10. 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.
10
11. • 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.
- 0 - 25 is very bad
- 25 - 50 is bad
- 50 - 70 is medium
- 70 - 90 is good
- 90 - 100 is excellent
• The bio-indicator tests weren’t part of W.Q.I., but did
give us a water quality rating.
11
13. 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 ___
13
15. pH
8.4
8.1
Site 1
7.8 Site 2
p H Le ve l
7.5 Site 3
Site 4
7.2 Site 5
6.9 Site 6
6.6
6.3
Ma y 26 Jun e 15&16 July 9&10 Aug ust 7
Da te
15
16. Cha nge in Wa te r Te mpe ra ture
4
3
Site 1
De g re e s Ce lcius
2
Site 2
Site 3
1
Site 4
Site 5
0
Site 6
Ma y 27 Jun e 15 & July 9 & 10 Aug ust 7
-1 16
-2
Da te
The higher the change, the worse the water 16
quality.
17. Tota l Solids
2500
2000
Site 1
Site 2
1500
mg/ L
Site 3
Site 4
1000
Site 5
Site 6
500
0
Ma y 27 Jun e 15 & July 9 & 10 Aug ust 7
16
Da te
The higher the concentration, the worse the water quality.
17
19. Fe ca l Coliform
450
400
350
Site 1
colon ie s/ 100 m L
300 Site 2
250 Site 3
200 Site 4
150 Site 5
100 Site 6
50
0
Ma y 27 Jun e July 9 & 10 Aug ust 7
15&16
Da te
19
20. Flow
90
80
Cub ic fe e t p e r se con d
70
Site 1
60 Site 2
50 Site 3
40 Site 4
30 Site 5
20 Site 6
10
0
Ma y 27 Jun e 15 & July 9 & 10 Aug ust 7
16
Da te
20
21. Turbid ity
600
500
Site 1
400 Site 2
Site 3
JTU's
300
Site 4
200 Site 5
Site 6
100
0
Ma y 27 Jun e 15 & July 9 & 10 Aug ust 7
16
Da te
21
22. Dissolve d O xyge n
100
90
80
70 Site 1
% Sa tura tion
Site 2
60
Site 3
50
Site 4
40
Site 5
30
Site 6
20
10
0
Ma y 27 Jun e 15 & July 9 & 10 Aug ust 7
16
Da te
22
23. 5 Da y Biologica l O xyge n De ma n d
6
5
Site 1
4 Site 2
Site 3
ppm
3
Site 4
2 Site 5
Site 6
1
0
Ma y 27 Jun e 15 & July 9 & 10 Aug ust 7
16
Da te
The higher the change, the worse the water 23
quality.
24. N itra te s
40
35
30 Site 1
25 Site 2
Site 3
ppm
20
Site 4
15 Site 5
10 Site 6
5
0
Ma y 27 Jun e 15 & July 9 & 10 Aug ust 7
16
Da te
24
25. Phospha te s
3.5
3
2.5 Site 1
Site 2
2 Site 3
ppm
1.5 Site 4
Site 5
1 Site 6
0.5
0
Ma y 27 Jun e 15 & July 9 & 10 Aug ust 7
16
Da te
25
26. Chemical Test Conclusion
• Significant increase in stream discharge
• Increasing nitrate levels
• DO consistently low
• Total dissolved solids increasing
26
27. WQI Averages by Site
Good
70
65
60 Medium
WQI
55
50
Bad
45
Site 1 Site 2 Site 3 Site 4 Site 6 Site 5
2003 Averages 2004 Averages 2005 Averages
2006 Averages 2007 Averages
27
28. WQI Averages by Date
Good
70
65
60 Medium
WQI
55
50
Bad
45
May June July August
Month
2003 Averages 2004 Averages 2005 Averages
2006 Averages 2007 Averages
28
29. 2003 to 2007 Chemical Test Average
Comparisons
18
16
14
12
2003 Averages
10
2004 Averages
8
2005 Averages
6
2006 Averages
4
2 2007 Averages
0
pH
.
es
e
es
.D
p.
g
at
.O
at
ar
m
itr
ph
Te
ch
B
N
os
is
in
D
Ph
e
ng
ha
Chemical Test
C
29
30. 2003 to 2007 Chemical Test Average Comparisons
1200
*2006 Fecal Coliform
1000 Average 8,058 col/100 mL
800
2003 Averages
2004 Averages
600
2005 Averages
400 2006 Averages
2007 Averages
200
0
D.O. % Sat. Turbidity Fecal Coliform Total Solids
30
Chemical Test
33. Bio-Indicator Ratings
12 site 1
site 2
10
site 3
8
site 4
Ratings
6 site 5
4 site 6
2
0
May June July August
Month
33
34. Fa the a d Minnow
18
16
Fish Study Sa nd Shine r
Re d Shine r
Rive r Shine r
Bla ck Bullhe a d
14
Avera ge N um ber of Fish
Ye llow Bullhe a d
G re e n Sunfish
12
Ca rp
10
8
6
4
2
0
Site 1 Site 2 Site 3 Site 4 Site 6 Site 5
58.51 58.28 61.06 50.4 55.24 47.0
WQI 34
WQI WQI WQI WQI WQI
36. 2007 Flood Study
Date Avg. Total NO3 Solid Solid
Width Flow Fecal Solids
and Depth Discharge Discharge
(ft) (cfs) Coliform (ppm)
Time (ft) (mg/L) (lbs/min) (tons/hr)
5/30
3:08 110 8.42 2243 200 9300 0 78145 2344
AM
5/30
8:00 84 7.38 1451 0 5160 2.31 27876 836
AM
X cu ft 60 sec 28.32 L X mg 1g 1 lb 1 ton 60 min
1 sec 1 min 1 cu ft 1L 100 mg 453.6 g 2000 lb 1 hr
36
40. Website
• http://newman.esu8.org/project.html
OR
• http://newman.esu8.org/
• Click “Our Students”
• Click “Student Projects”
• Click “Watershed Project”
• You can see our data and further
information concerning this project,
including pictures. 40
42. Thank You To:
• Lower Platte North Natural
Resource District
• PrairieLand RC&D
• Natural Resource Conservation
Service
• Nebraska Department of
Environmental Quality
• Shell Creek Watershed 42
Improvement Group