Suzan Tahir

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Department of Civil Environmental
EngineeringUniversity of Utah
Sediment Oxygen Demand Nutrient Flux Studies in
Jordan River
Dr. Ramesh Goel Assistant Professor Civil
Environmental Engineering University of Utah
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CONCEPT ON SEDIMENT OXYGEN DEMAND (SOD)
Water
O2
Nutrients
Sediments
Organics etc
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SEDIMENT OXYGEN DEMAND
SOD is a combination of all of the
oxygen-consuming processes that occur at or just
below the sediment-water interface.
Most of the SOD at the surface of the sediment is
due to the biological decomposition of organic
material and the microbially facilitated
nitrification of ammonia
SOD several centimeters into the sediment is
often dominated by the chemical oxidation
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How to Measure SOD?
DOT Sediments Water column
DOW Water column only
SOD DOT DOW
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Methodology
Schematic of SOD Chamber
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CONTROL
ANALYSIS
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(No Transcript)
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SOD Rate Estimation

Equation used for the SOD rate
SOD t sediment oxygen demand rate (g/m2d) b
slope of the oxygen-depletion curve (mg/L-min) V
the volume of the chamber (L) A the area of
bottom sediment covered by the chamber
(m2) 1.44 units-conversion constants
SOD20 the rate at 20C t in C
Source Parkhill and Gulliver, 1997
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SOD- 2300S site
Initial linear data is used
Slope of SOD 1 0.0065 mg/L-min Slope of Control
0.0005 mg/L-min Net SOD 0.0065-0.0005 0.0060
0.006 1.44 240 2.073 g/m2-day
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SOD Rates
Location Coordinates Temperature (0 C) SOD rate (g/m2-day) SOD20oC (g/m2-day)
980 S, 900 W (Peace Gardens) 19.78 7.56 7.66
280 N, 1460 W 22.27 1.93 1.67
4800 S, 580 W 19.83 2.18 3.77
Legacy Nature Preserve 22.13 3.9 2.89
9000 S ,900 W 16.02 1.54 1.20
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Difficulties

• Bed-sediment heterogeneities
• Measurement errors
• Possible disturbances during chamber placements
• Sampling errors
• Control chamber data fluctuations

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Acknowledgements

• Mr. James Harris, Utah Department of Water
  Quality
• Mr. Carl Adam- Utah DWQ
• Leland Myers- Great inspiration
• The whole water quality personnel

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Thank You!!!
Questions???