With　the　increasingly　degraded　water　environment,　some　substances　will　gradually　accumulate　in　our　drinking　water　source-the　surface　water,　and　finally　threaten　drinking　water　safety　when　their　contents　reach　a　certain　amount.　To　give　early　warning　on　those　potential　threats　to　water　safety,　we　can　choose　corresponding　water　quality　control　indexes,　i.e.　water　quality　factors,　to　take　proper　countermeasures　by　building　a　water　quality　model　simulating　change　trend　of　the　water　source　quality　based　on　historical　data,　which　is　favorable　for　ensuring　the　water　source　quality.　(C)　2011　Published　by　Elsevier　Ltd.　Selection　and/or　peer-review　under　responsibility　of　the　Intelligent　Information　Technology　Application　Research　Association.