U.S. Department of the Interior

U.S. Geological Survey

Nearshore Water Temper

Nearshore Water Temper

Measurements and Moni

Measurements and Moni

Craig Anderson and Scott Wright Craig Anderson and Scott WrightGCMRCAugust 2, 2006 August 2, 2006
Overview Overview

 Review recent nearshore and bac

Review recent nearshore and bac

collection efforts (2004 & 2005) collection efforts (2004 & 2005)

 Identify water temperature trends 

Identify water temperature trends 

with steady and fluctuating flows with steady and fluctuating flows

 Future nearshore temperature da

Future nearshore temperature da

efforts efforts
Nearshore Aquatic Environ

Nearshore Aquatic Environ

 Low velocity, warm water Low velocity, warm water 

habitats habitats

 Refugia and nursery Refugia and nursery 

habitats for young, native habitats for young, native fish

 Potential aquatic foodbase Potential aquatic foodbase 

hot spots hot spots

 Link between aqu Link between aquatic and atic and 

terrestrial ecosystems terrestrial ecosystems
Data Reports Data Reports

 “Effects of Air and Mainstem Water Tempe

Effects of Air and Mainstem Water Tempe

Isolation, and Fluctuating Fl Isolation, and Fluctuating Flows From Gle

ows From Gle

Water Temperatures in Nearshore and Bac

Water Temperatures in Nearshore and Bac

Environments in the Colorado River in Gra

Environments in the Colorado River in Gra

Korman, Kaplinski, and Buszowski, 2005 Korman, Kaplinski, and Buszowski, 2005

 August – October 2004 October 2004 Examined effects of hydraulic isolation an

Examined effects of hydraulic isolation an

gradient on vertical and lateral temperatur

gradient on vertical and lateral temperatur

nearshore environments nearshore environments
Study Sites Study Sites

C

Eminence
Sensor Configuration and Depl

Sensor Configuration and Dep

2,500

17,500

15,000

12,500

10,000

7,5005,000

20,000

8,000 cfs

18,000 cfs

 Replicate lines at steep talus shorelin

Replicate lines at steep talus shorelin

sandy shoreline, and backwater habitat

sandy shoreline, and backwater habita
 Nearshore temps maximum 2-3 °C warmer 

 Greater warming under 5-10 kcfs regime Greater discharge fluctuations = reduced w Strong effect of site isolation with backwat

greatest warming. Inconsequential warminhabitats.

 Vertical stratification in backwaters (max d

However, differences typically only for shoisolated locations, and within fluctuating z

Major Findings Major Findings
Recommendations Recommendations

 Supplement mainstem monitoring 

Supplement mainstem monitorin

 Continuous stage and temperature s

Continuous stage and temperature s

 $400 per unit $400 per unit

 Modify temperature sensor line d

Modify temperature sensor line d

provide more consistent perform

provide more consistent perform

fluctuating flows fluctuating flows
Design Limitations Design Limitations

 Sensor exposure in fluctuating zo

Sensor exposure in fluctuating zo

 Sensor stability during high flows 

Sensor stability during high flows 

 Datalogger and power failures Datalogger and power failures Floatation visibility issues Floatation visibility issues
Data Delivery Report Data Delivery Report



“Nearshore Water Temperature Data: A

Nearshore Water Temperature Data: A

November 14, 2005” November 14, 2005” 

– Matt Kaplinski, 2

Matt Kaplinski, 2

 Measured nearshore water temperature

Measured nearshore water temperature

aquatic habitats during the 2005 low aquatic habitats during the 2005 low-vo

vo

experiment. experiment.

 Examined vertical and lateral water tem

Examined vertical and lateral water tem

gradients at 10 sites gradients at 10 sites
Study Sites Study Sites

RM 41

RM 65 RM 68

RM 127

RM 213
Water level

1

Sensor Configuration and Deplo

Sensor Configuration and Deplo

Rocks

Sen

 One string within One string within backwater backwater and o

and o

within same within same eddy system eddy system
Aug 12 – Nov 14 GCD Disch

Nov 14 GCD Disch

Steady 8 kcfs

6-9 kcfs

10-18 kcfs
RM45 Backwater Temperatu

RM45 Backwater Temperatu

Later

Later

- Sep

Sep

- Sep- Oct 

Oct 

- Oct 

Vertic

Vertic

- Sep

Sep

- Sep- Oct 

Oct 

- Oct 
RM 68 Backwater Temperat

RM 68 Backwater Temperat

Later

Later

- Sep

Sep

- Sep- Oct 

Oct 

- Oct 

Vertic

Vertic

- Sep

Sep

- Sep

- Oct 

Oct 

- Oct 
RM 214 Backwater Tempera

RM 214 Backwater Tempera

Later

Later

- Sep

Sep

- Sep- Oct 

Oct 

- Oct Vertic

Vertic

- Sep

Sep

- Sep

- Oct 

Oct 

- Oct 
Preliminary Findings Preliminary Findings

 Backwater temps on average 2 Backwater temps on average 2

-4 

°C warm

C war

associated eddies during summer month

associated eddies during summer month

 Similar temperature gradients at 6 Similar temperature gradients at 6

-9 kcfs 

9 kcfs 

and steady 8 kcfs flows (slightly greater 

and steady 8 kcfs flows (slightly greater 

 However However, individual backwaters exhibit d

, individual backwaters exhibit d

temperature trends as a function of geom

temperature trends as a function of geom

from the mainstem, and local insolation 

from the mainstem, and local insolation 
Design Limitations Design Limitations

 Flotation camouflage and stability Flotation camouflage and stabilit Nearshore sensor exposure durin

Nearshore sensor exposure durin

fluctuations fluctuations

 Surface sensor drift during low d

Surface sensor drift during low d
Future Nearshore Monitorin

Future Nearshore Monitorin

 Campaign Campaign

-based measurements based measurements

 Intensive spot sampling at individua

Intensive spot sampling at individua

 Longitudinal, lateral and vertical tra

Longitudinal, lateral and vertical tra

 Better characterize spatial variability 

Better characterize spatial variability 

degree of mixing degree of mixing

 Identify optimal locations for long Identify optimal locations for long

-te

te

deployments deployments
Future Nearshore Monitoring Future Nearshore Monitoring

 Long-term, continuous measurements 

 Better understanding spatial and temporal  Examining the impact of nearshore tempera

native fisheries, aquatic foodbase productiecosystem health

 Downstream thermal model calibration and 

 Modification of previously deployed se Feasibility experimentation System wide approach