1

Overview of South Yuba River HydrologyBob Center

Presented to FERC Academy on December 10, 2005

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South Yuba River, Edwards Crossing, May 20, 2005, 14,000 cfs

3

Introduction• The FERC re-licensing process has as a primary concern some re-allocation of South

Yuba River watershed runoff. At the heart of any new license will be a specification of how much water is to be returned to the rivers and creeks, water temperature, and how the water is to be distributed through time.

• An understanding of the runoff that is to be the object of this re-allocation will improve understanding of possibilities and constraints, and can assist in articulating interests in discussions with other stakeholders

• This presentation will provide an overview of runoff in the South Yuba watershed in basic terms:

– How much runoff there is, where it comes from, and when, and where it goes– The great variability of precipitation and runoff on all time scales – How dams and diversions impact the rivers and creeks in terms of reduction in volume,

continuity and variability• First is an overview of runoff in the watershed as a whole, including the over-all

effects of dams and diversions• Next is a look at the impact that dams and diversions have on:

– Middle Yuba River– Canyon Creek– Fordyce Creek– South Yuba above Spaulding Reservoir– South Yuba below Spaulding Reservoir

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Major Streams, Reservoirs and Conduits in the South Yuba Watershed

Weber Peak8092

Castle Peak9103

Black Buttes

8030

S. Yuba

S. Yuba

Fordyce

Poo

r Man

M. Yuba

S. Yuba Canal

Can

yon

+

+

+

Drum Canal

+Mt Lincoln8382

L Spaulding

Jackson Meadows Res

Fordyce L

Milton Res

Bowman L

Milton -Bowman

Canal

Bowman -SpauldingCanal

Scotchm

an

Jefferson

Humbug

Sprin

g

Rock

Englebright Res

Washington

Sha

dy

Kentucky Owl

Rush

South Yuba Watershed

5

S Yuba River

Fordy

ce

S Yuba River

97

93

343

200

172

Poo

rman

Cre

ek

50

Pre-Development South Yuba River Basin Hydrology vs Current Hydrology

(Data from USGS 1999 Hydrological Data Report)

Jones Bar(Hwy 49)

Note that many creeks enter the river below Poorman Creek, adding about 140,000 af, mostly from rain.

Creek

57

96

Can

yon

Cre

ek

96

279

279

282

200

Today’s Flow

Additional flow were there no diversions

Average Recorded Yearly Flow (‘000s of acre feet)

Yearly flow estimate (‘000s of acre feet)

Flow Scale: ¼” = 100,000 acre feet / year

720

97

6

Runoff above Lake Spaulding530,000 af / yr

(Includes 158,000 af from Bowman-

Spaulding canal, which include 62,000

af from the Middle Yuba)

South Yuba River93,000 af / yr

South Yuba Canal62,000 af / yr

Drum Canal375,000

af / yr

Release to River

Late Spring Spill 85,000 af /yr*

LakeSpaulding

Lake Spaulding Stores and Distributes Upper South Yuba River Water(Data from USGS 1999 Hydrological Data Report)

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Spaulding

el 5011’

Bowman

el 5558’

Fordyce

el 6402’

S Yuba River

Fordy

ceBow

man

-Spa

uldi

ng C

ana

l

Can

yon

Cre

ekPoor

man

Cre

ek

Drum Canal

South Yuba

S Yuba River

375

97

85

62

62

Canal

Milt

on-B

owm

anC

anal

(F

rom

M Y

uba)

200

172

25

4350

158

200

Major Reservoir

Natural Runoff

Diverted Runoff

Average Recorded Yearly Runoff (000s of acre feet)

Estimated Yearly Flow (000s of acre feet)

Flow Scale: ¼” = 100,000 acre feet / year

Overview of Present-Day South Yuba River Hydrology

(Data from USGS 1999 Hydrological Data Report)

Town of Washington

Note that many creeks enter the river below Lake Spaulding, adding about 146,000 af, mostly from rain

Creek

158

2.5

2.5

5

Release to River from Bowman and Spaulding

Jones Bar(Hwy 49)

