Estimation of low-flow duration discharges in Massachusetts

Equations for estimating the 95-, 98-, and 99-percent duration discharges for streams in Massachusetts with natural flow conditions were developed by use of weighted-least-squares regression analyses. Record extension methods were used to estimate the low-flow statistics for sites used in the regression analyses that were lacking complete record during the base period of October 1, 1962 through September 30, 1987. Basin characteristics used as independent variables in the regression analyses were measured by use of a computerized geographic information system. The equations were used to estimate the duration discharges for 72 selected sites in eastern Massachusetts.