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Regional regression equations were calculated in Puerto Rico with generalized least squares techniques to estimate flood frequency statistics at ungaged locations using drainage area as the only explanatory variable. The island was divided into 2 regions to minimize residuals. The region division that resulted in lower and more balanced residuals runs primarily north-south near the center of the island, mostly along an 8-digit hydrologic unit code (HUC8) boundary. The division line runs through a HUC8 polygon on the southern end of the island, but care was taken to include entire watersheds and consideration was given where hydrologic and physiographic properties differed. This data release includes geographic information...
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Discharge through 13 water control structures in Florida was calculated using theoretical equations and coefficients and compared to USGS-published discharge from October 1, 2007 to September 30, 2019. The two daily mean discharges were not compared for any values below 10 cubic feet per second or if (1) any alterations were made to the published discharge to account for factors such as debris or construction; (2) any values were missing throughout the day; (3) the flow regime changed during the day; or (4) the published discharge was estimated. The structures compared include a mixture of sluice and radial gates with free and submerged conditions for orifice and weir flow. The theoretical discharges, published...
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The magnitude and frequency of floods at 91 rural, unregulated streamgages in Puerto Rico were updated using annual peak-flows through 2017. The USGS program PeakFQ version 7.3 (U.S. Geological Survey, 2019) was used to estimate the parameters of the Log-Pearson Type III distribution using updated methods outlined in Bulletin 17C (England and others, 2018) and regional skew of 0.28 and a mean-squared error of 0.20. This data release includes (1) a spreadsheet file showing streamgage information, perception thresholds, and intervals used in PeakFQ; (2) raw input files (.txt) and spec file (.psf) loaded into PeakFQ; and (3) output files (.PRT) from PeakFQ showing the magnitude and frequency peak-flow estimates, as...
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Estimates of the magnitude of peak-flows were updated for the 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent chance exceedance levels for 91 rural, unregulated streamgaging stations on the main island of Puerto Rico. These stations required 10 or more years of annual peak-flow record, using data to 2017, for inclusion in the study. The magnitude and frequency of floods at selected streamgages in Puerto Rico were estimated using the U.S. Geological Survey PeakFQ program and updated methods outlined in Bulletin 17C (England and others, 2018). Regional regression equations were calculated to estimate flood frequency statistics at ungaged locations using selected basin characteristics as explanatory variables. These...
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Generalized least squares (GLS) techniques were used with at-site statistics, from PeakFQ, and drainage area for streamgages in Puerto Rico to calculate regional regression equations for ungaged locations. The GLS approach assigns weights based on uncertainty of the observations (ie. record length and variance) and accounts for correlated streamflows and time-sampling errors (Farmer and others, 2019). Two separate regions were defined for the use of these equations to minimize residuals, and performance metrics from WREG were analyzed to determine drainage area as the only explanatory variable provided the best results. Values for the correlation smoothing function in region 1 were alpha equal to 0.006 and theta...
    map background search result map search result map Data Files for the Development of Regression Equations for the Estimation of the Magnitude and Frequency of Floods at Rural, Unregulated Gaged and Ungaged Streams in Puerto Rico through Water Year 2017 (ver. 1.1, September 2021) At-site Flood Frequency PeakFQ Estimates in Puerto Rico Through Water Year 2017 Puerto Rico Generalized Least Squares WREG Regression Files Regions for regional regression equations Data for the Comparison of Computed Flow Through Manually Operated Water Control Structures in Florida Using Theoretical Versus Calibrated Coefficients Regions for regional regression equations Data Files for the Development of Regression Equations for the Estimation of the Magnitude and Frequency of Floods at Rural, Unregulated Gaged and Ungaged Streams in Puerto Rico through Water Year 2017 (ver. 1.1, September 2021) At-site Flood Frequency PeakFQ Estimates in Puerto Rico Through Water Year 2017 Puerto Rico Generalized Least Squares WREG Regression Files Data for the Comparison of Computed Flow Through Manually Operated Water Control Structures in Florida Using Theoretical Versus Calibrated Coefficients