Parts of the Imus River in Cavite are still in relatively good condition, with ample vegetation and aquatic life. Shown is a lush upland riverscape in Silang, where fish and small crabs still abound. (PRF)


The Imus River Watershed is one of six river systems located in the Philippine province of Cavite, south of Manila.

It flows into Manila Bay, a known pollution hotspot. Rivers like it often act as major pathways to transport waste, particularly non-biodegradable plastics. Most of the land-based waste which enters rivers inevitably end up in the ocean.

The watershed is comprised of 36 main river segments and 56 perennial or permanent streams with a total length of 186.15 kilometers. Its total drainage area spans 11,259.80 hectares. A a total of 222 barangay communities are fully or partially situated within the boundaries of the watershed, which as of 2015 hosted at least 1,351,057 people.

Its elevation ranges from zero to 655 meters above sea level, dividing it into three sub-watersheds, each with its own unique characteristics.



The river system begins in the cooler upland area covering parts of Silang, Amadeo and Tagaytay. A central hilly area covers parts of Imus, Bacoor and the majority of communities in Dasmariñas and Silang. Near the humid coastline are lowland portions covering parts of Kawit, Imus and Bacoor.

Normal mean temperatures ranged from 26.20°C to 28.53°C, while average total annual rainfall ranged from 2,265.69 mm to 2,483.05 mm. The average water flow during wet season was 1,601.84 liters per second, while the average water flow during dry season was 1,337.42 liters per second.

90.67% of Cavite, the province hosting the Imus River,  is classified as alienable and disposable land, divided into production land (55.24%) and built-up areas (44.76%). For more detailed and technical information, please check out MAPS and PUBLICATIONS.