developing flow prescriptions for the sacramento-san ... · (fleenor et al. 2010 paper) steps: 1)...

1

Developing Flow Prescriptions Developing Flow Prescriptions for thefor the

SacramentoSacramento--San Joaquin DeltaSan Joaquin DeltaWilliam E. FleenorWilliam A. Bennett

Peter B. MoyleJay R. Lund

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Hydrologic and Ecosystem LinksHydrologic and Ecosystem Links

� Flow Regime is a Major Determinant of Physical Habitat

� Species Life Histories Strategies Responded to Natural Flow Variations

� Habitat Connectivity is Essential to Many Species

� Invasive Species are Promoted by Flow Alterations

� Bunn and Arthington 2002

3

Approaches for Setting Flow Criteria in the Delta

• Unimpaired Flows (1921-2003)• Historical Flows when fish were

‘doing better’ (1949-1968)• Statistical relationships between

flow and native species abundance• Accumulated Functional Flows

based on recent scientific literature

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Unimpaired Flows (1921-2003)

• Not historical ‘natural’ flows into the Delta– More rain and less snow today, with earlier

snow melt– Upstream floodplains no longer attenuate

flows– Groundwater base-flow has changed– Delta is channelized with little marsh or

floodplain

5

Water Year Comparison

0

5

10

15

20

25

30

35

40

Wet AN BN D C

% O

ccur

ance

Dur

ing

Per

iod

1921-2003 Unimpaired

1949-1968 Historical


6


0

5

10

15

20

25

30

35

40

Wet AN BN D C

% O

ccur

ance

Dur

ing

Per

iod




7


0

5

10

15

20

25

30

35

40

Wet AN BN D C

% O

ccur

ance

Dur

ing

Per

iod




8

Major Inflows to Delta(yearly average flows in maf/mo)

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

10 11 12 1 2 3 4 5 6 7 8 9

Sacramento River

0.00

0.25

0.50

0.75

1.00

1.25

1.50

1.75

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

1921-2003 Unimpaired1949-1968 Historical1986-2005 Historical

San Joaquin River

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Exports from Delta (maf/yr)

0

1

2

3

4

5

6

7

1956

1959

1962

1965

1968

1971

1974

1977

1980

1983

1986

1989

1992

1995

1998

2001

2004

2007

Mill

ion

Acr

e-Fe

et

SWP

CVP

1.4 maf

5.1 maf

10

Available Water Use (annual flows in maf/yr)

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Data courtesy of TNC

11

Statistical Relationships

0%

20%

40%

60%

80%

100%

40 50 60 70 80 90 100 110X2 Distance from Golden Gate Bridge (km)

Per

cent

Exc

eede

nce

of X

2 Lo

catio

n




A

B

C

CQ MZ CH CO EM RV

12

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

-12000 -8000 -4000 0 4000 8000 12000 16000 20000 24000 28000

Per

cent

Exc

eede

nce

of F

low 1925-2000 Unimpaired



Natural downstream flows (cfs)Upstream flows

A

C

B

Statistical Relationships

Sum of Old and Middle River Flows

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Functional Flow Approach(Fleenor et al. 2010 paper)

Steps:1) Identify major ecosystem functions of flows

• Identify flow locations• Fish passage and behavioral cues• Habitat support• etc.

2) Estimate flows needed for each function, by season and annual frequency

3) Accumulate flows (without double-counting)4) Refine and finalize5) Improve over time

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Functional Flow ApproachCategory Item Function Flow Months Applied (10 = October) (cfs) 10 11 12 1 2 3 4 5 6 7 8 9

# Years of 10

1a juvenile salmon, adult splittail most years 2,500* 1 1 1 8 1. Yolo

Bypass 1b juvenile salmon, adult splittail pulses 4,000** 1 1 6

2a SR adult salmon 10,000 1 1 1 1 1 1 1 1 1 6 2b Juvenile salmon migration – SR 25,000 1 1 1 1 6 2c Adult sturgeon 70,000 1 1 1 1 1 1

2. Sac River 2d Min flow past PC intake 10,000 1 1 1 1 1 1 1 1 1 1 1 1 10

3a SJR juvenile salmon wet 20,000 1 1 1 2 above normal 15,000 1 1 ½ 4 below normal 10,000 1 1 6 dry 7,000 1 ½ 8 critical 5,000 1 10 3b Stockton Ship Channel DO 2,000 1 1 1 1 10

3. SJ Valley

3c SJR adult salmon 2,000 1 1 1 1 1 1 1 1 1 1 1 1 10 4a Mokelumne River flows 1,500 1 1 8 4. Eastside

Streams

4b Eastside Stream minimum flows 1,060 1 1 1 1 1 1 1 1 1 1 1 1 9 5a Delta smelt flows 48,000 1 1 1 5

5b Egeria suppression by reducing outflows (Experimental Flow) 8,000 1 1 3 ***

5. Net Delta Outflows

5c Overbite clam suppression by increasing flows (Experimental Flow) 120,000 1 1 1 3

