Coherent Identifier About this item: 20.500.12592/gffrbg

A sensitivity analysis of the Canadian Water Quality Index




As a follow-up to the recommendations from this workshop, the CCME commissioned this report, examining the sensitivity of the current index formulation, evaluating potential modifications to the index, and assessing the use of modified descriptive output categories for the CWQI. [...] The first component of the index is referred to as scope, and it measures the number of parameters out of compliance with objectives as a percentage of the total number of parameters measured. [...] The exclusion of fecal coliform results had most influence on the distribution of CWQI values, reducing the number of index values in the ‘poor’ and ‘marginal’ categories, and significantly increasing the number of stations in the ‘excellent’ category. [...] Basically, the synthetic data set consisted of varying the percentage of the number of parameters with exceedances and the percentage of samples with exceedances. [...] The purpose of this study was to quantitatively assess the sensitivity of the CWQI to the manipulation of the data that are fed into the index.


environment water quality drinking water water natural resources evaluation chemicals regression analysis statistics sensitivity analysis correlation and dependence parameter median variance p-value t-value categorical total suspended solids