The rising cost of land across the globe has led to economic problems. One of the challenges brought by the high land price is constructing wastewater treatment systems with a small footprint. This paper compares the design of two domestic wastewater treatment systems, the activated sludge process (ASP) and trickling filter (TF), to determine which design requires the least area of land. The conventional activated sludge process design used the ASP equation, and the TF design used Rankin's method. The results showed that both systems have good removal efficiency. The ASP has a surface area of 3864 m2, and the surface area for the TF is 5000 m2. Therefore, the ASP is the better alternative when constructing a wastewater treatment system on a small land area.................. Keywords: ...............Activated Sludge, Trickling Filter, Wastewater Treatment Plants, Biological Oxygen Demand.