1. Development of a HAB Model for the James River Estuary
Chesapeake Modeling Symposium
Williamsburg, VA
Jim Fitzpatrick1, Nataliya Kogan1, Jian Shen2,
Nikolai Gurdian3, and Dave Jasinki4,
1-HDR VIMS TetraTech CEC
Mixed consultant/academic team

2. Project Goals Develop a site specific James River water quality model
Re-assess attainability of chl-a criteria
Revisit the James River TMDL allocations
Chl-a WQS are now based on season (spring/summer) and salinity regime

3. Project Approach Development of Multiple Models Deterministic Models
Linked watershed, hydrodynamic and conventional eutrophication and HAB models
Eutrophication Model
Nutrient loads
Watershed Model
Hydrodynamic Model QF
QT, S, T
HAB Model
Deterministic modeling system consists of a watershed model (similar to HSPF), a hydrodynamic model (EFDC), and a conventional eutrophication model (EFDC’s HEM3) and a HAB model (RCA)
Nutrient loads

4. Model Framework Watershed, Hydrodynamic and Eutrophication Models
Watershed Model (LSPC)
James River watershed and James River hydro/WQ model grid
Hydrodynamic Model (EFDC)

5. Model Framework Watershed, Hydrodynamic and Eutrophication Models
Water quality models
Nutrients, phytoplankton, dissolved oxygen
Sediment nutrient diagenesis/flux submodel
Microphytobenthos submodel
Conventional eutrophication model (HEM-3D)
3 algal species: diatoms, greens, cyanobacteria
HAB model (RCA)
6 algal species:
3 freshwater: diatoms, greens, Microcystis
3 marine: diatoms, mixed, Cochlodinium
HAM model has algal physiology built in: Microcystis-vertical buoyancy, Cochlodinium-vertical swimming and use of labile DON

6. Model Calibration Watershed Model
Sample calibration of watershed model
James River at Richmond, VA ( )

7. Model Calibration Hydrodynamic Model Sample calibration of hydro model
Currents
Tidal Elevation
Sample calibration of hydro model

8. Model Calibration Conventional Eutrophication Model
Sample calib results from standard eutrophication model for freshwater segment TF5.5

9. HAB Model Framework Freshwater and marine species – salinity impacts
HAM model has algal physiology built in: Microcystis-vertical buoyancy, Cochlodinium-vertical swimming and use of labile DON

10. HAB Model Framework Freshwater and marine species – salinity impacts
HAB species controlled by temperature, light and nutrients
HAM model has algal physiology built in: Microcystis-vertical buoyancy, Cochlodinium-vertical swimming and use of labile DON

11. HAB Model Framework Freshwater and marine species – salinity impacts
HAB species controlled by temperature, light and nutrients
HAB species permitted to have vertical movement (buoyancy or swimming) to optimize access to light or nutrients
HAB species also subject to reduced grazing pressure
Cochlodinium permitted to access “labile” organic nitrogen
Evaluated model sensitivity to HAB release from sediment vs. low threshold background value
HAM model has algal physiology built in: Microcystis-vertical buoyancy, Cochlodinium-vertical swimming and use of labile DON

12. Model Calibration HAB Model
Calibration results from HAB model showing chl-a, algal carbon and algal species for station TF5.5

13. Model Calibration HAB Model
Repeating species model computations and comparing to long term average data for TF5.5
Egerton and Marshall, 2014

14. Model Calibration HAB Model RET5.2
Repeating species model computations and comparing to long term average data for TF5.5

15. Model Calibration
RET5.2
Repeating species model computations and comparing to long term average data for TF5.5

16. Model Calibration HAB Model
DataFlow cruises suggest that Cochlodinium blooms initially develop in the Lafayette River and then spread into the Elizabeth River and finally into the poly- and mesohaline James River
DataFlow fluoresence (chl-a) data - First week of June to first week of August
VECOS DataFlow, June-August 2012

17. Model Calibration HAB Model June 3, 2012 June 13, 2012 June 23, 2012
July 3, 2012
July 13, 2012
July 23, 2012
August 2, 2012
August 12, 2012
Model computed chl-a data - First week of June to first week of August – bloom initiation in Lafayette River then to Elizabeth River then to James River estuary

18. Sediment Flux/Microphytobenthos

19. Sediment Flux/Microphytobenthos
Type of model skill assessment that was performed

20. Model Calibration Skill Assessment
Type of model skill assessment that was performed

21. Scenarios
2010 TMDL: the nutrient load reductions required to meet Chlorophyll-a criteria in the James River as estimated by the USEPA Chesapeake Bay Program Office (CBPO)
Chesapeake Bay DO Attainment: the nutrient load allocation/reductions in the James River watershed required to meet DO criteria in the Chesapeake Bay
2009 Progress TMDL Scenario: similar to the 2010 TMDL, but based on nutrient and sediment load reductions estimated to be realized through 2009
HRSD WWTP Scenario: nutrient load reductions, as part of the HRSD watershed general permit load reduction, and agreed to by HRSD as part of the state of Virginia's WIP
Scenario
Carbon
Nitrogen
Phosphorus
106 lb/year
% Reduction
Baseline
78.4 -
21.2
2.49
2010 TMDL
78.5
0.1(1)
13.0
38.7
1.61
35.3
DO Attainment
15.4
27.4
1.51
39.4
2009 Progress
15.1
28.8
1.75
29.7
HRSD
78.7
0.4(1)
20.6
2.8
2.53
1.6(1)
Scenario loadings
(1) % increase from baseline

22. Scenarios
Adjustment to downstream boundary

23. Scenarios Station 2010 TMDL DO Attainment 2009 Progress TMDL HRSD WWTP
Station
2010 TMDL
DO Attainment
2009
Progress TMDL
HRSD WWTP
TF5.2
1.0
1.5
1.3
0.1
TF5.2A
18.9
19.6
4.2
TF5.3
25.5
35.6
14.5
0.2
TF5.4
42.3
34.5
31.3
0.5
TF5.5
40.8
36.0
30.2
0.3
TF5.5A
45.8
38.5
34.3
TF5.6
51.3
42.7
39.6
1.1
RET5.2
41.6
41.7
LE5.1
54.7
42.2
2.6
LE5.2
54.2
33.8
41.2
LE5.3
54.5
27.9
40.1
1.4
LE5.4
55.4
23.5
39.8
2.3
LE5.5W
56.5
20.4
40.0
4.0
LE5.6
54.0
25.9
39.1
5.3
LFB01
51.0
24.1
37.4
10.4
We had hoped to provide some management scenario results, but project delays prevented us from getting those ready in time for the conference – models are too optimistic.

24. Acknowledgements VADEQ – Arthur Butt and John Kennedy
Rico Wang and Harry Wang (VIMS)
Paul Bukaveckas, Todd Egerton, Margie Mulholland, KC Filippino, Hans Paerl and Iris Anderson
We had hoped to provide some management scenario results, but project delays prevented us from getting those ready in time for the conference – models are too optimistic.

25. Thanks ---Questions ?