The Pasig River (called Ilog Pasig in Filipino) is a river in the Philippines and connects Laguna de Bay (via the Napindan Channel) into Manila Bay. It stretches for 25 kilometres (15.5 mi) and divides Metro Manila into two. Its major tributaries are the Marikina River and San Juan River. The Pasig River is technically a tidal estuary in that the flow direction depends upon the water level difference between Manila Bay and Laguna de Bay. During the dry season, the water level in Laguna de Bay is low and the flow direction of the Pasig River depends on the tides. During the wet season, when the water level of Laguna de Bay is high, flow is normally from Laguna de Bay towards Manila Bay.

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