Lake Toba, North Sumatera is one of the national tourism areas in Indonesia that has water pollution problem due to the unsustainable development especially in the catchment area. To support Lake Toba Tourism Area and to educate the people about sustainable development, Ministry of Public Works and Housing, Republic of Indonesia built integrated tourist toilets equipped with wastewater treatment plant at Menara Pandang Tele Area, one of the most strategic tourism attraction located in the catchment area of Lake Toba. The wastewater treatment plan is not only to use biofilter but also Kolam Sanita (wetland) as secondary treatment. This study would like to see how the wastewater treatment plant at Menara Pandang Tele is designed and see what modification are made from the original design to make it well functioned. This study uses a quantitative method to calculate the volume of the wastewater treatment plant. Further calculation is also needed to determine the dimension of the technologies. The geographical character is the main aspect to be considered in this step. The results showed that to meet the quality standard of the wastewater, the biofilter technology is determined to use three processing stages starting with equalization, primary sedimentation, and secondary process which consist of anaerobic process and clarifier. The dimension modification must not be more than two meters in height. Kolam Sanita is needed to make sure the effluent quality will not harm the groundwater. The modification is required due to the various heights of the ground level and makes the design representative of aesthetic function.