Renewal and Update of MTO IDF Curves: Defining the Uncertainty
Renewal and Update of MTO IDF Curves: Defining the Uncertainty
Previously Published Material: Accepted, but not yet published, for journal publication by the Journal of Water Managment Modeling. Parts presented at the Ontario Climate Advisory Committee (OCAC) meeting #45. Preliminary finding were presented at CMOS 2012 and 2013.
Abstract ID#: 35608
English Abstract:
The University of Waterloo has been commissioned by the Design and Contract Standards Office of the Ministry of Transportation of Ontario (MTO) to update the intensity–duration–frequency (IDF) curves that are used to estimate design storms for drainage infrastructure. Environment Canada provides analyzed rainfall data for weather stations in Ontario. Project engineers determine the design storm parameters using a variety of methods. Thus, there is a need for a consistent interpolation procedure that can deal with the sparseness and unevenness of the Ontario station network. This presentation describes the procedures that form the basis for the MTO IDF Curve Lookup system. Confidence limits assist in the design process and allow comparison with other results. These were used to assess the spatial bias in the error fields. There appears to be none, but there is room for improvement where there are sharp changes in geography, such as the highlands west of Thunder Bay. Validation curves are presented for several Canadian stations and one American station.