Columbia Basin Performance Measures

Methods and Explanation of Summary Table Fields

Query Parameters

YearYear as specified in the query.
ProjectProject as specified in the query.
River ParameterRiver Parameter as specified in the query.
Critical ValueCritical Value or range of Critical Values as specified in the query.
Calculate Exposure Below Critical Value: Calculate the percent of fish exposed to values below the selected Critical Value for the selected River Parameter.
Above Critical Value: Calculate the percent of fish exposed to values above the selected Critical Value for the selected River Parameter.
Range Critical Value: Calculate the percent of fish exposed to values within the range of Critical Values for the selected River Parameter.
Fill Missing River DataYes: Apply simple data interpolation to fill missing data points within the River Parameter data set. These filled values will be used in calculations for fish exposure and averages.
No: Use River Parameter data set as found in DART.

Total Run Period

The Total Run Period is defined by the first date when fish are observed/transported to the last date when fish are observed/transported at the selected Project within the selected Start and End dates. The values for Start Date and End Date specified in the query determine the maximum length of the run period. The Total Run Period may not reflect the true run period.

Total Number of Fish Observed/Transported

Total number of fish observed/transported during the Total Run period.

In the case of Transport queries, this is the total number of fish transported (the sum of the number of fish barged and trucked from the project).

Percent of Total Run Analyzed [Number Observed/Transported]

Percent of the total number of fish observed/transported that qualify to be analyzed (the number of fish analyzed follows in square brackets).

In order for observed/transported fish to be included in the analysis, River Parameter data must be available for the same day. If River Parameter data is unavailable/missing for any day during the Total Run Period, then the number of fish analyzed is less than the number of fish observed/transported.

Exposure Index exposure index equation
  • Fishj = The number of fish observed/transported on a day j.
  • RiverValuej = The observed value for the River Parameter on day j.
  • TotalFish = The number of fish observed/transported at the selected Project during the Total Run period.
  • firstDay = First day of the Total Run period.
  • lastDay = Last day of the Total Run period.

Total Percent Fish Exposed [Number Exposed]

The number of fish exposed divided by the Total Number of Fish Analyzed observed/transported at the Project during the Total Run Period. The number of fish exposed follows in square brackets.

The Number Exposed is based on the query specification for whether exposure is calculated below the Critical Value, above the Critical Value or within a range of Critical Values.

  • Below = the sum of the fish observed/transported at the Project on days when the River Parameter value observed on that day is less than or equal to Critical Value selected.
  • Above = the sum of the fish observed/transported at the Project on days when the River Parameter value observed on that day is greater than or equal to Critical Value selected.
  • Range = the sum of the fish observed/transported at the Project on days when the River Parameter value observed on that day is greather than or equal to the Low Critical Value selected and less than the High Critical Value selected.
Number of Days Fish Exposed Total number of days when fish are observed/transported at the Project and the River Parameter value observed matches the critical value conditions as defined in the number of fish exposed.

Middle 80% of Run Period

The Middle 80% of the Run is defined by a range of days rather than an exact percent of the run. The Middle 80% of the Run Period begins on the first day when the percent of fish observed/transported at the Project is greater than or equal to 10%. The Middle 80% of the Run Period ends on the first day when the percent of fish observed/transported at the Project is greater than or equal to 90%. In some cases, the percent of the run passing during this period can be well above 80%.

Number of Fish Observed/TransportedThe total number of fish observed/transported at the selected Project during the Middle 80% of the Run Period.
Percent of Middle 80% of Run Analyzed [Number Observed/Transported]

Percent of the total number of fish observed/transported during the Middle 80% of the Run Period that qualify to be analyzed (the number of fish analyzed follows in square brackets).

In order for observed/transported fish to be included in the analysis, River Parameter data must be available for the same day. If River Parameter data is unavailable/missing for any day during the Middle 80% of the Run Period, then the number of fish analyzed is less than the number of fish observed/transported.

Exposure Indexexposure index equation
  • Fishj = The number of fish observed/transported on a day j.
  • RiverValuej = The observed value for the River Parameter on day j.
  • TotalFish = The total number of fish observed/transported at the selected Project during the Middle 80% of the Run period.
  • firstDay = First day of the Middle 80% of the Run period.
  • lastDay = Last day of the Middle 80% of the Run period.

Percent Fish Exposed [Number Exposed]

The number of fish exposed divided by the Number of Fish Analyzed observed/transported at the Project during the Middle 80% of the Run period. The number of fish exposed during the Middle 80% of the Run period follows in square brackets.

The Number Exposed is based on the query specification for whether exposure is calculated below the Critical Value, above the Critical Value or within a range of Critical Values.

  • Below = the sum of the fish observed/transported at the Project on days when the River Parameter value observed on that day is less than or equal to Critical Value selected.
  • Above = the sum of the fish observed/transported at the Project on days when the River Parameter value observed on that day is greater than or equal to Critical Value selected.
  • Range = the sum of the fish observed/transported at the Project on days when the River Parameter value observed on that day is greather than or equal to the Low Critical Value selected and less than the High Critical Value selected.
Number of Days Fish Exposed The number of days during the Middle 80% of the Run period when fish are observed/transported at the Project and the River Parameter value observed matches the critical value conditions as defined in the number of fish exposed.

Run Dates

Run Dates are based on the Total Run Period of the query. The Total Run Period may not reflect the true run period.

