1

Delta Smelt

0.0

0.3

0.6

0.9

1.2

1.5

1.8

66 69 72 75 78 81 84 87 90 93 96 99 02 05 08 11

(Tho

usan

ds)

Abu

ndan

ce In

dex

Longfin Smelt

0

2

4

6

8

10

12

14

16

18

20

66 69 72 75 78 81 84 87 90 93 96 99 02 05 08 11

(Tho

usan

ds)

Abu

ndan

ce In

dex

Striped Bass

0

5

10

15

20

66 69 72 75 78 81 84 87 90 93 96 99 02 05 08 11

(Tho

usan

ds)

Abu

ndan

ce In

dex

Threadfin Shad

0

2

4

6

8

10

12

14

16

66 69 72 75 78 81 84 87 90 93 96 99 02 05 08 11

(Tho

usan

ds)

Abu

ndan

ce In

dex

Digital Map fromDr. William Bowen California State University Northridge

Sacramento-San Joaquin

DeltaSan Joaquin

River

Sacramento River

Suisun Bay

San Francisco

2

0 10 20 300

20

40

60

80

100Delta smelt

Thr. shadAm. shad

Striped bass

Chinook salmon

Salinity

C

um

ula

tive

Pe

rce

nt

Splittail

Most fishes follow salinities

Kimmerer 2004

Marine species

3

4

Most fish food follows salinities

5

0 50 100 150 200 250 300 3500

0

5

10

15

O N D J F M A M J J A S

Day of Water Year

W D

1983 1977 1998 1991 1995 1992 1982 1990 1958 1994 (1997)

Dry Years

Wet Years

Fre

shw

ater

Flo

w (

m3 s

-1)

Variability of Freshwater Delta Inflow

6

X2=

85

X2=

74

7

1967-871988-2000

1982-2000 (DS)All Years

1

2

3

4

1

2

3

4

0

1

2

3

2

3

4

5

0

1

2

3

2

3

4

5

50 60 70 80 90

0

1

2

3

50 60 70 80 90

-2

-1

0

1

Bay Shrimp

Striped BassSplittail

Longfin smeltDelta smelt

Herring Am. Shad

Flounder

Lo

g A

bu

nd

an

ce

or

Su

rviv

al

X2 (km)High Flow Low Flow

Source:Kimmerer 2002MEPS

Higher trophic levels show many

relationships of abundance to

freshwater flow

8

X2 (km)

0

1

2

0

1

2

1

2

3

4

1

2

3

4

50 60 70 80 90

2

3

4

5

50 60 70 80 90-2

-1

0

1

2

Mysid

Copepod: Spring

Copepod: Summer

Rotifer: Summer

Chlorophyll: SummerChlorophyll: Spring

Lo

g A

bu

nd

an

ce

X2(km)

High Flow Low Flow

Lower trophic levels show few relationships

of abundance to freshwater flow

Source:Kimmerer 2002 MEPS

1972-19871988-2000

9

X2 (km)

10

X2=74

11

X2=85

0

10000

20000

30000

40000

50000

1930 1940 1950 1960 1970 1980 1990 2000 2010

Aver

age

Fall

Outf

low

(cfs

)

W

AN

BN

D

C

13

14

Flows are important but so is geometry

Stationary Habitat ---Geometry

Dynamic Habitat ---Hydrodynamics, ocean conditions, weather

Environment

Biological Conditions

15

Estuarine habitat conceptual model(Peterson 2003)

Stationary Habitat

Dynamic Habitat

Production AreaTidal and River Flow

PelagicRecruitment

16

1873 Delta:

Long residence time

Marsh connections

Two rivers connect to bay

Waterways dendritic

17

Modern delta

Short residence times

Rip-rapped

Cross Delta flows

Rare San Joaquin connection to bay

Waterways web-like18

19Not stable

Old Regime

Variable, High

To the west, Variable

Complex, Variable

Low, Variable

High, Variable

High P, low N

Few, Low

Predation, Fishing

Environmental Drivers

Outflow

Salinity gradient

Landscape

Temperature

Turbidity

Nutrients

Contaminants

“Harvest”

New Regime

Variable, Lower

To the east, Constricted

Simplified, Rigid

High, Uniform

Low, Less variable

Low P, High N (NH4+)

