Written by: Rendel Ang
Artwork by: Michael Dunuan
Sustaining the ecology and socio-economy of the Pasig river is what determines the outcome of its ecosystem. A planning framework that satisfies land and freshwater ecosystems is therefore necessary. In an interview with the Environmental Management Division of the Pasig River Rehabilitation Commission (PRRC), they stated that a framework of rehabilitation programs, projects and activities have been implemented under the 2017 to 2032 Pasig River Integrated and Strategic Master Plan (PRISM) in collaboration with UP Planades. It is a structure of implemented programs in rehabilitation, projects and activities by the commission. The formulation of the master plan acquired inputs from the chemical engineers of the Department of Environment and Natural Resources (DENR) and Laguna Lake Development Authority (LLDA).
In accomplishing the master plan, repeated testing of the water’s quality serves as a prerequisite in formulating techniques in environmental adaptation and mitigation. The improvement in the condition of waterways were observed through the positive change in fecal coliform, nitrate, phosphate, oil and grease, total suspended solids (TSS) and heavy metals. There is also the increase in the river’s biodiversity where in tilapia, a common freshwater fish, is recently reported to be caught (Madarang, 2019), but biodiversity doesn’t necessarily equate to the river’s improvement. There are recent warnings against the consumption of fish caught in the river, a result of determining the fecal coliforms and heavy metals in its tissue in the 2019 Fish Tissue Analysis Report of Pasig River. These data were interpreted from water quality tests by chemical engineers. They determine the factors influencing the current state and the factors that benefit the Pasig River through the same process.
Laguna lake, which is connected to the Pasig River, is one of the sources of its biodiversity through the fish carried by the flushing water from the lake to the river, due to the rainy months of June to December. The aquaculture potential also increases because of the increase in dissolved oxygen content as a result of the flushing effect (Cruz, 1997). The LLDA allows liquid waste to be received by the lake, but it is regulated to ensure that only limited volume is discharged at a certain time. It is done through the LLDA Resolution no. 286, which issues discharge permits and fine those who go against the Republic Act 4850, which created and gave power to LLDA (Laguna Lake Development Authority, 2006). Determining and regulating effluent liquid wastes discharged is also heavily dependent on chemical engineers because the amount of liquid waste is determined through the same heavy metal and coliform constituents. An engineer’s report is a prerequisite in acquiring discharge permits where in the chemical composition, total daily volume, and the nature and character of wastes along with the process of treatment and estimated efficiency of the treatment are requirements within the technical report. The effluent’s total daily volume of water composition after treatment is also required (Laguna Lake Development Authority). This prevents the lake from imitating the state that the Pasig River resulted in after the indiscriminate dumping of wastes by both informal settlers and industries.
The Presidential Decree No. 600, also known as the Marine Pollution Decree of 1974 states that the quality of the marine environment and the biodiversity it supports must not be impaired as it is of vital importance to humanity and assuring that it is managed and protected is the interest of all people (Philippine Coast Guard). Chemical engineers serve a vital role in the implementation of the decree because water quality level is an indicator of the biodiversity that the body of water could foster. Proposed water quality improvement innovations are assessed by chemical engineers along with the implementation of existing technologies. But it is not restricted to the application of ideas as the wide variety of skill chemical engineers possess are geared towards improving the quality of people’s lives.
References:
Cruz, R.T. (1997). Case Study III – The Pasig River, Philippines. 11 New Fetter Lane, London: E. & F.N. Spon.
Laguna Lake Development Authority (n.d.). Discharge Permit (DP) New. Retrieved from http://llda.gov.ph/discharge-permit-dp-new/
Laguna Lake Development Authority (2006). Resolution No. 286, Series of 2006: Adopting the Reckoning Period for Imposition of Administrative Fine for Operating Without Valid LLDA Clearance and Discharge Permit. Retrieved from http://llda.gov.ph/wp-content/uploads/dox/br/dp/br286s2006.pdf
Madarang, C.R. (2019). Freshwater fish tilapia caught in Pasig River years after rehabilitation. Interaksyon. Retrieved from http://www.interaksyon.com/trends-spotlights/2019/01/29/143140/freshwater-fish-tilapia-caught-in-pasig-river-after-years-of-rehabilitation/
Philippine Coast Guard (n.d.). Presidential Decree No. 600: Prevention and Control of Marine Pollution. Retrieved from http://www.coastguard.gov.ph/index.php/related-laws/29-auxiliary-menu/related-laws/189-presidential-decree-no-600
