Review of DWSC Modeling- what should we do next?

Russ Brown, Jones & Stokes

DO-TMDL Technical Work Group May 16,2006

DO Modeling Ingredients

• Temperature (& DO saturation)

• Geometry (area, depth, width)

• Flow (cfs) and Travel Time (or distance)

• BOD: CBOD, NBOD, SOD, Detritus

• Algae: N/P/light/C-photosynthesis-pH

• Reaeration f(wind)/O2 injection

Calibration of DO Models

• Matching seasonal DO does not validate assumptions about model relationships, rates, responses, and inputs

• CBOD decay f(temperature,settling)• SOD f(temperature, settling)• NBOD f(temperature, nitrifying bacteria)• Algae f(temperature,N,P, light,settling)• Detritus f(algae decay, settling)

Purposes for DWSC DO Models

• Basic Understanding of DWSC Processes

• Evaluate flow and algae inflow effects

• Determine TMDL responsibility & credits

• Determine effects of management actions– Evaluate wastewater permit limits– Mitigation for DWSC deepening– Evaluate performance of oxygenation

DWSC Models Galore!!

• RMA 1-D link-node

• City of Stockton 1-D link-node

• DSM2-QUAL 1-D Lagrangian Transport

• HydroQual 3-D with sediment fluxes

• USGS/UC Davis/Stanford 3-D Hydro+WQ

• Statistical long-term relationships: DO=f( )

• RWQCB strawman report: Streeter-Phelps

Review of DWSC DO Models-Corps of Engineers-RMA1988

• RMA Delta tidal hydraulic model for flows• RMA link-node WQ model with Algae

(N/P/light), Detritus, CBOD, Ammonia, SOD, temperature, DO

• 15 1-mile CSTR segments;1 month simulations for 7 years; time-series and longitudinal plots

• Sensitivity of inputs and coefficients; deepening• WQ model suggested mitigation of 2,500 lb/day

(0.2 mg/l) for deepening from 30 to 35 feet

Review of DWSC DO Models-City of Stockton-Systech 1993

• Systech link-node tidal hydraulic and WQ• Algae (N/P/light), detritus, CBOD, ammonia,

SOD, temperature, DO• 23 segments from HOR to Turner Cut; July 90-

Dec 91 calibration; time-series and long plots• Verified for 1993, 1996; CALFED improvements

(pheophytin, re-suspension) for 1999, 2000, and 2001

• Used to evaluate effects of flows, wastewater loads (ammonia), and aeration in DWSC

Review of DWSC DO Models- DSM2-QUAL- DWR 2001

• DSM2-QUAL model based on 1995 PhD Thesis of Hari Rajbhandari

• Algae (N/P/light), CBOD, ammonia, SOD, temperature, DO

• DSM2-HYDRO Delta grid; 25 segments from HOR to Turner Cut; 1998-1999 calibration; 1996-2000 validation; time-series plots of Temp & DO

• 1976-1991 DSM2 planning studies can use selected river inputs from 1997-2001 for SJR

Review of DWSC DO Models-ECOMSED/RCA- HydroQual 2006

• HydroQual model based on 3-D ECOMSED/RCA with sediment flux

• Algae (N/P/light), CBOD, detritus, ammonia, sediment nutrient flux/SOD, temperature, DO

• DSM2-Delta results for tidal stage & flow; 25 segments from HOR to Turner Cut; 3 lateral sections with 10 layers; 2000-2001 calibration; time series plots of stage, flow, and water quality parameters at various stations (top and bottom)

Review of DWSC DO Models-USGS,UC Davis,Stanford-2007

• 20-m 3-D Hydrodynamics by Pete Smith,USGS; 1-m layers (800,000)

• Tidal flows and temperature stratification, DO model using 3-D results to be developed by UC Davis

• Three 1-month intensive hydrodynamic and water quality surveys throughout DWSC by UC Davis and Stanford; August 2004, August 2005; August 2006?

