Waste stabilization ponds are an excellent alternative for municipal wastewater treatment in many developing countries located in tropical areas. This research study shows behavior results of several physicochemical parameters from the treatment system of Puerto Berrío Municipality in Colombia, a city with a hot and humid weather. Two field monitorings were carried out, one in the dry season and another in the rainy one at the inlet and outlet of the treatment system. Results showed a good behavior in the removal of main pollutants from the treated wastewater.