6a Suisun Marsh Flows 6b Close or Limit exports Other 7a Safety Factor 20%

*, ** Yolo Basin flows require flows of 45,750 and 50,100 cfs with current understanding of the weir *** Flow is specified during driest of 10 years while all others are for wettest years

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Functional Flow ApproachScientific support for each flow:1a. & 1b. BDCP draft report 2008 , Moyle et al. 2004; Sommer et al. 2004;

Harrell and Sommer 2003; Harrell et al. 20091c. BDCP draft report 2008 2a. & 2b. Newman and Rice 2002, Williams 2006; Harrell et al. 2009,

USFWS Exhibit 31 1987, Kjelson and Brandes 19892c. Harrell and Sommer 2003 2d. Newman and Rice 2002 3a. CDFG 2005, USFWS Exhibit 31 1987, Newman and Rice 2002,

Williams 20063b. Lehman et al. 2004, Jassby and Van Nieuwenhuyse 2005, USFWS

Exhibit 31 1987, Newman and Rice 2002, Williams 2006 3c. USFWS Exhibit 31 1987, Newman and Rice 2002, Williams 2006 4a. Henson et al. 2007 4b. Moyle et al. 2007 5a. Bennett 2005, Hobbs et al. 2005 5b. Hauenstein and Ramirez 1986 5c. Thompson 2005, Moyle personal comm.6a. Bennett personal comm.

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Percentile Application of Functional Approach

80 %-ile

0

2

4

6

8

Oct

Nov Dec Jan

Feb

Mar Apr

May Jun Jul

Aug

Sep

Mon

thly

Vol

ume

(maf

)

Yolo BasinSAC RSJREastsideOutf lowUnimpairedNet Required

60 %-ile

0

2

4

6

8

Oct

Nov Dec Jan

Feb

Mar Apr

May Jun Jul

Aug Sep

Mon

thly

Vol

ume

(maf

)


40 %-ile

0

2

4

6

8

Oct

Nov Dec Jan

Feb

Mar Apr

May Jun Jul

Aug

Sep

Mon

thly

Vol

ume

(maf

)


20 %-ile

0

2

4

6

8

Oct

Nov Dec Jan

Feb

Mar Apr

May Jun Jul

Aug

Sep

Mon

thly

Vol

ume

(maf

)


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Implementing Functional Flows� Listed flows need further consideration

� Guidance needed to set functional flow levels

� Seasonal steps may miss smaller scale responses

� Some flow functions might conflict

� Are some important functions missing?

� How to work with experimental flows?

� Refine to integrate upstream uses

� Monitoring response is required

� Management flexibility is crucial

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Functional Flow Advantages� Organizes flow prescription around

ecosystem functions

� Ties flows to ecosystem functions

� Systematic approach to establishing and updating flow prescriptions

� Focuses scientific controversies

� Identifies weak areas of knowledge

� Allows for experimental/adaptive management flows

Fleenor et al. 2010

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Category Item Function Flow Months Applied (10 = October) (cfs) 10 11 12 1 2 3 4 5 6 7 8 9

# Years of 10

1a juvenile salmon, adult splittail most years 2,500* 1 1 1 8 1. Yolo

Bypass 1b juvenile salmon, adult splittail pulses 4,000** 1 1 6

2a SR adult salmon 10,000 1 1 1 1 1 1 1 1 1 6 2b Juvenile salmon migration – SR 25,000 1 1 1 1 6 2c Adult sturgeon 70,000 1 1 1 1 1 1

2. Sac River 2d Min flow past PC intake 10,000 1 1 1 1 1 1 1 1 1 1 1 1 10

3a SJR juvenile salmon wet 20,000 1 1 1 2 above normal 15,000 1 1 ½ 4 below normal 10,000 1 1 6 dry 7,000 1 ½ 8 critical 5,000 1 10 3b Stockton Ship Channel DO 2,000 1 1 1 1 10

3. SJ Valley

3c SJR adult salmon 2,000 1 1 1 1 1 1 1 1 1 1 1 1 10 4a Mokelumne River flows 1,500 1 1 8 4. Eastside

Streams

4b Eastside Stream minimum flows 1,060 1 1 1 1 1 1 1 1 1 1 1 1 9 5a Delta smelt flows 48,000 1 1 1 5

5b Egeria suppression by reducing outflows (Experimental Flow) 8,000 1 1 3 ***

5. Net Delta Outflows

5c Overbite clam suppression by increasing flows (Experimental Flow) 120,000 1 1 1 3

6a Suisun Marsh Flows 6b Close or Limit exports Other 7a Safety Factor 20%

*, ** Yolo Basin flows require flows of 45,750 and 50,100 cfs with current understanding of the weir *** Flow is specified during driest of 10 years while all others are for wettest years

developing flow prescriptions for the sacramento-san ... · (fleenor et al. 2010 paper) steps: 1)...

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