In order to play the full benefits of the project and protect the environment of water source area and based on the overall investigation and analysis of water sources where the projects was built,the impact of the newly built projects to water source protection area is analyzed,forecasted and evaluated.By the typical project and adopting the two-dimensional steady state water quality mixed mode,the impact is forecasted and analyzed in the mixing process.Meanwhile,according to the predictive analysis results,the countermeasures is proposed in order to provide the scientific basis for project decision and water source protection.