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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