239

Spill

99

14

343

99

5

8

South Yuba River Runoff and Water Distribution

0

200,000

400,000

600,000

800,000

1,000,000

1,200,000

1,400,000

1,600,000

71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 0 1 2 3 4

Water Year

Ac

re F

ee

t P

er

Ye

ar

L Cyn Runoff

Spill

Rel to S Yuba

S Yuba Canal

Drum Canal

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South Yuba River Runoff and Water Distribution

0

200000

400000

600000

800000

1000000

1200000

1400000

160000077 88 87 92

1

76 94 91 90 81

2

79

4

72 89

0

75

3

78 73 74 71 93 99 80 98 96 86 97 84 95 85 82 83

Water Year

Acr

e Fe

et P

er Y

ear L Cyn Runoff

SpillRel to S YubaS Yuba CanalDrum Canal

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Middle Yuba River and Milton Bowman Canal

Weber Peak8092

Castle Peak9103

Black Buttes

8030

S. Yuba

S. Yuba

Fordyce CrP

oor M

an C

r

M. Yuba

S. Yuba Canal

Can

yon

Cr

+

+

+

Drum

Canal

+Mt Lincoln8382

L Spaulding

Jackson Meadows Res

Fordyce L

Milton Res

Bowman Res

Milton -Bowman

Canal

Bowman -SpauldingCanal

Hwy 49(Jones Bar)

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Impact of Jackson Meadows Reservoir, Milton Dam and Milton-Bowman Canal on Flow Volume on the Middle Yuba River

Note: “Pre Dev” means that the data represents the flow before the construction of the dams and diversions immediately upstream (calculated using the equation “Input – Output = Change in Storage”). The date range “71-04” gives the time period covered by the data used in the continuity calculation. Where a date range appears by itself, such as “’88-’04”, the data represents post-development gauge readings, in this case below Milton Dam.

M Yuba blw Milton Lk Then and Now

0

50

100

150

200

250

300

350

400

450

CF

S

Pre Dev '71-'04 31 43 60 99 88 133 250 379 198 32 10 16

Pre-Dev '88-'04 4 20 54 96 79 152 267 419 206 33 3 1

88-'04 4 4 4 38 19 11 22 74 111 24 4 4

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

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Impact of Jackson Meadows Reservoir, Milton Dam and Milton-Bowman Diversion on Flow Volume and Variability in the Middle Yuba River

O J

A

J

1988

1990

1992

1994

1996

1998

2000

2002

2004

0

100

200

300

400

500

600

700

800

900

CFS

M Yuiba bl Milton L, Pre Development

O

F

J

1988 1990 1992

1994

1996

1998

2000

2002

2004

0

100

200

300

400

500

600

700

800

900

CFS

MY bl Milton Post Development

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Bowman Reservoir, Bowman-Spaulding Canal, and Canyon Creek

Weber Peak8092

Castle Peak9103

Black Buttes

8030

S. Yuba

S. Yuba

Fordyce CrP

oor M

an C

r

M. Yuba

S. Yuba Canal

Can

yon

Cr

+

+

+

Drum

Canal

+Mt Lincoln8382

L Spaulding

Jackson Meadows Res

Fordyce L

Milton Res

Bowman Res

Milton -Bowman

Canal

Bowman -SpauldingCanal

Hwy 49(Jones Bar)

14

Impact of Bowman Reservoir and the Bowman-Spaulding Canal on Flow Volume In Canyon Creek

Canyon Creek Then and Now

0

50

100

150

200

250

300

350

400

Monthly Averages '71-74

CF

S

Pre Dev '71-'04 38 73 120 143 134 193 250 358 193 47 12 13

71-'04 5 6 13 23 19 37 33 69 72 13 4 4

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

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Impact of Bowman Reservoir and Bowman-Spaulding Canal on Flow Volume and Variability In Canyon Creek

O

M

1971

1974

1977

1980

1983

1986

1989

1992

1995

1998

2001

2004

0

100

200

300

400

500

600

700

800

900

cfs

Canyon Ck Pre Development

O

M

1971

1974

1977

1980

1983

1986

1989

1992

1995

1998

2001

2004

0

100

200

300

400

500

600

700

800

900

CFS

Canyon Creek Post Development '71-'04

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Fordyce Lake and Fordyce Creek

