... harvesting, urban ecology and landscaping improvement, increase of commercial value of the land and improvement of living standards. In order to implement sustainable wastewater management in the urban ... 37,000 m3. Therefore, if the water surface in the city is 7% of the total surface area of the basin, the total water volume to be directly drained off remains half. Besides, there are other added ... unpredictable urban hydrology patterns, etc. what impact on collection and conveyance of urban wastewaters. 2. APPROACHES AND MODELS FOR SEWERAGE AND DRAINAGE IN VIETNAMESE URBAN AREAS Sustainable...