PTT Lampang, “Happiness Center”, is an eco-community park located next to PTT Petrolium Depot. The project intention was to encourage a living harmony between the factory and local community. This park acts as a place for a collection of native & rare plant varieties while also providing planting plots for local school and re-forestation plots. In term of water management practice, the park itself serves as a large water retention area, which helps absorb excess runoff overflow during heavy rainfall events. The grading design was coordinated with the client to provide a volume capacity sufficient enough to relieve the impact of annual flood events. The constructed wetland was incorporated to improve the water qualities from the water runoff of the adjacent waterway connected to community and urban area.