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Clear Creek Water Temperature Threshold Analysis

Ecological Thresholds Queries

This page provides analysis, based on Reclamation 2019 Proposed Action, of current and historical water temperature conditions for fish using only observed data. Actual pre-season and in-season management decision processes are complex employing multiple sources of observed data, models, and forecasts. For further information, see the Thresholds section.



Note: Years prior to 2019 pre-date the Reclamation Proposed Action and are provided for historical perspective on conditions.

Line chart for 2024 Clear Creek daily average control regulating discharge at Whiskeytown (WHI), flow near Igo (IGO), and water temperature near Igo (IGO). Threshold lines for Juvenile Steelhead and Spring-run Chinook Adults at 60°F and Spring-run Chinook Eggs and Pre-emergent Fry at 56°F. Water temperature (in degrees Fahrenheit) and flow in cubic feet per second (CFS). Data retrieved from CDEC; figure generated by SacPAS.
2024 Water Temperature Threshold Analysis and Exceedance
Life Stage Life Stage
Dates
Criterion Possible
Days
Data
Days
Missing
Data
Days
Total Period Analyzed Criteria Exceedance
Average
Water
Temperature
Days in
Threshold
Days First Day Last Day
Juv Steelhead/Spring-Run Adults 6/1-9/15 Below/Equal 60°F 107 107 0 57.8°F 107 0    
Spring-Run Eggs/Pre-emergent Fry 9/16-10/31 Below/Equal 56°F 46 23 0 56.8°F 1 22 09/16 10/08
Clear Creek Water Temperature Threshold Analysis History
2024 Clear Creek Water Temperature Threshold Analysis Data Table for Clear Creek nr Igo (IGO)
Date Value Juvenile/Adults
60°F
6/1-9/15
Eggs/Fry
56°F
9/16-10/31
Date Value Juvenile/Adults
60°F
6/1-9/15
Eggs/Fry
56°F
9/16-10/31
2024-10-08 56.10   Above
2024-10-07 56.25   Above
2024-10-06 56.20   Above
2024-10-05 55.86   Below
2024-10-04 56.14   Above
2024-10-03 56.43   Above
2024-10-02 56.56   Above
2024-10-01 56.56   Above
2024-09-30 56.54   Above
2024-09-29 56.53   Above
2024-09-28 56.58   Above
2024-09-27 56.91   Above
2024-09-26 57.03   Above
2024-09-25 57.18   Above
2024-09-24 57.40   Above
2024-09-23 57.60   Above
2024-09-22 57.29   Above
2024-09-21 57.33   Above
2024-09-20 57.32   Above
2024-09-19 57.54   Above
2024-09-18 57.43   Above
2024-09-17 56.64   Above
2024-09-16 56.36   Above
2024-09-15 57.24 Below  
2024-09-14 56.88 Below  
2024-09-13 57.65 Below  
2024-09-12 57.69 Below  
2024-09-11 57.14 Below  
2024-09-10 58.07 Below  
2024-09-09 57.64 Below  
2024-09-08 57.72 Below  
2024-09-07 58.31 Below  
2024-09-06 58.58 Below  
2024-09-05 58.47 Below  
2024-09-04 58.14 Below  
2024-09-03 58.05 Below  
2024-09-02 57.97 Below  
2024-09-01 58.49 Below  
2024-08-31 58.65 Below  
2024-08-30 58.53 Below  
2024-08-29 58.48 Below  
2024-08-28 58.73 Below  
2024-08-27 58.54 Below  
2024-08-26 58.40 Below  
2024-08-25 57.98 Below  
2024-08-24 57.70 Below  
2024-08-23 56.73 Below  
2024-08-22 58.46 Below  
2024-08-21 58.63 Below  
2024-08-20 58.24 Below  
2024-08-19 58.20 Below  
2024-08-18 58.30 Below  
2024-08-17 58.05 Below  
2024-08-16 59.06 Below  
2024-08-15 58.76 Below  
2024-08-14 58.47 Below  
2024-08-13 58.28 Below  
2024-08-12 59.00 Below  
2024-08-11 58.97 Below  
2024-08-10 58.98 Below  
2024-08-09 58.94 Below  
2024-08-08 58.82 Below  
2024-08-07 58.59 Below  
2024-08-06 58.68 Below  
2024-08-05 58.93 Below  
2024-08-04 59.36 Below  
2024-08-03 58.00 Below  
2024-08-02 58.99 Below  
2024-08-01 59.25 Below  
2024-07-31 58.73 Below  
2024-07-30 58.77 Below  
2024-07-29 58.44 Below  
2024-07-28 57.98 Below  
2024-07-27 58.12 Below  
2024-07-26 58.58 Below  
2024-07-25 58.40 Below  
2024-07-24 58.97 Below  
2024-07-23 58.81 Below  
2024-07-22 58.72 Below  
2024-07-21 58.73 Below  
2024-07-20 58.70 Below  
2024-07-19 58.29 Below  
2024-07-18 57.87 Below  
2024-07-17 57.36 Below  
2024-07-16 57.91 Below  
2024-07-15 57.79 Below  
2024-07-14 57.43 Below  
2024-07-13 57.83 Below  
2024-07-12 57.88 Below  
2024-07-11 57.93 Below  
2024-07-10 57.98 Below  
2024-07-09 57.87 Below  
2024-07-08 57.75 Below  
2024-07-07 57.71 Below  