Weber Peak8092

Castle Peak9103

Black Buttes

8030

S. Yuba

S. Yuba

Fordyce CrP

oor M

an C

r

M. Yuba

S. Yuba Canal

Can

yon

Cr

+

+

+

Drum

Canal

+Mt Lincoln8382

L Spaulding

Jackson Meadows Res

Fordyce L

Milton Res

Bowman Res

Milton -Bowman

Canal

Bowman -SpauldingCanal

Hwy 49(Jones Bar)

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Impact of Fordyce Lake on Flow TimingIn Fordyce Creek

Fordyce Ck blw Fordyce Lk

0

50

100

150

200

250

300

350

400

450

500

Monthly averages '77-'95

CF

S

Pre Dev 46 53 68 99 229 433 332 104 28

77-'95 118 68 32 40 36 51 78 195 324 279 174 106

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

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Impact of Fordyce Lake on VariabilityIn Fordyce Creek

O

J

A

J

1977

1978

1979

1980

1981

1982

1983

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

-100

0

100

200

300

400

500

600

700

800

900

1,000

CFS

Fordyce Ck bl Fordyce Lk Pre Project

O

M

A

1977 19

79 1981 1983 1985 1987 1989 1991 1993 1995

0

100

200

300

400

500

600

700

800

900

1000

CFS

Fordyce Ck bl Fordyce Lk Post Project

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South Yuba River above Lake Spaulding

Weber Peak8092

Castle Peak9103

Black Buttes

8030

S. Yuba

S. Yuba

Fordyce CrP

oor M

an C

r

M. Yuba

S. Yuba Canal

Can

yon

Cr

+

+

+

Drum

Canal

+Mt Lincoln8382

L Spaulding

Jackson Meadows Res

Fordyce L

Milton Res

Bowman Res

Milton -Bowman

Canal

Bowman -SpauldingCanal

Hwy 49(Jones Bar)

20

The South Yuba above Lake Spaulding

The South Yuba above Cisco is relatively unimpaired

0

100

200

300

400

500

600

700

800

'71-'94 39 120 95 115 138 234 424 685 388 71 15 23

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

O

M

A

1971

1973

1975

1977

1979

1981

1983

1985

1987

1989

1991

1993

0

200

400

600

800

1,000

1,200

1,400

1,600

CFS

South Yuba at Cisco Grove

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Lake Spaulding, the Drum Canal,theSouth Yuba Canal and the South Yuba River

Weber Peak8092

Castle Peak9103

Black Buttes

8030

S. Yuba

S. Yuba

Fordyce CrP

oor M

an C

r

M. Yuba

S. Yuba Canal

Can

yon

Cr

+

+

+

Drum

Canal

+Mt Lincoln8382

L Spaulding

Jackson Meadows Res

Fordyce L

Milton Res

Bowman Res

Milton -Bowman

Canal

Bowman -SpauldingCanal

Hwy 49(Jones Bar)

22

Dams and diversions have great imnpact on flow volume and flow variability in the South Yuba River

0

200

400

600

800

1,000

1,200

1,400

1,600

Langs X '77-94 7 67 71 46 113 99 99 282 324 58 6 6

Pre Dev 233 295 311 423 668 961 1,415 887 230 12

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

Lake Spaulding, the Drum Canal,theSouth Yuba Canal and the South Yuba River

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The South Yuba canyon between Fordyce Lake and Englebright Lake produces a large volume of

unimpaired runoff. Accretion from 44 miles of the South Yuba, 9 miles of Canyon Creek below Bowman L, 12

miles of Poorman Creek and numerous smaller creeks creates a “new” river with substantial natural flow and

significant natural variability at all scales.

O

A

1971

1973

1975

1977

1979

1981

1983

1985

1987

1989

1991

1993

1995

1997

1999

2001

2003

0

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

4,500

5,000

CFS

Lang's Crossing

O

A

1971

1973

1975

1977

1979

1981

1983

1985

1987

1989

1991

1993

1995

1997

1999

2001

2003

0

500

1,000

1,500

2,000

2,500

3,000

3,500

4,000

4,500

5,000

CFS

Jones Bar

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In this late season rain and rain-on-snow event, dams on the Yuba attenuate the river’s response when compared to the North American, a similar river

(View at 200% to see labels)

25

Spring snowmelt causes daily variation in flow. Enough snowmelt escapes dams to provide some daily

variation on the South Yuba (View at 200% to see labels)