Editing Cagayan River (section)

==Flooding==
The Cagayan River and its tributaries are subject to extensive flooding during the [[monsoon]] season in [[Southeast Asia]] from May to November.

The average annual rainfall in {{convert|1000|mm}} in the northern part and {{convert|3000|mm}} in the southern mountains where the river's headwaters lie. Water from the mountains flow down very slowly because of surface retention over the extensive [[flood plain]], the [[gorge]]s in the gently-sloping mountains and the meandering course of the river.

[[Inundation]]s of the Cagayan River and its tributaries have caused great loss of life and property and substantial losses to the local and national economies. The Philippine government has established several flood warning stations along the river. Experts are specifically monitoring the lower reaches from [[Tuguegarao]] to Aparri and the [[alluvial plain]] from [[Ilagan]] to [[Tumauini, Isabela]].

In November 2020, after the onslaught of [[Typhoon Vamco (2020)|Typhoon Vamco]] (Ulysses), the river reached its peak level and caused floods along its vicinity due to the rainfall accumulated from the typhoon. This flooding was one of the worst floods in the river's history. The [[Magat Dam]] also contributed to the floods along the river when its floodgates opened due to a potential overflow.<ref>{{cite news |last1=San Juan |first1=Alexandria Dennise |title=Residents near Ipo, Ambuklao, Binga, and Magat dams warned of flooding as reservoirs continue to release water |url=https://mb.com.ph/2020/11/13/residents-near-ipo-ambuklao-binga-and-magat-dams-warned-of-flooding-as-reservoirs-continue-to-release-water/ |access-date=December 22, 2020 |work=[[Manila Bulletin]] |date=November 13, 2020 |quote=Magat Dam in Isabela province has also released water at 5,073 cms as seven gates have been opened 24 meters.}}</ref><ref>{{cite news |last1=De Vera-Ruiz |first1=Ellalyn |title=Widespread flooding in Isabela, Cagayan feared as Magat Dam releases more water |url=https://mb.com.ph/2020/11/12/widespread-flooding-in-isabela-cagayan-feared-as-magat-dam-releases-more-water/ |access-date=December 22, 2020 |work=[[Manila Bulletin]] |date=November 12, 2020}}</ref>