First Day of RunDate of the first day of the run.
5% of Run passedDate when the percent of fish passing the Project is greater than or equal to 5%.
10% of Run passedDate when the percent of fish passing the Project is greater than or equal to 10%.
50% of Run passedDate when the percent of fish passing the Project is greater than or equal to 50%.
90% of Run passedDate when the percent of fish passing the Project is greater than or equal to 90%.
95% of Run passedDate when the percent of fish passing the Project is greater than or equal to 95%.
Last Day of RunDate of the last day of the run.

Date(s) When River Parameter Crosses Critical Value Line/Range

For a single Critical Value, the dates when the observed value for the River Parameter is equal to the Critical Value, and dates when the observed value for the River Parameter crosses below or above the Critical Value line. For a range of Critical Values, the dates when the observed value for the River Parameter crosses inside or outside of the specified Critical Value range.

River Environment Glossary

Barometric Pressure
Barometric Pressure is atmospheric pressure at the site, given in mm Hg. It represents an average of hourly measures. Barometric Pressure is measured at Water Quality Monitoring stations in the forebay and tailrace of most projects (see Data Sites Map) and other key locations in the basin. Prior to 1995, the data are from a variety of sources within the U.S. Army Corps of Engineers.
Dissolved Gas
Dissolved gas is a measure of the pressure of dissolved gas in the water column. When spillway water plunges into the tailrace nitrogen is forced into the water at higher than normal levels. This condition, called supersaturation, occurs when dissolved gas pressure in the water actually exceeds the atmospheric pressure. The dissolved gas value represents a daily average of hourly meeasures within the range of 600-900 mmHg and is derived from U.S. Army Corps of Engineers gas monitoring efforts. Often collected at irregular intervals, this parameter may be missing values for one or more days, or reported values may be obviously incorrect. Dissolved Gas is measured at Water Quality Monitoring stations in the forebay and tailrace of most projects (see Data Sites Map) and other key locations in the basin. Prior to 1995, the data are from a variety of sources within the U.S. Army Corps of Engineers.
Dissolved Gas Percent
Gas percent reflects the degree of total dissolved gas supersaturation in the river at the given location. Gas percent is the daily mean of hourly observations. When gas pressure is exactly the same as the atmospheric pressure, the water is considered to be 100% saturated. If the gas pressure value is higher than atmospheric pressure, gas percent values rise above 100%. Daily averages are calculated from hourly values within the range of 90% to 200%. Gas percent data is often found to be quite noisy due to rapid fluctuations in spill volumes and atmospheric pressures. Dissolved Gas Percent is measured at Water Quality Monitoring stations in the forebay and tailrace of most projects (see Data Sites Map) and other key locations in the basin. Prior to 1995, the data are from a variety of sources within the U.S. Army Corps of Engineers.
Elevation
Elevation is given in feet above mean sea level and is a daily average of hourly measures. At most sites this will change less than a fraction of a foot over normal operations. Elevation is measured in the forebay of a project.
Elevation 10 Year Average
Daily average of elevation for a selected 10 year range. For each month and day, the data is summed for the selected 10 years and divided by the number of non-null data points available during that 10 year span.
Inflow
Inflow measurements represent the 24-hour average of hourly measures, reported by the U.S. Army Corps of Engineers. Inflow is given in kcfs, thousands of cubic feet per second.
Outflow
Outflow measurements represent the 24-hour average of hourly measures, reported by the U.S. Army Corps of Engineers. Outflow is given in kcfs, thousands of cubic feet per second. This represents the total outflow at any project, including spill and fish ladder flow.
Outflow 10 Year Average
Daily average of outflow for a selected 10 year range. For each month and day, the data is summed for the selected 10 years and divided by the number of non-null data points available during that 10 year span.
Spill
Spill also is given as a daily average of 24 hourly measures taken by the U.S. Army Corps of Engineers. It is also given in kcfs.
Spill 10 Year Average
Daily average of spill for a selected 10 year range. For each month and day, the data is summed for the selected 10 years and divided by the number of non-null data points available during that 10 year span.
Spill Percent
Spill Percent is calculated by DART from the daily averaged value for Spill divided by the daily averaged value for Outflow at a project.
Temperature (Scroll Case)
Temperature (Scroll Case) is water temperature in degrees Celsius. This data is measured at the scroll case (part of the powerhouse) at a project. If provided values are in Fahrenheit, they are converted to Celsius. Temperature records are typically not collected outside the salmon migration season, so they are not usually 365 days long. Values above 0 C and below 35 C are averaged for a daily value.
Temperature (Scroll Case) 10 Year Average
Daily average of scroll case temperature for a selected 10 year range. For each month and day, the data is summed for the selected 10 years and divided by the number of non-null data points available during that 10 year span.
Temperature (WQM)
Temperature (WQM) is water temperature in degrees Celsius. This data is measured at Water Quality Monitoring stations in the forebay and tailrace of most projects (see Data Sites Map) and other key locations in the basin. Temperature records are typically not collected outside the salmon migration season, so they are not usually 365 days long. Daily averages are calculated from hourly values above 0 C and below 35 C. Temperature at water quality monitoring stations was not collected prior to 1995.
Temperature (WQM) 10 Year Average
Daily average of water quality monitor temperature for a selected 10 year range. For each month and day, the data is summed for the selected 10 years and divided by the number of non-null data points available during that 10 year span.
Turbidity
Turbidity measures the water clarity, and by inference, the amount of particulate matter present. Turbidity is measured in the forebay or in the fish ladders of a project. Turbidity is reported in feet and measured with a Secchi Disk. In general, the Secchi disk is a 20 cm circular black and white plate. The Secchi disk is attached to a calibrated line and lowered into the water to the depth at which it disappears. The disk is then lifted until it reappears. The arithmetic mean of the two depths is considered the Secchi disk transparency or limit of visibility.