Abstract: Sensitivity analysis is a crucial procedure for parameter identification. The parameter sensitivity of hydrological and contaminated modules in Storm Water Management Model (SWMM) was evaluated with three different intensities of rainfall based on the Morris screening method. The results showed that the descending order of parameter sensitivity to total runoff volume and peak flow was destoreimperv, conduit roughness and width-K, with sensitivity indices of -0.329, -0.144, 0.133 and -0.294, 0.171, 0.143, respectively. Max buildup, coefficient and exponent of road and roof parameters had higher sensitivities to water quality modeling. Rainfall intensity had a great influence on the sensitivities of infiltration parameters, but a weak influence on the sensitivities of water quality parameters. Land use had a great influence on the
parameter sensitivity. The parameters of water quality were more stable than those of hydrological module in SWMM.

Key words: improved TOPSIS method, Zhangjiajie, early warning, grey GM (1,1) model, tourism ecological security