Once badly polluted, the Sepang Besar River is recovering. It’s greenish-blue brackish water today supports a thriving mangrove forest. Yet, 20 years ago, it was as good as dead. Universiti Putra Malaysia professor Dr Ahmad Ismail says both states must set aside river reserves and monitor pollutants, which include herbicides sprayed in oil palm plantations, effluent from shrimp ponds and surface run-offs.

http://www.star2.com/living/living-environment/2015/06/15/once-dead-sepang-besar-river-comes-back-to-life/