Watershed Water Quality Modeling Technical Support Center Dissolved

Watershed & Water Quality Modeling Technical Support Center Dissolved Oxygen Processes and Equations Implemented in WASP 7 Eutrophication Module WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Eutrophication - DO Interactions WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center DO Balance Processes Death Detritus Dissolution Phytoplankton CBOD 1 Periphyton Photosynthesis and Respiration Organic Decay Dissolved Oxygen CBOD 2 Sediment Oxygen Demand CBOD 3 WASP 7 Course Reaereation

Watershed & Water Quality Modeling Technical Support Center Streeter-Phelps with SOD Reaeration CO 2 DO BOD 1 Carbonaceous Deoxygenation Sediment Oxygen Demand Sediment WASP 7 Course Settling and Deposition of Organic Matter

Watershed & Water Quality Modeling Technical Support Center User Specifies Sources Boundaries & Loads Sinks User Specifies Fraction * Detritus Dissolution Phytoplankton Death * Carbon Content Periphyton Death * Carbon Content CBOD 1 Detritus CBOD 2 CBOD 3 Model Calculated Dissolution = Dissolution Rate * Theta ** Temp – 20 ° WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Sources & Sinks WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center BOD in WASP • Best to convert BOD to Ultimate BOD Values • Three BOD Classes – Fast, Medium, Slow (Labile to Refractory) – Biotic (Algae/Benthic Algae), Abiotic, WWTP – Varying Decay, F Ratios based on Sources WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center BOD 1 BOD Decay * Theta ** T-20 Boundaries & Loads Phytoplankton Death * Carbon Content BOD 2 Periphyton Death * Carbon Content BOD 3 WASP 7 Course DO

Watershed & Water Quality Modeling Technical Support Center CBOD WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Model Parameters for BOD WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Sediment Oxygen Demand WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Simulated SOD WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Reaeration WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Reaeration Options • • • Global Reaeration Segment Specific Reaeration This Sets for Segment User Defined Specify Dam. Rate Characteristics – User Selections • Covar’s Method This options Setting User sets Specifies tothe Zero rate which WASP for the Equation Selects whole network • Dam Reaeration WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Reaeration Options • Rivers & Streams – O’Connor-Dobbins – Churchill U (mps) H (m) Ka (per day) – Owens WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Reaeration Coefficients WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Dam Reaeration Where: r = ratio of deficit above and below the dam H = difference in water elevation (meters) T = water temperature (°C) a = water quality coefficient b = dam-type coefficient (Chapra, 1997) WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Dam Reaeration Water Quality Coefficient Dam Type Coefficients Polluted State A Dam Type b Gross 0. 65 Flat broad-crested regular step 0. 70 Moderate 1. 0 Flat broad-crested irregular step 0. 80 Slight 1. 6 Flat broad-crested vertical face 0. 60 Clean 1. 8 Flat broad-crested straight-slope face 0. 75 Flat broad-crested curved face 0. 45 Round broad-crested curved face 0. 75 Sharp-crested straight slope face 1. 00 Sharp crested vertical face 0. 80 Sluice gates 0. 05 WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Wind Driven Reaeration Jour. of Env Eng, Vol. 109, NO. 3, PP. 731 -752, June 1983, Author: D. J. O'Connor, TITLE: "Wind Effects on Gas- Liquid Transfer Coefficients" Wind Speed m/sec (Time Function) 10 Meters Above Water Surface Air Temperature °C (Time Function) KAWind Water Temperature °C (Segment Parameter and/or Time Function) Simulated by Hydrodynamic Model WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Modified Streeter-Phelps Reaeration CO 2 NO 3 DO NBOD 2 Settling Nitrogenous Deoxygenation CBOD 1 Carbonaceous Deoxygenation Settling Sediment Oxygen Sediment Demand 1 use WASP 7 Course BOD 1; 2 use BOD 2

Watershed & Water Quality Modeling Technical Support Center Nitrogenous BOD WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Modified Streeter-Phelps Input WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Temperature Dependency Where: KT The value of variable at the local temperature, T (°C) The value of the variable at 20 °C Ө The empirical constant for each temperature dependent system variable, user specified WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Linear DO Balance Reaeration NO 3 CO 2 Mineralization Org-N NH 3 DO BOD 1 Nitrification Carbonaceous Deoxygenation Phyto Settling Photosynthesis Respiration Sediment Oxygen Demand WASP 7 Course Settling

Watershed & Water Quality Modeling Technical Support Center Linear DO Balance Input WASP 7 Course

Watershed & Water Quality Modeling Technical Support Center Measuring Photosynthesis & Respiration WASP 7 Course