A new method for estimating trash screen blockage extent

This paper presents findings from research that examined the potential for developing equations that predict the extent to which trash screens at culverts are likely to become blocked. This was assessed using multiple regression analysis in which the average area of debris blockage at screen faces calculated from field inspection records obtained from 140 screen sites in Belfast, Northern Ireland, was correlated with pertinent driving variables including channel properties, flow characteristics, landuse types, the degree of social deprivation and the properties of the screens themselves. This analysis enabled the development of simple empirical equations requiring input data that can be extracted from readily available sources. The key variables identified and the properties of the equation coefficients are discussed within the context of their statistical significance.