Estimating Mean Runoff in Ungaged Semiarid Areas

Abstract

Relations of runoff to altitude may be defined for a hydrologically homogeneous region by using a limited number of streamflow records. Mean runoff from ungaged basins in this same region can then be computed on the basis of this derived relation. When these relations of runoff to altitude are applied to small areas, the runoff may be different from that indicated by the relation, because oflocal differences in geology, precipitation, vegetation, land slopes, and land use. Two methods are described for adjusting the relations for the effects of these variations; one based on a streamflow measurement at miscellaneous sites which is applicable to perennial streams, the other on measurement of two channel parameters which is applicable to either perennial or ephemeral streams.

Channel Restoration Design for Meandering Rivers

“…Using similar techniques to hydraulic geometry, 'channel geometry' equations are developed from data pertaining to natural channel systems by relating stream flow data from gauging stations to river channel dimensions measured in the vicinity of those stations using regression techniques (Wharton, 1995a, p. 650). Using channel geometry as a modification of the hydraulic geometry concept was first proposed by Moore (1968) in Nevada and later developed by Hedman (1970) for California streams. The equations take the form of power functions and generally relate discharge of some statistical frequency to either width or crosssectional area, measured at a specified geomorphic reference stage (Wharton, 1995a).…”

Calibration of a mathematical model of the Antelope Valley ground-water basin, California

“…Although the channel geometry is influenced by the channel slope and pattern, sediment loads, cohesiveness of the banks, and vegetation, studies by Moore (1968) indicate that the dimensions of cross sections at the bars and berms are not significantly affected by these factors and that the dimensions of cross sections are related to the mean annual runoff. Using the width (W) and depth (D) in feet at bars and berms, Hedman (1970) developed, from southern California streamflow data, the empirical relation Q = 258 W°-80 D°-60 (2) for estimating the mean annual discharge (Q) in acre-feet.…”

“…An alluvial channel adjusts in size to accommodate the discharge it receives (Moore, 1968;Leopold and Wolman, 1957). Although the channel geometry is influenced by the channel slope and pattern, sediment loads, cohesiveness of the banks, and vegetation, studies by Moore (1968) indicate that the dimensions of cross sections at the bars and berms are not significantly affected by these factors and that the dimensions of cross sections are related to the mean annual runoff.…”

Water-resources appraisal of the Carson River basin, western Nevada

“…Table 14 summarizes the estimated runoff from tributary streams for the four mainstem hydrographic areas. Moore (1968).…”

“…Where stream-gaging records were not available, the ungaged runoff from tributary streams was estimated using the indirect methods developed by Moore (1968). The relationship between altitude, precipitation, and average annual .runoff was defined for each hydrpgraphic area at the mountain front.…”