Many, High

Predation and Entrainment

Natives dominatePelagic Fishes, Mysids, Large

Copepods, Diatoms

Invasives dominateEdge & Benthic Fishes, Clams,

Jellyfish, Small Copepods, Microcystis, Aquatic weeds

Higher After Wet Springs

Higher After Wet Springs

After Wet Springs, Broad Fall LSZOverlaps Suisun Region

Higher After Wet Springs

Higher After Wet Springs

More Variable, Higher After Wet Springs

More Variable, Maybe Lower After Wet Springs

Always Low

Always Low

Narrow Fall LSZ In River Channels,Never Overlaps Suisun Region

Always Lower

Always Lower

Always Less Variable, Lower

Less Variable, Maybe Higher

Bathymetric Complexity

Erodible Sediment Supply

Contaminant Sources

Entrainment Sites

Lower

Lower

Many

More

Net Total Delta Fall Outflow

San Joaquin River Contribution to Fall Outflow

Location and Extent of the Fall LSZ (1-6 psu)

Hydrodynamic Complexity in the Fall LSZ

Wind speed in the Fall LSZ

Turbidity in the Fall LSZ

Contaminant Concentrations in the Fall LSZ

Stationary Abiotic Habitat ComponentsSuisun Region River Confluence

Distribution

Growth, Survival, Fecundity

Health and Condition

Recruitment in the next Spring

Constricted, Eastward

Lower

Worse

Lower

Dynamic Abiotic Habitat ComponentsVariable Fall Outflow Regime Static Fall Outflow Regime

Dynamic Biotic Habitat ComponentsLSZ Overlaps Suisun Region LSZ Overlaps River ConfluenceFood Availability and Quality

Predator Abundance

Lower

Higher

Delta Smelt ResponsesLSZ Overlaps Suisun Region LSZ Overlaps River Confluence

X2=74km

X2=85km

21

Regulatory Approaches

FWS and NMFS(with DFG)

Biological Opinions to protect smelt and salmon:

In place and subject to 11lawsuits from

waterusers

Bay-Delta Conservation Plan:

in development

Regional Boards:New discharge permit for Sac Regional

TMDLs for salt, boron and

Selenium from San Joaquin

22

Regulatory Approaches 2

SWRCB

Issued flows report in 2010

Developing new standards for San Joaquin flows and south delta salinity

In 2012 will address Delta outflow requirements

EPA

ANPR in February 2011

What should be done about:

SeleniumContaminantsEmerging ContaminantsAmmoniumWetlandsEstuarine HabitatMigratory Corridors

How much water do fish need?

23

24

What Changes As Flow Increases?

X2Location of Any Salinity

RangeLSZ

Salinity and X2

FLOW

25

stratification

Flo

odpl

ains

ProportionDiverted

What Changes As Flow Increases?

DeltaResidence Time

RiverStage,

Velocity

River stage and velocity

Floodplain inundation

26

FLOW

FLOW

Upstream bottom current

NutrientsContaminantsOrganic matter

Sediment

What Changes As Flow Increases?

Concentrations

Loadings

27

FLOW

FLOW

What Changes As Flow Increases?

Adult spawners move up:SalmonGreen and White

SturgeonLongfin smeltDelta smeltSplittailAmerican shadPacific herring

Young Marine fish move up:Starry flounderWhite croakerPacific halibut

Young fish move down:SalmonLongfin smeltDelta smeltSplittailAmerican shadStriped bass

28

1.1. Environmental flows are more than just volumes of inflows Environmental flows are more than just volumes of inflows and outflowsand outflows

2.2. Recent flow regimes both harm native species and Recent flow regimes both harm native species and encourage non-native speciesencourage non-native species

3.3. Flow is a major determinant of habitat and transportFlow is a major determinant of habitat and transport

4.4. Recent Delta environmental flows are insufficient to support Recent Delta environmental flows are insufficient to support native Delta fishes for today’s habitatsnative Delta fishes for today’s habitats

5.5. A strong science program and a flexible management A strong science program and a flexible management regime are essential to improving flow criteriaregime are essential to improving flow criteria

Five Key Points

29

+

-

NutrientsOrganic matter

SedimentFish

Flo

odpl

ains

ProportionDiverted

What Changes As Flow Increases?

X2

-Delta

Residence Time

-

RiverStage,

Velocity

+

Location of Any Salinity

Range

-SalinityAt a Point

LSZ

30

Delta smelt habitat abundance in relation to X2

31

FishProduction

BenthicProduction

Zooplankton Production

MicrobialProduction

PhytoplanktonProduction

Nutrient Input

Organic InputInputs

Hydrodynamic Forcing:

Freshwater inflowOceanic variability

Wind

Stratification

Transport/Retention

PhysicalHabitat

Physical forcing

mechanisms

Material flows

Direct physical

influences

Key feedback

loop

Conceptual Model:Physical effects on estuarine ecosystem

32