U.S. Department of the Interior

U.S. Geological Survey

Water Temperature Modeling 

Water Temperature Modelin

Scott Wright, Craig Anderson, Nick Vo

Scott Wright, Craig Anderson, Nick Vo
Data Report Data Report

 Mainstem and tributary water temperature 

Mainstem and tributary water temperature 

by GCMRC since 1988 by GCMRC since 1988“Water Temperature Data for the Colorado River and T

“Water Temperature Data for the Colorado River and T

Glen Canyon Dam and Spencer Canyon, Northeastern 

Glen Canyon Dam and Spencer Canyon, Northeastern 

By Nicholas Voichick and Scott Wright By Nicholas Voichick and Scott Wright

 Summary of methods for data collection, Q

Summary of methods for data collection, 

basic statistics basic statistics

 Currently in USGS review Currently in USGS review Data files and report to be served over the 

Data files and report to be served over the 

website website – data files updated annually data files updated annually
Data Report Data Report - Tables

Site name Latitude Longitude Start of record End of record 

Colorado River below Glen 

Canyon Dam (CRBD) -111.4826 36.9361 10-Aug-88 Continuing 

Colorado River at Lees 

Ferry (CRLF) -111.5846 36.8653 10-Oct-91 Continuing 

Colorado River near river 

mile 30 (CR030) -111.8457 36.5201 26-Oct-02 Continuing 

Colorado River near river 

mile 33 (CR033) -111.8434 36.4861 14-Apr-00 28-May-05 

Colorado River near river 

mile 61 (CR061) -111.8003 36.1964 11-Aug-90 Continuing 

Site name 

Percent 

good 

data 

Mean 

(°C) 

Media

(°C) 

CRBD 80 9.4 9.2 

CRLF 84 9.8 9.5 

CR030 94 11.1 10.8 CR033 87 10.4 10.2 CR061 91 10.6 10.5 
6

8

10121416182022

Water Temperature (oC)

CRBD

CRLF

CR030

CR033

CR061

CR065

CR076

CR087

CR132

CR149

CR166

Data Report Data Report - Figures Figures

05

10152025303540

Water Temperature (oC)

ParR

NanCr

LCR

BACr

ShnCr

TapCr
Modeling Modeling – Why?

 Predictions Predictions – Evaluation of Alternatives (e

Evaluation of Alternatives (e

 Isolate effects of interest (e.g. fluctuation v

Isolate effects of interest (e.g. fluctuation 

while holding other drivers while holding other drivers contant contant

 Reduction in monitoring efforts Reduction in monitoring efforts Model development was a primary recom

