The uncontrolled growth of water hyacinth posed a number of problems such as restricting the river flow and causing the water to become stagnant; making it difficult for fishermen and boatmen to maneuver their boats, especially the ones with motor engines, due to entanglement; clogging the drains and other waterways which, in turn, could cause floods; and turning the Oya River into a hideout for crocodiles. The Ministry of TransportSarawak will cooperate with the Department of Irrigation and Drainage and Universiti Malaysia Sarawak in conducting a comprehensive study with regards to the problem.
Crocodile attacks
Reports of saltwater crocodile attacks are pretty common especially at the downstream part of the river. The victims of these attacks are mostly fishermen who depend on the river for their livelihoods. A joint operation by Sarawak Forestry Corporation and Royal Malaysia Police in March 2021recorded 22 sightings of the reptiles. A 4.5-meter crocodile was caught during the operation.