do.usbr. Summary We investigate the applicability of the Two-dimensional, Runoff, Erosion and Export (TREX) model to simulate extreme floods on large watersheds in semi-arid regions in the western United States. Spatially-distributed extreme storm and channel components are implemented so that the TREX model can be applied to this problem. TREX is demonstrated via calibration, validation and si...

Design hydrographs are important for the design of hydraulic structures such as spillways and retention ponds. Due to the lack of the local data, engineers have to estimate design floods based on techniques which are able to predict runoff based on rainfall on a regional basis. In this study, Clark instantaneous unit hydrographs are used to predict design flood hydrographs for the selected catc...

Hydrograph recession constants are required in rainfall-runoff models, base flow augmentation studies, geohydrologic investigations and in regional low-flow studies. The recession portion of a streamflow hydrograph is shown to be either an autoregressive process or an integrated moving average process, depending upon the structure of the assumed model errors. Six different estimators of the bas...

Most models will attempt to extract losses (interception, surface storage, infiltration) from the input and build a runoff hydrograph using empirical curves or by routing the excess water. Even the simplest models generally involve many parameters to describe these processes. Some parameters are estimated from published values, and others are set based on past practice and calibration of the mo...

A method for estimation of mean baseflow residence time in watersheds from hydrograph runoff recession characteristics was developed. Runoff recession characteristics were computed for the period 1993–96 in the 2 km2 Winnisook watershed, Catskill Mountains, southeastern New York, and were used to derive mean values of subsurface hydraulic conductivity and the storage coefficient. These values w...

This paper develops a new routing algorithm for improving simulation capacity of physically-based hydrological models applied to sparsely-gauged river basins. The study area is the Lhasa River basin, a large plateau basin with an area of 26,225 km2 in southwest China. In the basin, observations from three hydrological stations are available, and the observed hourly rainfall and summer stream fl...

Determination of maximum rivers flow resulted from surface runoff in watersheds without adequate hydrometric records is based on rainfall-runoff models. The short duration rainfalls are one of the basic elements to apply these models. The access to quantitative and intrinsic worth storm data is restricted around the word and in Iran too. There are several empirical and statistical methods to es...