The Brigalow Catchment Study: Effects of land development on peak runoff rate and its prediction in central Queensland, Australia

No Thumbnail Available
File version
Author(s)
Thornton, C
Yu, B
Griffith University Author(s)
Primary Supervisor
Other Supervisors
Editor(s)

Grantley Smith

Date
2012
Size
File type(s)
Location

Sydney, Australia

License
Abstract

Commencing in 1965 and continuing today, the Brigalow Catchment Study in central Queensland has measured both runoff volume and peak runoff rate from three catchments (11.7 to 16.8 ha) which were initially covered with native brigalow scrub. Thirty-eight years of data were used to assess the accuracy of three different methods for estimating peak runoff rate, and then, to quantify the changes in peak runoff rate as a result of clearing two of the three catchments for either cropping or pasture. Three methods were used to estimate the peak runoff rate for the 3 catchments: 1) multi-variable regression; 2) Soil Conservation Service Curve Number (SCS-CN) method; and 3) Spatially Variable Infiltration model (SVIM). Regression analysis showed that peak runoff rate was strongly correlated with total runoff volume, in addition to 3 rainfall related variables. Regression method yielded the best results of the three methods tested. Estimates using the SCS-CN method were strongly correlated with observed peak runoff rate for all catchments. However, the method typically underestimated for small events and overestimated for large events. Estimates using SVIM with linear kinematic wave routing were strongly correlated with observed peak runoff rate for all catchments. Prior to land use change, peak runoff rate from the three brigalow scrub catchments averaged 3.4 mm/hr. A significant increase in peak runoff rate from both the cropping and pasture catchments was clearly evident and attributed to land use change, with the average peak runoff rate increased by 9.1 mm/hr for the cropping catchment and 3.4 mm/hr for the pasture catchment. This equates to an increase of 263% and 164%, respectively, to estimates of their peak runoff rate had they not been cleared. Increases in the peak runoff rate were largest for smaller storm events with an average recurrence interval of less than two years under cropping and less than four years under pasture.

Journal Title
Conference Title

Proceedings of the 34th Hydrology and Water Resources Symposium, HWRS 2012

Book Title
Edition
Volume
Issue
Thesis Type
Degree Program
School
DOI
Patent number
Funder(s)
Grant identifier(s)
Rights Statement
Rights Statement

Self-archiving of the author-manuscript version is not yet supported by this conference Please refer to the conference link for access to the definitive, published version or contact the authors for more information

Item Access Status
Note
Access the data
Related item(s)
Subject

Surface water hydrology

Persistent link to this record
Citation