DSM2 Analysis of Water Level and Water Quality in the South Delta

Presented toCalifornia Water and Environmental

Modeling Forum February 26, 2007

Fingerprinting and Particle Tracking

Analysis

Background

• Concerns with water levels and low flow conditions in the South Delta in current SDIP studies

• Previously demonstrated that modified barrier operations could alleviate low water level and stagnation events

• Current investigation focuses on more stringent definition of flow concern in Old River and use of fingerprinting and visualization tools

Compliance Locations

Flow onlyFlow only

Flow / WLFlow / WL

Definition of Violations

• Water Level Violation – Daily minimum stage < 0 ft MSL

• Flow Violation – 3 day average flow – < 50 cfs in MR and GLC– < 100 cfs in OR

Plan C Gate Operations and Circulation Patterns at Low Flow (<2500 cfs)

Net Flow

Flood Flow

Ebb Flow

Revised Circulation Patterns at Low Flow, (when Plan C Ops result in flow violations)[TO 5]

Net Flow

Flood Flow

Ebb Flow

Summary of Changes to Plan C Barrier Operations

15 Min Flows South Delta July 1985

-6,000

-5,000

-4,000

-3,000

-2,000

-1,000

0

1,000

2,000

3,000

4,000

07/06/85 00:00 07/07/85 00:00 07/08/85 00:00 07/09/85 00:00

OR

and

MR

Flo

ws

(cfs

)

GLC_W_DS_BAR

MIDR_DS_BAR

OLDRT_DS_BAR

Under CH2M HILL revisions, GLC is closed to downstream flow (7/7/85) in order to shift water

to Old River and Middle River.

Standard SDIP gate operation lets flood tide enter Middle River and Old River, but does not

let ebb tide out (net flow is upstream).

Violations Summary (April to November only)

RUN Days with Water Level Violations

Low Flow Violations Total Violations

Grant Line Canal Up-stream of East Barrier (206)

Middle River at Mowry (126)

Old River at Tracy Road Bridge (71)

Grant Line Canal Down-stream of West Barrier (213)

Grant Line Canal Up-stream of East Barrier (206)

Middle River at Mowry (126)

Middle River Up-stream Barrier (133)

Old River near Tracy Up-stream of Barrier (79)

Old River at Tracy Road Bridge (71)

Step 1 (Base Line)

17 18 82 10 2 256 160 0 27 572

50 cfs OR

Trigger[TO2]

0 0 0 1 1 0 2 0 2 6

100 cfs OR

Trigger [TO5]

0 1 0 0 0 4 0 5 1 11

* In TO2, 50 cfs rule was applied even in OR

Fingerprinting Analysis

• Two planning simulations:– Temporary Barriers– CH2M HILL Modified Plan C

• Volumetric and Constituent Analysis– Volumetric Analysis provides origin of water at

any point through time on a fractional basis– Constituent Analysis provides origin of salt (EC)

at any point through time on a fractional basis

Volumetric Fingerprinting Analysis:Old River

Fingerprint at Old River near Tracy downstream of Barrier Permanent Barriers (CH)

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

O-8

7

J-88

A-8

8

J-88

O-8

8

J-89

A-8

9

J-89

O-8

9

J-90

A-9

0

J-90

O-9

0

J-91

A-9

1

J-91

Perc

ent o

f Wat

er b

y So

urce

DICU Mtz Sac SJR

Fingerprint at Old River near Tracy downstream of Barrier Temporary Barriers

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

O-8

7

J-88

A-8

8

J-88

O-8

8

J-89

A-8

9

J-89

O-8

9

J-90

A-9

0

J-90

O-9

0

J-91

A-9

1

J-91

Perc

ent o

f Wat

er b

y So

urce

DICU Mtz Sac SJR

Volumetric Fingerprinting Analysis:Middle River

Fingerprint at Middle River Downstream of BarrierTemporary Barriers

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

O-8

7

J-88

A-8

8

J-88

O-8

8

J-89

A-8

9

J-89

O-8

9

J-90

A-9

0

J-90

O-9

0

J-91

A-9

1

J-91

Perc

ent o

f Wat

er b

y So

urce

DICU Mtz Sac SJR

Fingerprint at Middle River Downstream of BarrierPermanent Barriers (CH)

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

O-8

7

J-88

A-8

8

J-88

O-8

8

J-89

A-8

9

J-89

O-8

9

J-90

A-9

0

J-90

O-9

0

J-91

A-9

1

J-91

Perc

ent o

f Wat

er b

y So

urce

DICU Mtz Sac SJR

Summary of Period-Averaged Contribution from Various Sources

Sacramento River (%)

San Joaquin River (%)

Delta Islands (%)

Location Temporary Barriers

Permanent Gates

Temporary Barriers

Permanent Gates

Temporary Barriers

Permanent Gates

MR DS Barrier 29 39 56 51 14 9

OR Tracy 21 46 67 43 12 10

GLC DS Barrier 16 21 79 71 5 7

Banks PP 58 57 32 34 8 8

Tracy PP 42 44 50 48 7 8

Summary of EC Results:DICU Influence in Middle River

Monthly Avg EC Source Comparison at Middle River DS

of the barrier

-40

-20

0

20

40

60

80

100

Oct-75 Oct-76 Oct-77 Oct-78 Oct-79 Oct-80 Oct-81 Oct-82 Oct-83 Oct-84 Oct-85 Oct-86 Oct-87 Oct-88 Oct-89 Oct-90

Date

Perc

ent E

C (%

)TempBarriers DICU

PermBarriers DICU

DICU Difference (PermBarriers - TempBarriers)

Particle Tracking Analysis

• Three simulation periods:– July/August 1985 – consistent with DWR Delta

Modeling analysis– April/May 1987 – VAMP period– June/July 1988 – Extremely low SJR, exports

• Three DSM2 Simulations:– Temporary Barriers– CH2M HILL Modified Plan C– DWR Modified Plan C – (All runs have consistent BCs with updated SJR flows)

Cumulative Flows: Old River

Old River Flows - July 1985

-400,000

-300,000

-200,000

-100,000

0

100,000

200,000

300,000

400,000

7/1/

85

7/2/

85

7/3/

85

7/4/

85

7/5/

85

7/6/

85

7/7/

85

7/8/

85

7/9/

85

7/10

/85

7/11

/85

7/12

/85

7/13

/85

7/14

/85

7/15

/85

7/16

/85

7/17

/85

7/18

/85

7/19

/85

7/20

/85

7/21

/85

7/22

/85

7/23

/85

7/24

/85

7/25

/85

7/26

/85

7/27

/85

7/28

/85

7/29

/85

7/30

/85

7/31

/85

Flow

(cfs

)Temp Barriers;Cumulative flow

SDIP; Cumulative FlowCH SDIP;Cumulative Flow

CH-SDIP Gate Changes:July 7th, 10th, 13th,

22nd, and 25th

Conclusions

• Flexible SDIP gates shown to effectively manage water level and flow

• Sacramento River influence in South Delta Channels is significantly increased with Permanent Barriers

• Particle Tracking simulations demonstrate the potential of flushing flows in Middle and Old River

• Results indicate that one-day flushing flows are not likely to traverse entire length of Middle or Old River; sustained flows are required