URBAN ....
as they function to store surface water during monsoons and ensure water availability during dry seasons. Wetlands also control floods by absorbing excess water and protecting nearby settlements from flooding.
Manalo authored a study about Davao City wetlands entitled Land Use Change of Wetlands in Davao City.
“Atong mga klaseklaseng riverways ug waterways, wala nato naapil sa atong plan kaniadto bantog daghan communities ang at risk (Our various riverways and waterways were not included in the plans in the past, which is why many communities are at risk),” Manalo said.
In his study, which uses historical land use changes using old Spanish and American-era maps of the city, it was determined that Davao City was settled in an area with a large network of riverine and estuarine wetlands connected by creeks and waterways.
Agdao tidal marsh
One large wetland is in Agdao, in the area around
Jerome Street in R. Castillo Avenue, which in the 1940s was a tidal marsh. Today, it is a heavily populated area in the city, and the remnants of the tidal marsh are drainage canals that run along the community.
“Tidal marshes diri musulod ang tubig dagat, kung high-tide siya diri muadto sa mga areas, but since wala na sila karon kaning tidal marsh nahimo na siyang settlements and tubig muadto na sa drainage, ang tidal seawater didto na musulod sa mga drainage canals, which is insufficient na pundohan ug tubig (Tidal marshes are where the sea water enters during high tide, but since there is no more tidal marsh, the tidal water now settles and goes into the drainage canals, which could not store water),” Manalo said.
Laverna
Another flood-prone area in Davao City is Laverna, near the Davao International Airport.
Laverna is a wetland formed because of blocked floodwaters and the alteration of drainage and creekways at Davao International Airport.
He said that in recent years’ settlements, commercial establishments, and infrastructure were built in the wetland.
“Nawala na ang wetland (the wetland disappeared)," Manalo said of the Laverna wetland.
Matina wetlands
“We have several wetlands in Matina, and they came from the previous floodplains of the Davao River,” Manalo said.
The Matina portion of the Matina River is a lowlying area before it reaches the Shrine Hills.
“Taas ang elevation sa Shrine Hills area and its slope is rigid. Normally, areas under this type of geological formations diri pud magtapok ang wetlands,” Manalo said.
He added that the old course of the Davao River curved its way to the Matina area, noting that “maybe in the 18th or 19th century the river once passed through that area.”
He said there are wetlands that serve as a catchment area of Shrine Hills, particularly the wetland in Juna Subdivision inside Jaroda compound; one wetland near the Alexian Brothers; a wetland inside Davao Global Township; and a wetland inside Coca Village.
“These wetlands are perfect examples coming from a riverine influence. They are effectively functioning wetlands; we really need these wetlands,” Manalo said of the need to preserve them.
Bajada, Barrio Obrero wetland
Another flood-prone area is J.P. Avenue facing Victoria Plaza Mall. Manalo said the area is a wetland but due to development, it has been converted into linear structures, which are the drainage canals of today.
“Tung creek na tapad sa Victoria Plaza dako to siya na wetland sa una. So, kaning mga wetlands sa una tong nakita sa 1944, naturally siya naga flow, so naa na siya kaugalingon na creeks naka konekta so mao na siya gitambakan gihimo linear (The creek beside Victoria Plaza was a big wetland in the past. The wetlands we saw in 1944 had their own flow, so they had interconnecting creeks, which were filled up),” Manalo said.
Policy advocacy
Manalo called on the government and owners of private property, like real estate projects where wetlands are located, to preserve these spaces which are crucial to mitigate flooding in the city.
“Ang pwede buhaton sa subdivisions is to leave those wetlands; do not reclaim them, ayaw tambaki (do not fill it up) to make them functional wetlands,” Manalo said.
He added that as part of their policy advocacy, they already submitted two wetland studies (historical study and ecological profiling) to the public and different government agencies, particularly the City Government of Davao’s City Planning and Development Office.
“They (CPDO) already included our recommendations in the crafting of the newly approved Comprehensive Land Use Plan (CLUP) of Davao City,” Manalo said.
Councilor Temujin Ocampo, who sits as chairperson of the committee on environment and natural resources, said the newly approved CLUP will hopefully preserve the remaining wetlands of Davao City.
He said the loss of the wetlands decades ago was due to spot zoning, where settlements and establishments just built on environmentally critical zones like wetlands.
“With CLUP, nakaidentify na ang mga area, mga zones asa nato ibutang mga subdivision, asa nato ibutang mga commercial establishments (The CLUP identified the areas and zones where we can put the subdivisions and commercial establishments, and this will protect the wetlands),” Ocampo said.