Eutrophication of Manila Region, Philippines

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In the Philippines about 37% of the total water pollution originates from agricultural practices, which include use of animal waste, fertilizer and pesticide runoff. As a consequence, eutrophication is observed in the Manila coastal region in connection with the major drainage region around Manila. The PasigMarikina-Laguna de Bay Basin as a water drain to Manila Bay is unique because it represents an interconnection between several water bodies and is partly controlled by the Manggahan Floodway and the Napindan Hydraulic Control Structure. The high nutrient emission from Manila and the catchment area around the Manila Bay results in eutrophication of the bay and its adjacent coastal waters. Chlorophyll estimates with satellite measurements show elevated levels and it seems that eutrophication of Manila Bay is present throughout the year but is decoupled from the monsoon seasons.