The Davao Rivercatchment is the third largest river catchment on the southern Philippines island of Mindanao. It drains an area of over with a river length of. Most of the area is uplands. Average flows within the river near to the mouth are estimated at. The climate type is relatively uniform throughout the year with evenly distributed rainfall and temperatures and humidity. The area rarely experiences typhoons.
Stats
River Length:
Maximum Elevation:
Rainfall Average: Mean annual rainfall is 1800mm. Rainfall is evenly distributed throughout the year.
The landform and landcover within the basin is highly diverse. Ranging from lowland urban, agricultural, wetland and mangrove to natural riparian, plantations, upland agriculture and mountainous forest including primary forest. The area is classified by DENR as 77.5% forestlands and 22.5% alienable and disposable land. This is not a true land uses classification. Detailed land use is not available. Information is available from several sources including the Comprehensive Land Use Plan of the City, however this data is as yet theoretical and does not represent the realities or suitability of land at the barangay level. However the City Planning Office is collecting and digitizing data for land use maps.
River discharge measurements taken from 1984 to 1990 indicated an average river flow of approximately 78 cubic meters per second for the period. The main drinking water sources for Davao City are in the neighboring Talomo watershed. These sources are under pressure and the Davao River Basin is likely to be required for water abstraction in the near future. The Environmental Management Bureau samples 8 sites from the confluence of the Tamugan river downstream to the mouth of the river. From the Tamugan River confluence with the Davao River down stream to DDF Subdivision, Mandug the water is classified as Class A – Public Water SupplyClass II. Downstream of this point to the sea is classified as Class B or recreational water class I. Analyses for dissolved oxygen over the past 4 years has indicated no significant change in quality. The current monitoring of water quality is insufficient to monitor and evaluate pollution levels and trends in the river.
