Enhancement of Duration Curve Prediction Using Short Time Low Flow Measurements

摘要

An analysis is presented of the year-to-year and day-to-day variation of low-flow stream discharge used in small-scale hydroelectric power projects. Primary use was made of flow duration procedures. Past streamflow gaging records were used to evaluate the variation over time as well as the variation of simultaneous measurements at different sites. Methodologies were developed for determining the low flow percentage exceedance values at an ungaged site using a single streamflow measurement coupled with knowing the exceedance percentages at gaged streamflow sites in the area. A major contribution of this methodology is a means of estimating the confidence bounds of the estimates made. The report also includes a number of field measurements of unregulated streams in northern Idaho for which interest in hydropower development has been shown or where streams were thought to be indicators of smaller basin behavior.