developing flow prescriptions for the sacramento-san ... · (fleenor et al. 2010 paper) steps: 1)...
TRANSCRIPT
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
2
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
4
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
1986-2005 Historical
6
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
1986-2005 Historical
7
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
1986-2005 Historical
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
9
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)
�
��
��
��
��
��
��
��
�
�
���
���
���
���
���
���
���
���
���
���
��
��
��
��
����
����
�� ���� ��� ��
������ ���� ����������
!"�� ���#$%���$�!�
&������'
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
1921-2003 Unimpaired
1949-1968 Historical
1986-2005 Historical
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
1949-1968 Historical
1986-2005 Historical
Natural downstream flows (cfs)Upstream flows
A
C
B
Statistical Relationships
Sum of Old and Middle River Flows
13
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
14
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
15
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.
16
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
)
Yolo BasinSAC RSJREastsideOutf lowUnimpairedNet Required
40 %-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
20 %-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
17
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
18
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
19
20
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