Model development was a primary recom

the QW PEP the QW PEP
Modeling Approach Modeling Approach

 Mainstem one Mainstem one

-dimensional model dimensional model

 USGS Branched Lagrangian Transpor

USGS Branched Lagrangian Transpor

 Linked to existing UNSTEADY flow mo

Linked to existing UNSTEADY flow mo

 Similar to Reclamation 1D GEMSS mo

Similar to Reclamation 1D GEMSS mo

 Nearshore model Nearshore model

 Simplified representation of backwater

Simplified representation of backwater

 Complimentary to Reclamation 3D GE

Complimentary to Reclamation 3D GE
BLTM (Branched Lagrangian Transpo

Branched Lagrangian Transpo

 Developed and widely used by USGS ove

Developed and widely used by USGS ove

– open source code that can be modified open source code that can be modified

 Simulates fate of water quality constituent

Simulates fate of water quality constituent

channels and unsteady flow channels and unsteady flow – can incorpo

can incorpo

hydrodynamic information from external m

hydrodynamic information from external m

 Can route up to 10 interactive constituent

Can route up to 10 interactive constituent

reaction kinetics and concentrations (EPA 

reaction kinetics and concentrations (EPA 

user defined equations user defined equations

 Solves advective advective-dispersion equation usin

dispersion equation usin

reference frame reference frame – numerically accurate a

numerically accurate a
Temperature Modeling 101 Temperature Modeling 101

HE

S

x

T

D

xx

T

U

t

T ⎟ +

⎠⎞ ⎜

⎝⎛

∂

∂

∂

∂

+

∂

∂

=

∂

∂

Change in 

temperature

transport

Advective

Dispersive 

transport

Surface heat 

exchange

time

C

Advection Advection + 

dispersion
Temperature Modeling 101 Temperature Modeling 101

Calculation of Calculation of 

qnet requires detailed meteorologi

requires detailed meteorolog

BLTM uses simplified approach BLTM uses simplified approach 

– Equilibrium tem

Equilibrium tem

Requires only max/min daily Requires only max/min daily air temperature an

air temperature an
Available Meteorological Da

Available Meteorological Da

Location Location Period of Period of Record Frequency Frequency Elevation Elevation (ft) 

Page 1957 

– present present Hourly 4,200

3,2002,5306,8001,131

Air T

Air T

Spee

Spee

Cove

Cov

Lees Ferry Lees Ferry 1948 - present present Daily Max 

Max 

Prec

Phantom Phantom 

Ranch 1948 - present present Daily Max 

Max 

Prec

GCNP

(South Rim) (South Rim) 1903 

– present present Daily Max 

Max 

Prec

Lake Mead Lake Mead 2000 

– present present Hourly

Air T

Air T

and 

and 

Sola
Available Meteorological Da

Available Meteorological Da
1D Model Calibration 1D Model Calibration

 Year 2000 Year 2000 

– Range in water temper

Range in water tempe

and fluctuating flows, LSSF and fluctuating flows, LSSF

 Procedure Procedure

 Adjust wind function parameters Adjust wind function parameters 

– eva

eva

 Adjust equilibrium temperatures Adjust equilibrium temperatures 

– relat

relat

the meteorological data the meteorological data

 Minimize differences between measure

Minimize differences between measure

predicted water temperature predicted water temperature

 Experiment with Page and Mead mete

Experiment with Page and Mead mete
Calibration Results (Year 20

Calibration Results (Year 20

Incorporating Lake Incorporating Lake Mead meteorology Mead meteorology reduces errors in reduces errors in western Canyon western Canyon
2000 LSSF Warming Predic

2000 LSSF Warming Predic
1D Model Validation 1D Model Validation

 Run model for different time period 

Run model for different time period 

parameter adjustment parameter adjustment

 Year 2005 Year 2005 

– Variety of experimenta

Variety of experimenta

release temperatures release temperatures
Validation Results (Year 200

Validation Results (Year 200

Errors less than Errors less than calibration period calibration period
Validation Validation - Hourly Time Se

Hourly Time Se
Validation Validation - Daily Range Daily Range

Model tends to Model tends to slightly slightly underpredict daily predict daily 

temperature range temperature range - probably due to probably due to local effects local effects
Validation Validation – Daily Range Daily Range
1D Model Conclusions 1D Model Conclusions

 Predictions agree with measurements to w

Predictions agree with measurements to w

average average

 Incorporating Lake Mead meteorology im

Incorporating Lake Mead meteorology im

predictions in western canyon predictions in western canyon

 Slight under Slight under

-prediction of daily variation prediction of daily variation 

- 

improved but is it worth it? improved but is it worth it?

 Next steps Next steps

 Develop user Develop user

-interface for 1D model interface for 1D model

 Write

-up documentation for 1D model up documentation for 1D model

 Begin work on nearshore model Begin work on nearshore model 
Nearshore Model Nearshore Model

 Reclamation has developed a 3D flow and 

Reclamation has developed a 3D flow an

model for nearshore areas model for nearshore areas 

– limited to ap

limited to ap

reaches over short time periods reaches over short time periods

 Want to develop a nearshore model (part

Want to develop a nearshore model (part

backwaters) capable of simulating system backwaters) capable of simulating system– link dynamically with 1D model link dynamically with 1D model

 Need a simplified representation of nears

Need a simplified representation of nears

environments environments 

– in the process of reviewin

in the process of reviewin

(Craig Anderson talk this afternoon) (Craig Anderson talk this afternoon)