Connecticut StreamStats

StreamStats for Connecticut can be used to estimate flood discharges with annual exceedance probabilities of 50-, 20-, 10-, 4-, 2-, 1-, 0.5-. and 0.2-percent for ungaged, unregulated or slightly regulated streams in Connecticut. These exceedance probabilities correspond to recurrence intervals of 2-, 5-, 10-, 25-, 50-, 100-, 200-, and 500-years, respectively.   

StreamStats for Connecticut also can be used to estimate flow-duration statistics with flow exceedances ranging from 25 to 99 percent for six “bioperiods”—Salmonid Spawning (November), Overwinter (December–February), Habitat Forming (March–April), Clupeid Spawning (May), Resident Spawning (June), and Rearing and Growth (July–October); and to estimate the 25- and 99-percent flow exceedances without reference to a bioperiod.  

General information and documentation of methods used to develop the regression equations and to measure the basin characteristics used in the equations, and the errors associated with the estimates obtained from the equations can be found the reports listed below. Users should familiarize themselves with these reports before using StreamStats to obtain estimates of flows for ungaged sites.

• Ahearn, E.A., and Hodgkins, G.A., 2020, Estimating flood magnitude and frequency on streams and rivers in Connecticut, based on data through water year 2015: U.S. Geological Survey Scientific Investigations Report 2020–5054, 42 p., https://doi.org/10.3133/sir20205054.
• Ahearn, E.A., 2010, Regional regression equations to estimate flow-duration statistics at ungaged stream sites in Connecticut: U.S. Geological Survey Scientific Investigations Report 2010–5052, 45 p.

A worksheet for computing annual prediction intervals, not available through the USGS StreamStats web application for flood discharges can be downloaded here:

•  https://www.sciencebase.gov/catalog/item/5e7e6ed3e4b01d5092771850 

Click on this link to obtain general information on the flood discharge and flow-duration equations for the Connecticut application, as well as specific sources for basin and climatic characteristics in the equations.   
 

Streamflow and Sustainable Water Use Estimator used with StreamStats

The Connecticut Streamflow and Sustainable Water Use Estimator (CTSSUEE) was developed to be used in conjunction with the Connecticut StreamStats application to estimate daily unaltered and water-use adjusted streamflow at ungaged locations in Connecticut for the period of October 1, 1960 to September 30, 2014.  Basin delineations, basin characteristics, and aggregated water use information for the period of 2010-2014 can be obtained in the Connecticut Streamstats application and imported into the CTSSUE software. General information and documentation of methods used in the CTSSUEE can be found at the following links:

• Connecticut Streamflow and Sustainable Water Use Estimator
• Levin, S.B., Olson, S.A., Nielsen, M.G., and Granato, G.E., 2018, The Connecticut Streamflow and Sustainable Water Use Estimator—A decision-support tool to estimate water availability at ungaged stream locations in Connecticut: U.S. Geological Survey Scientific Investigations Report 2018–5135, 34 p., https://doi.org/10.3133/sir20185135.

The CTSSUE software can be downloaded here:

 https://www.sciencebase.gov/catalog/item/5b7998b1e4b0f5d578845498

Click on this link to obtain general information on the CTSSUE application, as well as specific sources and computation methods for basin characteristics.