In the model,the three indexes: pollution sources,water quality,zoology are used to establish a comprehensive assessment index system for water environment security assessment of trans-basin water transfer project.

On the healthy water cycle and sustainable water utilization;

Based on the analysis of healthy water cycle concept of wetland and its connotation,and the pressure-state-response(PSR) conceptual model for wetland healthy water cycle is proposed.

An approach of integrated water resources planning is put forward based on the prediction of water supply and demand,the protection of water resources and the water saving under the idea of healthy water cycle.

The fecal coliform group was taken as the health safety assessments index,and Monte-Carlo technology was used to carry on the simulation of model establishment and the certainty of probability distribution,then simulation of health safety certainty of evaluating objects which were reused for urban reclaimed water consumption was carried out by using Crystal Ball soft.