Layawan River: Resources, Issues and Water Quality | JBES 2025

Princess Krishyll B. Andong,  Christine Marie V. Casal,  Wella T. Tatil, and Armi G. Torres, from the different institute of the Philippines. Wrote a research article about Layawan River: Resources, Issues and Water Quality. Entitle, Layawan River, Polanco, Zamboanga Del Norte, Philippines: Resource utilization, environmental issues and water quality. This research paper published by the Journal of Biodiversity and Environmental Sciences | JBES. an open access scholarly research journal on Environmental Sciences. under the affiliation of the International Network For Natural Sciences| INNSpub. an open access multidisciplinary research journal publisher.

Abstract

The Layawan River is a vital freshwater ecosystem in Polanco, Zamboanga del Norte, Philippines. The Integrated Watershed Management Plan of Layawan River targets to establish conservation and protection efforts. However, information crucial for its management and conservation remains scarce. This study assessed the resource utilization, environmental issues and water quality along the lower reaches of Lawayan River in Polanco. The river supports subsistence fisheries and sand-gravel quarry industry and provides water for agricultural (irrigation) and domestic (cleaning, washing clothes, and bathing) use. Along with its contribution to the community lies the associated threats it faces. It is mainly threatened by unregulated disposal of garbage, sand and gravel quarry, and open defecation. While majority of the water quality parameters passed the national standard, concerns arise with its high phosphates, total suspended solids (TSS) and total coliform counts. Phosphates readings from 0.099 to 0.144 mg/L failed the 0.025 mg/L threshold, indicating excessive nutrients. TSS values reached up to 109 mg/L, exceeding the 50 mg/L limit. Total coliform counts ranging from 3,700 to 35,000 MPN/100 mL are appalling, indicating potentially extreme fecal contamination and posing health risk to the public. Efforts for sustainable management of Layawan River should focus on strict implementation and enforcement of environmental laws (e.g., R.A. 9275 Clean Water Act; R.A. 9003 Ecological Solid Waste Management), monitoring of water quality, IEC campaigns to raise the level of awareness and participation of the community, reforestation of riparian zones, and mitigation measures to address the potential health risk to the public.

Introduction

Rivers are significant in all aspects, whether historically, culturally, biologically, or geologically (Cuivillas et al., 2016), and are essential to human survival (Basak et al., 2021).

Living in a world with diminishing freshwater resources impacts human well-being and affects vital life-support systems at our end (Albert et al., 2021). Having healthy rivers is crucial (Grill et al., 2019), for it is considered the lifeblood of humans (Basak et al., 2021).

The first-ever worldwide evaluation of the planet's surviving free-flowing rivers found that one-third (37%) of the world's longest rivers remain freeflowing, highlighting severe ecological degradation (Grill et al., 2019). The State of Global Water Resources Report 2022 also revealed that the global catchment areas display an alteration from normal conditions and are observed as drier than usual (World Meteorological Organization, 2023).

Nearly 27% of freshwater species are in danger of extinction, and the rate of wetland loss, which includes rivers, is three times faster than that of forest decline (Stefanidis and Papastergiadou, 2024). In recent studies, 25% of the world’s freshwater fauna, including fish, are threatened with extinction (Sayer et al., 2025). However, despite their essential contribution to the well-being of humans and their necessity to global biodiversity (Darwall et al., 2018), freshwater ecosystems are deemed to have less research embarking and conservation efforts when compared to both terrestrial and marine environments (Escatron et al., 2022). Hydrological alterations, overexploitation, habitat degradation and loss, pollution, invasive species, and the multiple impacts of climate change are a few of the causes of these freshwater declines (Darwall et al., 2018; Sayer et al., 2025).

The growing human population and socioeconomic activities are the major contributors to the rising nutrient loads and pollutants, leading to severe deterioration of water quality across different countries worldwide (Albert et al., 2021). Changes brought about by humans also significantly impact the provision of ecosystem services, which affects human welfare. Hence, conservation management must be implemented to enhance biodiversity, ecological quality, and the availability of clean water and other ecosystem services for human use (Stefanidis and Papastergiadou, 2024). River evaluation and threat identification are essential to rehabilitate and protect them adequately (Magbanua et al., 2023).

Bohnet (2014) highlights that public perception and awareness of clean water are considered requisite parts of effective water resource management. To safeguard our freshwater ecosystem effectively, monitoring and managing it fairly to identify contaminants, address and control their effects, and assess the effectiveness of the existing environmental policies and protection programs for welfare and well-being is important.

In the Philippines, Layawan River is considered one of the sub-watersheds and serves as the primary source of sand and gravel in Zamboanga del Norte. In 2008, the Environmental Management Bureau (EMB) Region 9 classified Layawan River as a Class A water body. A Class A classification is a Public Water Supply Class II intended as sources of water supply requiring conventional treatment (coagulation, sedimentation, filtration, and disinfection) to meet the latest Philippine National Standard for Drinking Water (DENR Administrative Order No. 2016-08). Cuivillas et al. (2016) found that the river's water quality may be treated for potable use and is generally safe for recreational uses like swimming and bathing.

Human interventions over the years significantly contributed to the state of the Layawan River, making it a critical freshwater ecosystem. According to the Integrated Watershed Management Plan of Layawan River (IWMP), one of its goals is to establish a dependable environmental conservation and protection measure in response to the need for the earth's global biosphere rehabilitation. However, there are limited studies on the current environmental condition of Layawan River. This study aimed to address these gaps by assessing the current utilization, threats, and water quality of the Layawan River, Zamboanga del Norte. This also provides valuable insights for improving the existing management strategies and policies of the Layawan River and ensuring that Layawan River is managed sustainably to maintain its biodiversity, secure this multiple-use resource for future generations, and prevent health risks to the community. This assessment aligns with the Sustainable Development Goal (SDG) 6.6, which seeks to protect and restore water-related ecosystems, including mountains, forests, wetlands, rivers, aquifers, and lakes. Additionally, it supports SDG Target 15.1, which focuses on conserving and restoring the terrestrial and freshwater ecosystem for sustainable use.

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Article source : Layawan River, Polanco, Zamboanga Del Norte, Philippines: Resource utilization, environmental issuesand water quality