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PROGRAM ELEMENT

 
 
     Name:  Clifton Court Forebay Temperature Study
     Program Manager:
     Ted Sommer
     California Department of Water Resources
     3251 S Street
     Sacramento CA  95816
     (916) 227-7537

Purpose/Objective: 

     This study will determine whether water is warmed after
being diverted into Clifton Court Forebay.  Temperature effects
are an important consideration in evaluating project alternatives
in relation to impacts on the aquatic environment and fisheries
community, particularly salmon.  Warming of water across the
present forebay is a potential concern.  

Geographic Range of Field Work:

     All field work is conducted in Clifton Court Forebay,
located in the south Delta (Latitude 37 Degrees 51 Minutes,
Longitude 121 Degrees 35 Minutes).

Number of sites:  Three

Site 1:  Radial gates water quality station (Intake to forebay)
Site 2:  Forebay outlet, next to approach channel for Skinner
          Fish Facility
Site 3:  Skinner Fish Facility Trash Racks

Period of Record:  

     Station 1 and 3:  May, 1993-
     Station 2:  July 1993-

Size for complete data base for program element in KB:  740 

Number of individual files:  3

Sample frequency per time unit:  

     One temperature recording each hour

General category of data collected:

     Temperature (degrees centigrade)

Comments about element:

     Stations 1 and 3 are water temperature stations only (1
meter depth).  Station 2 includes both water temperature (3 meter
depth) and air temperature ("0 meters depth").  Note that
additional probes were installed at Station 2 (1 meter), Station
3 (3 meters) and a raft located in front of the radial gates (1
meter), but all malfunctioned during the course of the study and
the data are considered unreliable.

Field Sampling

     Field collection of temperature data is performed by DWR's
Delta Field Division.  Easylogger Model ES-060 temperature probes
(Omnidata International, Tel. 801-753-7760) are placed in situ at
forebay Sites 2 and 3.  At Site 1 water is pumped continously
into a shore-based water quality station from a pipe located in
front of the forebay radial gates.  Sample is discharged into a
plastic drum, where temperatures are measured by another Model
ES-060 probe.  The specifications of the temperature probes
indicate probe accuracy is +/- 0.25 degrees Centigrade.

     Data at all stations are logged hourly by a battery-operated
Omnidata Easy Logger.  System components include a Easy Logger
Field Unit (Model EL-824) and a 64K EPROM Data Storage Pack
(Model EM-064).  A portable Easy Logger Terminal (Model EL-820)
is used to download data from the loggers.

Data Analysis

     Data analysis is performed by the Project Manager.  A
spreadsheet program (Lotus 123V5) is used for quality control and
data analysis.  All files are inspected for outliers and missing
data in three ways:  1)  Data are plotted individually; 2) data
are plotted against the other stations and; 3) data are sorted
from largest to smallest value. Data gaps or problems comprising
a single hourly measurement are filled by interpolation from the
previous and following hours.  In the rare cases of repeated
problems or gaps, data are replaced by a "blank".