2024-07-06 57.83 Below  
2024-07-05 57.68 Below  
2024-07-04 57.63 Below  
2024-07-03 57.76 Below  
2024-07-02 58.43 Below  
2024-07-01 58.59 Below  
2024-06-30 58.42 Below  
2024-06-29 58.11 Below  
2024-06-28 57.78 Below  
2024-06-27 57.30 Below  
2024-06-26 57.95 Below  
2024-06-25 56.82 Below  
2024-06-24 57.45 Below  
2024-06-23 57.12 Below  
2024-06-22 57.06 Below  
2024-06-21 56.49 Below  
2024-06-20 55.50 Below  
2024-06-19 55.19 Below  
2024-06-18 54.13 Below  
2024-06-17 53.26 Below  
2024-06-16 53.15 Below  
2024-06-15 53.23 Below  
2024-06-14 54.35 Below  
2024-06-13 57.01 Below  
2024-06-12 58.08 Below  
2024-06-11 57.76 Below  
2024-06-10 57.79 Below  
2024-06-09 57.71 Below  
2024-06-08 57.90 Below  
2024-06-07 58.08 Below  
2024-06-06 57.93 Below  
2024-06-05 57.81 Below  
2024-06-04 56.80 Below  
2024-06-03 55.95 Below  
2024-06-02 55.70 Below  
2024-06-01 55.63 Below  
2024-05-31 55.50    
2024-05-30 55.17    
2024-05-29 55.39    
2024-05-28 55.00    
2024-05-27 54.84    
2024-05-26 54.28    
2024-05-25 53.50    
2024-05-24 53.91    
2024-05-23 53.58    
2024-05-22 53.47    
2024-05-21 52.66    
2024-05-20 52.11    
2024-05-19 52.05    
2024-05-18 52.37    
2024-05-17 53.46    
2024-05-16 54.51    
2024-05-15 54.98    
2024-05-14 54.83    
2024-05-13 54.78    
2024-05-12 54.65    
2024-05-11 54.39    
2024-05-10 54.10    
2024-05-09 53.74    
2024-05-08 52.80    
2024-05-07 52.49    
2024-05-06 51.67    
2024-05-05 51.38    
2024-05-04 51.72    
2024-05-03 52.97    
2024-05-02 52.41    
2024-05-01 52.44    
2024-04-30 52.30    
2024-04-29 52.45    
2024-04-28 52.93    
2024-04-27 52.36    
2024-04-26 52.46    
2024-04-25 52.20    
2024-04-24 53.38    
2024-04-23 52.96    
2024-04-22 53.43    
2024-04-21 53.53    
2024-04-20 53.32    
2024-04-19 53.19    
2024-04-18 52.64    
2024-04-17 52.58    
2024-04-16 52.31    
2024-04-15 51.75    
2024-04-14 49.62    
2024-04-13 50.67    
2024-04-12 51.85    
2024-04-11 53.28    
2024-04-10 52.61    
2024-04-09 52.23    
2024-04-08 51.05    
2024-04-07 50.80    
2024-04-06 49.33    
2024-04-05 49.46    
2024-04-04 49.45    
2024-04-03 51.33    
2024-04-02 52.09    
2024-04-01 51.01    
2024-03-31 50.22    
2024-03-30 49.69    
2024-03-29 49.17    
2024-03-28 49.59    
2024-03-27 49.43    
2024-03-26 49.63    
2024-03-25 49.64    
2024-03-24 49.49    
2024-03-23 49.16    
2024-03-22 49.25    
2024-03-21 49.57    
2024-03-20 51.14    
2024-03-19 51.09    
2024-03-18 50.75    
2024-03-17 50.45    
2024-03-16 50.10    
2024-03-15 49.78    
2024-03-14 49.28    
2024-03-13 49.29    
2024-03-12 49.49    
2024-03-11 48.68    
2024-03-10 48.72    
2024-03-09 48.83    
2024-03-08 48.94    
2024-03-07 49.15    
2024-03-06 49.93    
2024-03-05 48.37    
2024-03-04 46.94    
2024-03-03 46.84    
2024-03-02 47.08    
2024-03-01 48.53    
2024-02-29 49.40    
2024-02-28 49.17    
2024-02-27 48.68    
2024-02-26 49.78    
2024-02-25 50.32    
2024-02-24 50.29    
2024-02-23 50.00    
2024-02-22 49.58    
2024-02-21 49.40    
2024-02-20 51.00    
2024-02-19 51.33    
2024-02-18 50.75    
2024-02-17 49.75    
2024-02-16 50.00    
2024-02-15 49.39    
2024-02-14 48.52    
2024-02-13 48.57    
2024-02-12 47.95    
2024-02-11 47.82    
2024-02-10 47.80    
2024-02-09 47.97    
2024-02-08 47.90    
2024-02-07 48.42    
2024-02-06 49.91    
2024-02-05 50.06    
2024-02-04 47.97    
2024-02-03 48.38    
2024-02-02 50.19    
2024-02-01 50.66    
2024-01-31 49.75    
2024-01-30 50.31    
2024-01-29 50.18    
2024-01-28 50.60    
2024-01-27 50.19    
2024-01-26 49.67    
2024-01-25 49.53    
2024-01-24 50.52    
2024-01-23 50.20    
2024-01-22 51.21    
2024-01-21 50.18    
2024-01-20 49.34    
2024-01-19 47.95    
2024-01-18 47.84    
2024-01-17 47.84    
2024-01-16 46.69    
2024-01-15 47.26    
2024-01-14 47.75    
2024-01-13 46.08    
2024-01-12 46.86    
2024-01-11 46.63    
2024-01-10 47.56    
2024-01-09 48.17    
2024-01-08 47.88    
2024-01-07 47.12    
2024-01-06 48.06    
2024-01-05 49.02    
2024-01-04 48.95    
2024-01-03 49.14    
2024-01-02 48.84    
2024-01-01 49.25    

