This is the first full scope study of wastewater reclamation and reuse on public WWTP in Taiwan, A 50 m(3)/day pilot plant with membrane and,biological systems of wastewater reclamation has been deployed and operated in the WWTP of Hsinchu Industrial Park, northern Taiwan. The reclaimed water has been transported to five factories and been used as the fresh water supply as well as the makeup water of cooling tower. The future construction of a 10,000 m(3)/day wastewater reclamation plant has been proposed and finiancially investigated. The business plan of BTO is proposed for future development, The 50 m(3)/day pilot plant consists of a membrane UF/RO system followed by the systems of high efficient biological oxidation systems BioNET and/or BAC. The bench-scale-membrane scaling/fouling test and magnetic anti-scaling system are also introduced to verify the mechanisms of membrane scaling and fouling. The result of the pilot study shows that the reclaimed water can conform the drinking water standard and can be used as the make-up water of cooling tower as well as the manufacturing water of many industrial. applications. The concentrate of RO process can fit the effluent standard and can be discharged directly to the river nearby., There are 88.6% of the factories in the industrial park express their willingness of using reclaimed water and 4600 m(3)/day is requested after the preliminary poll. The cost of reclaimed water is around US$0.54/m(3) (including construction, O & M and transportation) which is higher than the tariff of tap water (US$0.27/m(3)) but lower than the cost of seawater desalination as well as that of reservoir construction. Under BTO business plan, a wastewater reclamation plant of minimum 10,000 m(3)/day is proposed in order to make profit for future operation.