Communities along the Tullahan River are now benefiting from the government’s and private sector’s flood mitigation projects. Flooding has been a regular occurrence in recent years in locations like Caloocan, Malabon, Navotas, and Valenzuela (Camanava). These four cities have developed a propensity for flooding, especially at high tides, during intense rainfall, and when rivers and dams overflow. They are situated in the estuaries of several river deltas. The Tullahan River is one of the linking rivers that regularly has an impact on these locations.
Pasig River (PNA file photo by Joey Razon)
Floods occurred in low-lying areas as a result of the river being clogged and constricted due to the pollution build-up. People who live in or close to riverbank communities have suffered as floods have grown more severe in recent years, often reaching depths of several feet. The river’s capacity to store water has allegedly decreased over time, as has its purported narrowing and shallowing, which cause the riverbanks to flood when it rains severely and reach low-lying and highly populated areas.
The Department of Environment and Natural Resources (DENR) and San Miguel Corporation (SMC) started the dredging and clean-up project for the 27-kilometer-long Tullahan River system in March 2019. It runs from Manila Bay in Navotas City to a section near the North Luzon Expressway in Caloocan City.
More than 1.12 million tons of solid waste that had been clogging the Tullahan River for a very long time were removed during the major clean-up project, which took two and a half years to complete. By removing waste, the river was widened and deepened in areas where silt had built up over time. This increased the river’s capacity and decreased flooding in flood-prone areas by opening up parts of the river that had effectively become bottlenecks.
The government constructed fortified river barriers and pumping stations to safeguard villages near the river, and these efforts were successful in preventing Camanava from experiencing major floods.
Within a year of the project’s start, communities reported a decrease in severe flooding in their areas because the Tullahan River was able to redirect more floodwater away from streets and towards Manila Bay.
With the success at the Tullahan River, optimism is even higher regarding what it can do at the Pasig River, which has already been cleaned up to a 1 million metric ton threshold in silt and solid waste by February 2023 since July 2021.
Critical sections of the Pasig River now measure five to six meters deep, up from just one to three meters at the beginning of the project, improving the passage of more floods out to Manila Bay during the rainy season.
According to a 2021 study by ourworldindata.org, Pasig and Tullahan are among the top 10 plastic-emitting rivers in the world and are in part responsible for the plastic waste in the ocean. They are also the waterways where untreated sewage from Metro Manila generally ends up. Rivers from the Marilao-Meycauayan-Obando River System (MMORS), which SMC is anticipated to clean up next as part of its continuous campaigning, are also included on that list.
This is a commendable effort. All parties involved must demonstrate commitment, action, and behavioural change if we are to restore these rivers to a condition that allows them to sustain healthy marine life and make them a source of clean water.
Sources:
- Reyes, M. A. LL. (2022, September 3).Providing a head start. Philstar.com. https://www.philstar.com/business/2022/09/04/2207155/providing-head-start
- PNA (2023, January 31).Cleanup boosts Pasig River’s flood-carrying capacity. Philippine News Agency. https://www.pna.gov.ph/articles/1194052
- SMC cleanup of San Juan River in progress, boosts larger Pasig River cleanup. San Miguel Corporation. (n.d.). https://www.sanmiguel.com.ph/news/smc-cleanup-of-san-juan-river-in-progress-boosts-larger-pasig-river-cleanup#:~:text=The%20project%20was%20completed%20in,Malabon%2C%20Valenzuela%2C%20and%20Caloocan.
- Share of ocean plastics that come from the largest emitting rivers. Our World in Data. (n.d.-a). https://ourworldindata.org/grapher/plastics-top-rivers
- Staff, C. P. (n.d.).1-billion dredging project on Tullahan River can solve Bulacan’s flooding problem. cnn. https://www.cnnphilippines.com/news/2020/2/24/Tullahan-River-project-Bulacan-flooding.html?fbclid=IwAR3_I5CHW-gtl-NiF1B3PkFGPSjveYHtXy7wBNgwgnQctrhF6ncLTdlG5lk
