Why does it flood easily in Pampanga? Why do floods come fast and leave slowly? The quick answer: There are more rivers converging here than anywhere in the country, and the water they carry is more than the channels can contain because (a) those channels are heavily silted, (b) fishponds slow down the flow, and (c) the province is literally sinking into the sea due to a phenomenon called subsidence. So our flooding problem is a natural occurrence compounded by human intervention.
Many towns in Pampanga, Bulacan, Nueva Ecija and Tarlac actually sit on ancient lakes and swamps (“pinac” in old Kapampangan), which are (a) the Pinac de Candaba where Candaba, San Luis, San Simon, Apalit, Baliuag, San Miguel de Mayumu, San Ildefonso, Pulilan, San Rafael and Cabiao are located; (b) the Pinac de Hagonoy where Calumpit, Hagonoy, Plaridel, Malolos and Paombong are found, and where the Angat River joins the Pampanga River via the Bagbag River; (c) the Pinac de San Antonio, located north of Mount Arayat in Nueva Ecija; and (d) the Canarem Lake, located in Victoria, Tarlac, which has become shallow and is now just a wetland and bird sanctuary formerly known as Catanglaran, which means “where tanglad plants grew abundantly.”
These swamps--the Hagonoy Swamp, the Candaba Swamp, the San Antonio Swamp, and the Canarem Wetland--are located in a low-lying corridor that runs from Nueva Vizcaya all the way down to Manila Bay. It's called the Pampanga River Basin. It's where two big rivers, the Rio Grande and the Rio Chico, meet and merge, and where all rivers,streams and rivulets coming from all directions in Central Luzon--Sierra Madre, Caraballo and Zambales mountain ranges--collect and pass right through Pampanga before exiting to the sea. Imagine Central Luzon as a sink, and Pampanga as the sinkhole.
The direction of floods is mostly towards Bulacan because the Arnedo Dike (built during the term of Pampanga Gov. Arnedo in the early 1900s) on the Pampanga side of the Pampanga River, keeps the overflow water from spreading towards San Fernando and the rest of our province. Without this dike, the floods from Pampanga River would be evenly spread on both sides. (To be continued)