1 Site 2
0.5
Site 3
0
Site 4
May-31
August
23&24
21&22
12&13
June
July Site 5
Date
45
46. Chemical Test Conclusion
• All W.Q.I. numbers were within the medium range, except
August 12 and 13-Site 4 (Good) and June 23 and 24-Site 5
(Bad)
• Best overall date: August 12 & 13
• Best overall site: Site 4
• Consistent pH readings
• Dissolved oxygen increased over the summer
• Turbidity decreased over the summer
• High precipitation amounts in May affected testing
because of increase in runoff
46
• Very high nitrate readings
47. WQI Averages by Site
Site 1 58.83
Site 2 59.73
Site 3 60.33
Site 4 63.85
Site 5 55.81
WQI Averages by Date
May 31 59.19
June 23 & 24 56.60
July 21 & 22 59.49
August 12 & 13 66.09
47
48. WQI Averages by Site
66
64
62
60
58
2003 Averages
56 2004 Averages
54
52
50
Site 1 Site 2 Site 3 Site 4 Site 5
Site 48
49. WQI Averages by Date
80
70
60
50
2003 Averages
40
2004 Averages
30
20
10
0
May June July August
Month 49
50. 2003 to 2004 Chemical Test Average
Comparisons
10
9
8
7
6
2003 Averages
5
2004 Averages
4
3
2
1
0
Discharge pH Nitate Phosphate B.O.D. Change in
Chemical Test Temp.
50
51. 2003 to 2004 Chemical Test Average
1200
Comparisons
1000
800
600 2003 Averages
2004 Averages
400
200
0
D.O. % Sat. Turbidity Fecal Coliform Total Solids
51
Chemical Test
54. Comparison Chart-2002 and 2004
20
18
16
14
12
10 Summer 2002
8 Summer 2004
6
4
2
0
Site 1 Site 2 Site 3 Site 4
54
55. Comparison Bio-Indicators
Throughout the Summer
Bio-Indicator Ratings
15
14
13
12
11
10 site 1
9 site 2
Ratings
8
7 site 3
6 site 4
5 site 5
4
3
2
1
0
June August
Month 55
56. Biological Indicators Conclusion
• Water quality improved over the summer
• Best overall date: August 12 & 13
• Best overall site: Site 3
• The results slightly declined compared to 2 yrs ago
•Bio-Indicator scale ranked the Shell Creek slightly below
the W.Q.I. rankings
•Bio-Indicators-poor to fair
•W.Q.I.-medium to good
56
71. Thank You To:
• Lower Platte North Natural Resource
District
• PrairieLand RC&D
• Nebraska Department of Environmental
Quality
• Shell Creek Watershed Improvement
Group
• Area Land Owners
71