When one looks at the stat of our country's waterways, it's hard not to get a little discouraged. While the Pasig River has always been held up as an example, it isn't the only body of water in the country that needs a clean up. For instance, the Marilao-Meycauayan-Obando River System (MMORS) was named as one of the filthiest places in the world by a New York-based environmental watchdog group back in 2007, ranking it alongside Chernobyl, site of the infamous nuclear reactor accident. Much of the pollution in the MMORS is attributed to tanneries that dump untreated hexavalent chromium into the river system, but the cost of removing the hexavalent chromium is equally as damaging.

Lim, R. S. (2013, February 26). Fighting Fungi: A Thomasian's project could pave the way for environmentally-friendly way to clean polluted rivers... Manila Bulletin, pp. F-1, F-2.