DSpace Repository

Derivation and verification of empirical catchment response time equations for medium to large catchments in South Africa

Show simple item record

dc.contributor.author Gericke, O. J.
dc.contributor.author Smithers, J. C.
dc.date.accessioned 2018-08-08T10:27:42Z
dc.date.available 2018-08-08T10:27:42Z
dc.date.issued 2016
dc.identifier.issn 1099-1085
dc.identifier.issn 0885-6087
dc.identifier.uri http://hdl.handle.net/11462/1478
dc.description Published Article en_US
dc.description.abstract Despite uncertainties and errors in measurement, observed peak discharges are the best estimate of the true peak discharge from a catchment. However, in ungauged catchments, the catchment response time is a fundamental input to all methods of estimating peak discharges; hence, errors in estimated catchment response time directly impact on estimated peak discharges. In South Africa, this is particularly the case in ungauged medium to large catchments where practitioners are limited to use empirical methods that were calibrated on small catchments not located in South Africa. The time to peak (TP), time of concentration (TC) and lag time (TL) are internationally the most frequently used catchment response time parameters and are normally estimated using either hydraulic or empirical methods. Almost 95% of all the time parameter estimation methods developed internationally are empirically based. This paper presents the derivation and verification of empirical TP equations in a pilot scale study using 74 catchments located in four climatologically different regions of South Africa, with catchment areas ranging from 20 km2 to 35 000 km2. The objective is to develop unique relationships between observed TP values and key climatological and geomorphological catchment predictor variables in order to estimate catchment TP values at ungauged catchments. The results show that the derived empirical TP equation(s) meet the requirement of consistency and ease of application. Independent verification tests confirmed the consistency, while the statistically significant independent predictor variables included in the regressions provide a good estimation of catchment response times and are also easy to determine by practitioners when required for future applications in ungauged catchments. It is recommended that the methodology used in this study should be expanded to other catchments to enable the development of a regional approach to improve estimation of time parameters on a national-scale. However, such a national-scale application would not only increase the confidence in using the suggested methodology and equation(s) in South Africa, but also highlights that a similar approach could be adopted internationally. en_US
dc.format.extent 1 249 580 bytes, 1 file
dc.format.mimetype Application/PDF
dc.language.iso en_US en_US
dc.publisher HYDROLOGICAL PROCESSES: Wiley Online Library en_US
dc.subject catchment geomorphology en_US
dc.subject catchment response time en_US
dc.subject empirical methods en_US
dc.subject stepwise multiple regression analysis en_US
dc.subject time parameters en_US
dc.title Derivation and verification of empirical catchment response time equations for medium to large catchments in South Africa en_US
dc.type Article en_US

Files in this item

This item appears in the following Collection(s)

Show simple item record

Search DSpace


My Account