Author(s): Nicholas Wallerstein; Scott Arthur
Linked Author(s):
Keywords: No Keywords
Abstract: This paper presents scientific findings generated from a research theme within the Flood Risk Management Research Consortium project (Phase 2) which has been tasked with developing and improving models that can be used to predict blockage at structures such as bridges and culverts caused by trash accumulation, especially those which have trash or security screens in place. The project aims to build upon current trash prediction methods by examining this complex issue through the use of field datasets, a targeted online questionnaire and through face-to-face interviews and site visits. The research described herein presents the initial analysis of a field dataset that has enabled empirical formula to be derived that will help to determine the likelihood of blockage at culverts. The dataset consists of blockage records logged at one hundred and forty screens in Belfast, Northern Ireland, by staff of the Northern Ireland Rivers Agency. From this dataset the probability of blockage at screens caused by trash was determined and then correlated with what were considered to be the pertinent driving variables including: channel network length upstream of the screen; upstream channel slope; upstream landuse characteristics, and; local social indices. Correlation between these parameters has enabled the generation of empirical formula which may be used to estimate the probability of blockage at any given screen based upon these variables. The probability of blockage at a screen was calculated and correlated on an annual, seasonal and monthly basis thereby enabling the asset managers to consider risk over different temporal scales. It is intended that the models being developed in this project, once validated, will be incorporated into flood risk assessment tools such as the Modelling and Decision Support Framework project (MDSF) and the Flood Risk Assessment under Climate Chance Scenarios Project (FRACAS).
Year: 2010