San Luis Drain Shutoff
Simulations and
Link-Node Recalibration
Joel Herr and Katie van Werkhoven
Systech Water Resources, Inc.
San Joaquin River DO TMDL PI Meeting
May 15, 2008
Outline
• San Luis Drain Shutoff Forecast / Hindcast
• Model Validation
• Link-Node Recalibration
• Conclusion
Simulation Runs
• Forecast
– Load shifting
• Add flow and loading from off week to week before shutoff
• No net load reduction, only shift
– Do nothing forecast
• Assume flow and loading trends continue
• Hindcast
– Load shifting
• Actual event: use measured data
– Do nothing
• Use measured data except for continuous flow, load from
Mud Slough
Forecast Results: EC
Load shifting SL Drain shutoff forecast vs Do nothing forecast
Electrical Conductivity at Vernalis
800
4.0%
700
3.0%
2.0%
500
1.0%
400
0.0%
300
8/6/2007
8/5/2007
8/4/2007
8/3/2007
8/2/2007
7/30/2007
7/29/2007
7/28/2007
7/27/2007
7/26/2007
7/25/2007
7/24/2007
7/23/2007
7/22/2007
7/21/2007
7/20/2007
7/19/2007
7/18/2007
7/17/2007
0
8/1/2007
100
7/31/2007
-1.0%
Base Case
Without San Luis Drain -2.0%
% Reduction
-3.0%
200
7/16/2007
EC, s/cm
600
160
140
120
100
80
60
40
20
0
7/16/2007
7/17/2007
7/18/2007
7/19/2007
7/20/2007
7/21/2007
7/22/2007
7/23/2007
7/24/2007
7/25/2007
7/26/2007
7/27/2007
7/28/2007
7/29/2007
7/30/2007
7/31/2007
8/1/2007
8/2/2007
8/3/2007
8/4/2007
8/5/2007
8/6/2007
Phytoplankton,  g/l Chl-a
Forecast Results: Phytoplankton
Load shifting SL Drain shutoff forecast vs Do nothing forecast
Phytoplankton at Vernalis
20%
15%
10%
5%
0%
-5%
-10%
-15%
Base Case
Without San Luis Drain -20%
% Reduction
-25%
Relative Error of Input Projections
Mud
Slough
Salt
Slough
SJR @
Lander
Merced Tuolumne Stanislaus
River
River
River
Flow
0%
+55%
+30%
-21%
12%
-22%
EC
-15%
-14%
-13%
+2%
+29%
-10%
Phytoplankton
+250%
-5%
+8%
+601%
+57%
+525%
Hindcast Results: EC
Actual SL Drain shutoff event vs Do nothing hindcast
Hindcast Results: Phytoplankton
Actual SL Drain shutoff event vs Do nothing hindcast
Prediction of Flow at Vernalis
Flow at Vernalis
Prediction of EC at Vernalis
EC at Vernalis
Phytoplankton at Vernalis
Phytoplankton at Vernalis
Response at Crows Landing
Response at Vernalis
Response at Brandt Bridge
D.O. at Rough & Ready Island
• Effect on DO at RRI:
– Was minimal: ~0.01 mg/l
– Signal of decreased phytoplankton mostly
dispersed by Brandt Bridge
– Effect spread out over 2-3 weeks
• What does this mean?
– Load shifting signal does not transmit well to
DWSC
– Little effect for short-term loading reduction
What did we learn?
• Reducing Mud Slough phytoplankton load
may be effective at reducing
phytoplankton at Vernalis & Old River
• DWSC DO response is small, delayed, and
diffused over longer time period
Outline
• San Luis Drain Shutoff Forecast / Hindcast
• Model Validation
• Link-Node Recalibration
• Conclusion
Validation: Flow at Vernalis
Validation: EC at Vernalis
Validation: Phytoplankton at Vernalis
Phytoplankton Sampling
What’s up with 2007?
• Flow simulation very accurate
• Simulated EC ~20% less than observed
• Simulated Phytoplankton much less than
observed
• Model error or data error?
• Where are errors originating?
Data status for 2007
• Meteorology: complete
• Tributary inflows: mostly complete
– Merced River has missing time periods
– Los Banos Creek flow estimated
– Less data for agricultural drains
• Tributary water quality: complete
• Diversions: 2007 flow data included for 1
of 4 ID’s; estimated for the rest
Possible Sources of Model Error
• Newman Wasteway
– DMC Recirculation occurred 8/15-9/12/2007
• Salt Slough / Mud Slough / Los Banos Ck
– Monitoring stations upstream of SJR
– Phytoplankton growth may occur before
entering the SJR
• Unknown inputs not included in model
Location of EC Error
• EC is conservative:
– Calculate mass error (simulated – observed
load) at Crows Landing
– Calculate mass error at Vernalis
• EC error at Crows Landing accounts for
48% of error at Vernalis
Location of Phytoplankton Error
• Fixed phytoplankton at Crows Landing:
Simulation shows Vernalis is OK
Phytoplankton Growth
Model changes
• Mud Slough, Salt Slough, Los Banos creek
downstream of monitoring stations added
to model domain
– 20-25% phytoplankton growth before
reaching SJR
• Newman Wasteway added to model
domain, DMC recirculation of 2004 and
2007 simulated
– Operational for limited time, dilution effect
Model Changes
Outline
• San Luis Drain Shutoff Forecast / Hindcast
• Model Validation
• Link-Node Recalibration
• Conclusion
Link-Node Recalibration Goals
• Improve D.O. simulation from Old River to
Channel Point, maintain calibration at
Rough & Ready Island
• Improve phytoplankton simulation,
especially from Old River to Channel Point
• Increase ammonia from Old River to
Channel Point
Link-Node Recalibration Method
• Recalibration attempted with global
reaction rates (unsuccessful)
• Link-Node code upgraded for reaction
rates which vary by node
• Reaction rates recalibrated in two
sections: DWSC and elsewhere
Link-Node Recalibration
(Live demonstration of simulation results)
Brandt Bridge Phytoplankton
(live demonstration of Link-Node output)
Brandt Bridge Dissolved Oxygen
Garwood Bridge Phytoplankton
Garwood Bridge Dissolved Oxygen
Rough & Ready Dissolved Oxygen
What happens now?
• San Joaquin River Model Interface
(WARMF & Link-Node) will continue to be
available for download
• Updates will be available with new
projects
• Users can get technical support from
Systech:
[email protected]
925-355-1780