The “Zero-Discharge” Wastewater Treatment System has been advocated for the scenic and/or historically preserving tourism spots. The Decentralized Wastewater Treatment (DWT) coupled with the Land Treatment Method has been found to be the most effective treatment system to achieve such historically unachievable “Zero-Discharge” dream. The DWT, normally also referred as aerobic onsite or clustered wastewater treatment system, is installed to provide efficient treatment for group of residential dwellings and businesses in sparsely distributed community. It has been reported that the performance of commercially manufactured DWT is adequate in some cases but its reliability is questionable. In reality, the roots of its lack of reliability, is caused by the inappropriate handling and disposal of treated effluent. The objective of this paper is to present an innovative sustainable design approach for DWT based on extended aeration principles and complete effluent utilization by land treatment.