Combining estimates of low-flow characteristics of streams in Massachusetts and Rhode Island

Gary D. Tasker

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Combining estimates of low-flow characteristics of streams in Massachusetts and Rhode Island

Gary D. Tasker

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Abstract

The number of base-flow measurements needed to meet specified accuracy goals for estimating low-flow characteristics at ungaged sites can be reduced by combining an estimate based on a regression of base-flow measurements on discharges from a nearby continuous long-term gaging station with an estimate based on a regional relationship developed from regressing the low-flow characteristics on basin characteristics. The estimates should be combined by weighting each inversely with its variance from the true value. Empirically estimated values of variance of the estimated 7- day, 10-year low flow from its true value indicate that more than six or eight base-flow measurements add" little to the confidence with which such an estimate is made.

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Journal of Research of the U.S. Geological Survey Article

Source-reported bounding extent: 41.146339° to 42.886589° latitude; -73.508142° to -69.928261° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Gary D. Tasker. 1975. Combining estimates of low-flow characteristics of streams in Massachusetts and Rhode Island. https://pubs.usgs.gov/publication/70232675

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