The CSI depicts the response to monthly (and longer) precipitation and streamflow conditions rather than hourly to daily fluctuations. The maps and graphs on this page show the latest real-time trends in salinity, water temperature, and gage height at the CSI sites.

Select a variable and time interval to view average salinity, water temperature, or gage-height over the past 7 days, 14 days, 1 month, 2 months, or 3 months. By averaging over these time intervals, the graphed results are more indicative of recent trends in salinity, temperature, and gage height than current hourly or daily conditions.

Gage height is the height of water in the stream above a constant reference point. For the purposes of this website, gage-height record that has not been converted to a unified datum is limited to a single location and specific reference point as setup by the managing agency. Any change in location or reference point position would therefore disrupt the continuity of the gage-height measurements.

"Change" variables represent the difference between the average value of data over the most recent time interval and the average value of data over the previous time interval.

Click the sites on the map for links to data and graphs.

Explanation
Data:   
Time Interval:   

  • ≤ 0.5 PSU
  • 0.6 - 2.9 PSU
  • 3.0 - 6.9 PSU
  • 7.0 - 11.9 PSU
  • 12.0 - 17.9 PSU
  • 18.0 - 29.9 PSU
  • ≥ 30.0 PSU
  • Data Not Available

  • Practical Salinity Units (PSU)

  • ≤ -2 PSU
  • -1.9 to -1.0 PSU
  • -0.9 to 0 PSU
  • 0 PSU
  • 0.1 to 1.0 PSU
  • 1.1 to 2.0 PSU
  • 2.1 to 3.0 PSU
  • ≥ 3.1 PSU
  • Not Available

  • Practical Salinity Units (PSU)
  • ≤ 9.9 °C
  • 10.0 - 13.9 °C
  • 14.0 - 17.9 °C
  • 18.0 - 21.9 °C
  • 22.0 - 25.9 °C
  • 26.0 - 29.9 °C
  • ≥ 30.0 °C
  • Not Available

  • Degrees Celsius (°C)
  • ≤ 49.9 °F
  • 50.0 - 57.9 °F
  • 58.0 - 64.9 °F
  • 65.0 - 71.9 °F
  • 72.0 - 78.9 °F
  • 79.0 - 85.9 °F
  • ≥ 86.0 °F
  • Not Available

  • Degrees Celsius (°F)
  • ≤ -2 °C
  • -1.9 to -1.0 °C
  • -0.9 to 0 °C
  • 0 °C
  • 0.1 to 1.0 °C
  • 1.1 to 2.0 °C
  • 2.1 to 3.0 °C
  • ≥ 3.1 °C
  • Not Available

  • Degrees Celsius (°C)

  • ≤ -4.00 °F
  • -3.99 to -2.00 °F
  • -1.99 to -0.01 °F
  • 0 °F
  • 0.01 to 1.99 °F
  • 2.00 to 3.99 °F
  • ≥ 4.00 °F
  • Not Available

  • Degrees Fahrenheit (°F)

  • Lowest value on record
  • < 10 percentile
  • 10 - 24 percentile
  • 25 - 75 percentile
  • 76 - 90 percentile
  • > 90 percentile
  • Highest value on record
  • Not Available

  • Values are compared to values
    on the same dates of other years.
  • ≤ -2.00 ft
  • -1.99 to -1.00 ft
  • -0.99 to 0.00 ft
  • 0.00 ft
  • 0.01 to 1.00 ft
  • 1.01 to 2.00 ft
  • 2.01 to 3.00 ft
  • ≥ 3.01 ft
  • Not Available

  • Datum is specific to each gage
  • ≤ -0.60 m
  • -0.59 to -0.30 m
  • -0.29 to 0.00 m
  • 0.00 m
  • 0.01 to 0.30 m
  • 0.29 to 0.60 m
  • 0.59 to 1.00 m
  • ≥ 1.01 m
  • Not Available

  • (Datum is specific to each gage)

Operating Agency
  • U.S. Geological Survey (USGS)
  • National Estuarine Research Reserves (NERRS)
  • National Park Service (NPS)
"Change" variables represent the difference between the average value of data over the most recent time interval and the average value of data over the previous time interval.

Gage height is the height of water in the stream above a constant reference point. For the purposes of this website, gage-height record that has not been converted to a unified datum is limited to a single location and specific reference point as setup by the managing agency. Any change in location or reference point position would therefore disrupt the continuity of the gage-height measurements.