| Attributes | Description | Number of classes | Level |
| Quantity of treated wastewater | The capacity of the wastewater treatment plant can be increased to treat the wastewater generated with primary treatment. The respondents were asked to consider the level of the total wastewater they want to treat | 4 | 40% 60% 70% 90% |
| Restoration the ecosystem in Nhue-Day River Basin | There are no investments to restore or improve the recreational activities provided by the Nhue-Day River Basin, such as fishing or swimming at present | 2 | No Yes |
| Improvement of wastewater collection system | Improvement of wastewater collection system could bring to higher flow rate of wastewater discharged to the wastewater treatment plant and prevent the odor or smell from long time wastewater accumulation so as to minimize the health and environmental risks | 2 | No Yes |
| Monthly additional environmental fee | A pilot Contingent Valuation survey will be used to determine 4 levels of the payment vehicles in thousands Vietnam Dong. These are the additional amount of money levels which households are WTP monthly | 4 | 50 100 130 200 |