Colorado River Simulation System (CRSS)

Salinity Projection Model

October 20, 2004Colorado River Basin Salinity Control Advisory Council

Issues Addressed

• The model did not accurately simulate the historical period 1971-1990

• Problems Identified:– Changing natural flow and salt mass

relationship– Input data inconsistent– Limited and out-of-date documentation

Lake Powell inflow

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

1960

1961

1962

1963

1964

1965

1966

1967

1968

1969

1970

1971

1972

1973

1974

1975

1976

1977

1978

1979

1980

1981

1982

1983

1984

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

flo

w 1

000

AF

/sal

t 10

00 t

on

s

-300

-100

100

300

500

700

900

Sal

t m

g/L

Flow 1000-af Load 1000-tons Q Avg-60-82,83-86,87-00

Avg tons 60-82,83-86,87-00 Conc mg/L Avg mg/L 60-82,83-86,87-00

1960-1982 Salt Average=7258 tons/Yr, 1987-2000 Salt Average=5918 tons/Yr.

Our Solutions

• Develop a new natural salt model• Re-compute natural flow 1971-2000• Direct new research to better understand salt

loading resulting from irrigating agriculture• Complete peer reviews with journal articles and

supporting documentation• Prepare to move model input data to a secure

database• Involve States during entire process

Peer Reviews

• Article describing new salt model accepted in a peer reviewed scientific journal ( ASCE Journal of Environmental Engineering)

• 1971-1995 CU&L data reviewed and revised by UC Regional office

• Methods to distribute CU&L for computation of natural flow reviewed by UC Regional office

• Methods to compute natural flow and salt reviewed by UC/LC modeling team

• CRSS Salinity Projection model reviewed by the UC/LC modeling team

Publications

• “Statistical Nonparametric Model for Natural Salt Estimation,” ASCE Journal of Environmental Engineering, to be published January 2005.

• “Draft Upper Basin Consumptive Uses and Losses Report as Revised After Peer Review 1971-1995.”

• “Upper Colorado River Consumptive Use Determination at CRSS Natural Flow Node Locations CY 1971-1995.”

• “Natural Flow And Salt Computation Methods 1971-1995”

Concluding Remarks

• Reclamation has a working model that we have confidence in and can support

• New salt model can easily be updated• New methods and data in CRSS Salinity

Projection Model fully supported with documentation

• Reclamation has begun reviewing CRSS Salinity Projection Model runs with Salinity Forum TMS

• Future research targeted to address upcoming issues

Colorado River Simulation System (CRSS)

Salinity Projection Model

For further information:http://cadswes.colorado.edu/~prairie