The Kulador Treatment Plant of Catbalogan Water District is located 2.7 kilometers from Barangay San Andres of Catbalogan, Samar, or 110 48' 44.4" N and 240 54' 10.3" E.

The plant receives water from the Antiao River through a spillway which is 16 meters wide and 1 meter tall. The trapped water goes into a sedimentation box that limits sediments. It has a size of 2.1 meters x 1.8 meters x 2.0 meters. After the sedimentation process, the water goes directly to the Rapid sand filter, which is 2.5 meters x 5 meters x 3.5 meters. Then it will go to the slow sand filter through an 8-diameter perforated GI pipe. The slow sand filter is around 19.5 meters x 8.5 meters x 2.2 meters.

The plant is also equipped with a backwash tank with a size of 6.6 meters in diameter and 3.55 meters in height. The final stage of the treatment is the chlorination process through a chlorination tank. The filtered water goes to two transmission lines 6 diameters CI and 8 diameters GI. The current discharge of the Kulador treatment plant is 20 liters per second.

The treatment plant was passed by Catbalogan Municipal Waterworks year 1979 when the Catbalogan Water District was created.