Data Methods and Notes

Data Methods

  1. Data Courtesy of CDEC and US Geological Survey
  2. Hourly data for Clear Creek nr Igo (IGO) is retrieved from CDEC on a daily basis.
  3. Columbia Basin Research (CBR) QA/QC process on IGO hourly data for outliers, false data (e.g., 32°F measured by satellite), and data outside expected range of observation (e.g., 90°F). Data loaded into CBR database.
  4. CBR calculates Daily Average values based on CBR cleaned hourly values.
  5. Query for daily average water temperature for selected year.
  6. Examine daily average data for 60°F and 56°F exceedance during date periods as outlined in Reclamation Proposed Action.

Thresholds

Please refer to the Clear Creek Technical Team (CCTT) annual reports for details on within water year activities.

Target analysis and exceedance found on this page is based on criteria as described in Reclamation 2019, p4-2.

Reclamation 2019. Reinitiation of Consultation on the Coordinated Long-Term Operation of the Central Valley Project and State Water Project Central Valley Project, California Mid-Pacific Region, Final Biological Assessment, Chapter 4: Proposed Action. October 21. Available online: https://www.usbr.gov/mp/bdo/lto/biop.html

Daily water temperature in below normal and wetter years of: (1) 60°F at the Igo gage from June 1 through September 15; and (2) 56°F or less at the Igo gage from September 15 to October 31; operate as close as possible to these targets in dry and critical years.