3.2.1 Single variable regression analysis
The relationships between the 350-year water level (estimated using a GEV distributions fitted to gauged level data at 23 stations and a set of individual predictor variables were initially tested using single variable regressions. Note that these 23 stations are a subset of the 31 stations with at least 25 years of water level data, as for this analysis we also needed LiDAR data as well as HYDROTEL discharge data to be available. The first step consisted of identifying significant correlations between water level and any single variable such as lake area, upstream drainage area, peak discharge or outflow channel width. The results showed no statistically significant relationship existed between water levels and any single variable; performing standard transformations to the variables, such as applying a logarithm or square root, did not yield any improvements.