Golden Alga (Prymnesium parvum) Salt River Lakes

Marc Dahlberg Water Quality Program Manager

March 8, 2011

Golden Alga Temperature range between 5 and 30

degrees Celsius Blooms occur when nutrients are readily

available. When nutrients become depleted toxins are

released. The potency of the Golden alga is nearly five

times greater at a pH 8.5 than it is at 6.5. Cells are very fragile and are easily ruptured Prefers a saline environment – does very well

in waters with conductivities over 2000 µmhos/cm

Diagnostic Features 8 – 11 microns

long 3 – 6 microns wide Nucleus is located

centrally between two chloroplasts

2 equal flagella and a well developed heptonema

Conductivity Saguaro - Canyon – Apache - Roosevelt

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

0

500

1000

1500

2000

2500

3000

Saguaro Canyon Apache Roosevelt

Year

Cond

uctiv

ity (µ

mho

s/cm

)

Conductivity Saguaro - Canyon - Apache

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

0

500

1000

1500

2000

2500

Saguaro Canyon ApacheCond

uctiv

ity (µ

mho

s/cm

)

Average Conductivity Saguaro - Canyon - Apache

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

0

500

1000

1500

2000

2500

Year

Cond

uctiv

ity (

µmho

s/cm

)

Average Conductivity Saguaro - Canyon - Apache

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

0

500

1000

1500

2000

2500

Year

Cond

uctiv

ity (

µmho

s/cm

)

Corb

ic-

ula R

odeo

- Ch

edis

ki Thre

adfin

sh

ad

All

sp

ecie

s

All

sp

ecie

s

Thre

ad fi

n

sh

ad

Thre

adfin

sh

ad

Average Conductivity Salt River Lakes (Saguaro-Canyon-Apache) and Salt River below Saguaro

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

0

500

1000

1500

2000

2500

Lakes Salt River

Year

Cond

uctiv

ity (µ

mho

s/cm

)

Conductivity Comparison19

5119

5419

5719

6019

6319

6619

6919

7219

7519

7819

8119

8419

8719

9019

9319

9619

9920

0220

0520

0820

11

0

500

1000

1500

2000

2500

Salt River Below Saguaro Average Saguaro, Canyon, ApacheYear

Cond

uctiv

ity (µ

mho

s/cm

)

Dead or DryRoosevelt Lake -

1928, 1929, 1930, 1931, 1934, 1938, 1940, 1947, 1950, 1951, 1956

San Carlos Lake –

1934, 1938, 1939, 1940, 1946, 1947, 1948, 1950, 1951, 1952, 1953, 1955, 1956, 1957, 1960, 1961, 1965, 1971, 1976, 1977

Bill Silvey

Average Conductivity Salt River Lakes (Saguaro-Canyon-Apache) and Roosevelt Lake

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

0

500

1000

1500

2000

2500

3000

Salt River Lakes Roosevelt Lake

Year

Cond

uctiv

ity (u

mho

s/cm

)

Roosevelt Lake20

00

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

0.000

0.500

1.000

1.500

2.000

2.500

3.000

Conductivity umhos/cm -3 Acre Feet -6

Salt River Flows and Conductivity 0-

500

501-

1000

1001

-150

015

01-2

000

2001

-250

025

01-3

000

3001

-350

035

01-4

000

4001

-450

045

01-5

000

5001

-550

055

01-6

000

6001

-650

065

01-7

000

<700

00500

100015002000250030003500

Cubic Feet per Second

Cond

uctiv

ity (µ

mho

s/cm

)

Tonto Creek Flows and Conductivity

0-10

0

101-

200

201-

300

301-

400

401-

500

>100

00

100

200

300

400

500

600

Cubic Feet per Second

Cond

uctiv

ity(µ

mho

s/cm

)

Roosevelt LakeSeptember 15, 2000 Conductivity

1392

1801

2125

Average Annual Flows at Salt River Diversion Dam

1914

1918

1922

1926

1930

1934

1938

1942

1946

1950

1954

1958

1962

1966

1970

1974

1978

1982

1986

1990

1994

1998

2002

2006

2010

0500

100015002000250030003500

Year

CFS

Golden Alga Caused Fish Kills in Waters without Forest Fires

Lake Conductivity

Kearney Lake

Water Ranch

Lake Las Vegas

2500 – 8500

2700 – 2900

2500 - 2900

Waters with Forest Fires that Have Not Resulted in a Golden Alga Fish Kill

Lake Conductivity

Horseshoe

Bartlett

Black Canyon Lake

400 – 750

400 – 700

50 -225

July 2002

July 19, 2002Conductivity 2570 Flow 263

July 31, 2002Conductivity 753 Flow 900

Questions?

September 14, 2011 Conductivity 1814 Flow 288 CFS

Roosevelt 1091 1.185 million AFApache 1067Canyon 1045Saguaro 1062

Salt River Lakes – Drainage Area

Roosevelt – 5830 square miles Apache – 5842 square miles (12 sq mi) Canyon – 6101 square miles (259 sq

mi) Saguaro – 6330 square miles (229 sq

mi)

92% of the watershed lies above Roosevelt dam

Salt River Lakes - Storage

Roosevelt – 1,653,043 acre feet (81%) Apache – 245,138 acre feet (12%) Canyon Lake – 57,832 acre feet (3%) Saguaro – 73,613 acre feet (4%) Total – 2,029,646 acre feet

Conductivity

The specific conductance test measures the ability of water to pass an electrical current. Conductivity in water is affected by the presence of inorganic dissolved solids such as chloride, sulfate, sodium, calcium and others. The greater the concentrations of ions, the larger the conductivity.

0

500

1000

1500

2000

2500

Year

Cond

uctiv

ity (µ

mho

s/cm

)Salt River Below Saguaro Lake