Estimating Culvert Capacity to Resist Flood Water

 Kulasi is one of the main rivers with catchment areas located in eastern part going down Mt. Isarog. The passage of the river crosses important roads and highways within the lower portion of the mountain, made of culverts and mostly were destroyed during the passage of typhoon Ulysses with international name VAMCO. This study describes a situation of the water course crossing after the extreme typhoon event. It derived hydrologic models that will be used to estimate the capacity of the culvert to handle excessive storm water event and it estimated the capacity of the culverts using the derived models. The evidences of culvert failure in different portions were presented. With known data of precipitation, watershed area, river surface slope and other parameters hydrologic modeling was shown to define the discharge capacity of the culvert pipe line at identified portion of the river. The capacity of the culvert pipe line was then computed using the derived hydrologic models. With the presented table, it expressed the capacity that flood water flow be accommodated in terms of actual precipitation and discharge at certain culvert pipe line. The procedure used on this study may be applied in other portions of the river and in other rivers.