DWSC Data Atlas

• 1984-2005 daily flow, EC, pH, T, SS, DO

• RWCF effluent concentrations

• Provide comparisons between years

• Show patterns of flow, EC, DO, and algae

• Identify basic relationships for DWSC

• Provide model inputs and calibration data

DO Deficit and DWSC Flows in 2004

0

1,000

2,000

3,000

4,000

5,000

6,000

1-Jan 1-Feb 1-Mar 1-Apr 1-May 1-Jun 1-Jul 1-Aug 1-Sep 1-Oct 1-Nov 1-Dec

Flo

w (

cfs

)

0

1

2

3

4

5

6

7

8

9

10

11

12

Exp

ort

s/V

ern

alis R

ati

o

Measured Flow Estimated Flow Vernalis Flow Exports/Vernalis

Stockton Flow as a Fraction of Vernalis Flow in 2004

-0.25

0.00

0.25

0.50

0.75

1.00

1.25

0 3 6 9 12 15

Exports/Vernalis Ratio

Sto

ckto

n/V

ern

alis

Rat

io

Measured Estimated

Measured Stockton flow data is very important, and difficult to estimate or model accurately

DO in the San Joaquin River at Mossdale, 2004

0

2

4

6

8

10

12

14

16

18

20

1-Jan 1-Feb 1-Mar 1-Apr 1-May 1-Jun 1-Jul 1-Aug 1-Sep 1-Oct 1-Nov 1-Dec

Dis

solv

ed O

xyge

n (m

g/L)

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

Vern

alis

Flo

w (c

fs)

Min DO Max DO Saturated DO Vernalis Flow

DO at Mossdale is usually saturated or supersaturated in summer-can we estimate algae biomass from diurnal DO and pH?

Algae in San Joaquin River at Mossdale, 2004

0

50

100

150

200

250

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan

Co

nce

ntr

atio

n (

m g/L

)

0

1000

2000

3000

4000

5000

Flo

w (

cfs)

Chlorophyl a Pheophytin Algae Pigment SJR Flow Vernalis

How will the DWSC respond to SJR flow and algae? What else would you like to know about to make a better prediction of DWSC DO?

DO in the Stockton DWSC at Rough and Ready Island, 2004

0

2

4

6

8

10

12

1-Jan 1-Feb 1-Mar 1-Apr 1-May 1-Jun 1-Jul 1-Aug 1-Sep 1-Oct 1-Nov 1-Dec

Dis

solv

ed O

xyg

en (

mg

/L)

0

500

1,000

1,500

2,000

2,500

3,000

Min DO Max DO Saturated DO DO Objective Stockton Flow

DWSC DO is often lowest during winter and summer low flows

DO Saturation Deficit in the Stockton DWSC vs. Flow, 2004

0

2

4

6

8

10

12

-500 0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000

DO

Satu

rati

on

or

DO

Defi

cit

(m

g/L

)

Saturation Deficit Saturation

DO Deficit in the DWSC appears to decrease at higher flows

DO in the Stockton DWSC vs. Flow,

0

2

4

6

8

10

12

-500 0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000

Dis

so

lved

Oxyg

en

(m

g/L

)

Min DO Stockton Flow

DWSC Modeling of Flow, Stratification, Turbidity, Algae and DO

• There should be more direct interaction between data collection efforts and modeling integration and interpretation

• All potential controls of flow and sediments and nutrients and algae on the SJR and DO in the DWSC should be integrated and adaptively managed by a team

Observed DO Conditions at Mossdale and RRI

Tidal Model of DWSC

Calibrate & Revise

Sensitivity Results

Implement Management Actions

Comparative Results

Natural Environmental Conditions

Adaptive Management of the DWSC

Suggested Future DWSC Modeling Efforts

• Estimate daily inputs needed for DWSC

• Historic simulations of 1984-2005 (RRI)

• Update inputs & simulation for each year

• Sensitivity of stratification and DO to wind, sun, tides, and flow

• Determine algal dynamics (movement, photosynthesis, respiration) in the DWSC

Suggested Future DWSC Modeling Efforts

• Effects of increased flow (with algae)

• Effects of RWCF ammonia on algae & DO

• Effects of aeration and oxygen injection

• Forecast DWSC DO for the next week

• Your best idea goes here

• Your other ideas go here