Last updated: May 2023
In 2005, a constructed wetland was established in Barangay Villareal, Bayawan City in order to improve a peri-urban settlement and promote domestic wastewater treatment with reed beds. The wetland covers an area of 2680 square metres and comprises two reed beds, with the first bed utilizing perforated pipes beneath a sand and gravel substrate for vertical flow filtering, and the second bed utilizing horizontal flow for biological filtering. The roots of the Phragmites karka reeds, which are used in the system, act as a natural filter, removing microorganisms and pollutants. The treated effluent is reused for various purposes, such as watering plants, firefighting, and irrigating ornamental plants and agricultural crops. The overarching objective of the initiative is to safeguard coastal waters from pollution caused by domestic wastewater and enhance residents' quality of life by providing safe sanitation and wastewater treatment facilities. Furthermore, the initiative seeks to showcase the effectiveness of constructed wetlands, encourage the use of locally available reeds for wastewater treatment, and conserve water and nutrients by reusing treated wastewater. [1,2].
Constructed wetlands in Bayawan City
https://www.wetlands.ph/projects/conference_wetlands-climatechange-biodiversity/exposure-trips/bayawan-wetland/
Overview
Nature-based solution
- Blue infrastructure
- Coastal wetland, mangroves and salt marshes
Key challenges
- Coastal resilience and marine protection (SDG 14)
- Coastal protection / hazard mitigation
- Water management (SDG 6)
- Improvements to water quality
- Health and well-being (SDG 3)
- Improving physical health
- Inclusive and effective governance (SDG 16)
- Effective management
- Social justice, cohesion and equity (SDG 10)
- Environmental education
Focus
Creation of semi-natural blue areas
Project objectives
The project had several objectives, including:
- Protecting coastal waters from pollution caused by domestic wastewater
- Improving residents' health by providing safe sanitation and wastewater treatment facilities
- Showcasing the effectiveness of constructed wetlands
- Promoting the use of locally available reeds for effluent filtration
- Conserving water and nutrients by reusing treated wastewater [1,2,3]
Implementation activities
Bayawan was the first city in the Philippines that have implemented the constructed wetland technology in treating domestic wastewater. [3]
In April 2005, the City Government of Bayawan collaborated with the German Technological Agency (GTZ), Oekotec GmbH, Worldbank, and Manila Water to assess the sanitation conditions in Bayawan and identify suitable design parameters and location for the constructed wetland [1]. The wetland was designed to cater to the needs of 3,000 people, living in 600 one-family houses, with an average of 5 people per household, and a Biological Oxygen Demand concentration of 300 mg/l, using a flow rate of 50 liters per person per day. To ensure maximum treatment efficiency, a combination of a vertical and horizontal vegetated soil filter was employed, using locally available Phragmites karka reeds as the filtering plant, which also served as an odor barrier during the filling process. These plants were grown during the construction phase in a nursery at the relocation site. [1] The wetland construction was carried out by the City Engineering office from May 2005 to August 2006, and the facility was inaugurated in September 2006. The wetland has been in operation since then, with regular influent and effluent analysis by the local water service provider [1,2]. Furthermore, social preparation activities like meetings and seminars were conducted to educate the future inhabitants of the relocation area [1].
The constructed wetland was deemed to be a low-maintenance technical solution for wastewater treatment that was easy to construct. The combination of a vertical soil filter and a horizontal soil filter yielded excellent results in terms of BOD removal and nitrification, as evidenced by regular monitoring of both raw and treated wastewater. Nonetheless, in order to meet the standards for drinking water, the treated water still needed to undergo complete disinfection treatment. [3] Additionally, some local residents reported detecting a foul odor emitted during the discharge of untreated effluent into the treatment pond. To address this problem, the facility management decided to discharge the untreated wastewater into the reed bed at night. As part of the maintenance work, the reeds are cut gradually to maintain some standing reeds as wind buffers while ensuring the constructed wetland's efficiency. [3]
Main beneficiaries
- Local government/Municipality
- Citizens or community groups
Governance
Management set-up
- Government-led
Type of initiating organisation
- Local government/municipality
Participatory approaches/ community involvement
- Consultation (e.g. workshop, surveys, community meetings, town halls)
Details on the roles of the organisations involved in the project
The construction of the wetland in Bayawan was initiated and funded by the city. The technical expertise of several organizations, including the German Technological Agency (GTZ), Oekotec GmbH, Worldbank, and Manila Water, was utilized in the initial assessment of sanitation conditions in Bayawan and the evaluation of the location and design parameters for the wetland [1]. The constructed wetland in Bayawan City has an environmental compliance certificate and as part of the certification process, it underwent community consultation. [3] Researchers from Silliman University were involved in the project to investigate the facility's efficiency and community perception. [3]
Project implemented in response to ...
... an EU policy or strategy?
Unknown
... a national policy or strategy?
Yes
(Bayawan City ventured into a constructed wetland in response to the government’s requirement to establish a wastewater treatment facility for the discharges of the city’s resettlement project. The project was implemented in compliance with the Clean Water Act, PD 856 (Sanitation Code of the Philippines) and RA 6541 (National Building Code of the Philippines).
)
... a local policy or strategy?
Unknown
Financing
Total cost
€100,000 - €500,000
Source(s) of funding
- Public local authority budget
- Research organisation / University
- Multilateral funds/international funding
Type of funding
- Earmarked public budget
- Direct funding (grants, subsidies, or self-financed projects by private entities)
- Loan
Non-financial contribution
Unknown
Impacts and Monitoring
Environmental impacts
- Environmental quality
- Improved waste management
- Water management and blue areas
- Improved water quality
- Enhanced protection and restoration of coastal and marine ecosystems
Economic impacts
- Reduce financial cost for urban management
Socio-cultural impacts
- Social justice and cohesion
- Improved liveability
- Health and wellbeing
- Improved physical health
Type of reported impacts
Achieved impacts
Presence of formal monitoring system
Unknown
Presence of indicators used in reporting
No evidence in public records
Presence of monitoring/ evaluation reports
No evidence in public records
Availability of a web-based monitoring tool
No evidence in public records
References
[1] Sustainable Sanitation Alliance (2010). Case study of sustainable sanitation projects. [online] Available at: Source link [Accessed 16 Feb. 2023].
[2] Society for the Conservation of Philippines Wetlands, Inc. (2009). NCWCCBC -Exposure Trip to Bayawan Wetland – The Society for the Conservation of Philippine Wetlands, Inc. [online] Society for the Conservation of Philippines Wetlands, Inc. Available at: Source link [Accessed 16 Feb. 2023].
[3] Guinoo, R. S. II, Aguilar Jr., A.S. & Oracion, E.G. (2009). The efficiency and social acceptability of the constructed wetland of Bayawan City, Negros Oriental. [online] Researchgate. Available at: Source link [Accessed 16 Feb. 2023].
[2] Society for the Conservation of Philippines Wetlands, Inc. (2009). NCWCCBC -Exposure Trip to Bayawan Wetland – The Society for the Conservation of Philippine Wetlands, Inc. [online] Society for the Conservation of Philippines Wetlands, Inc. Available at: Source link [Accessed 16 Feb. 2023].
[3] Guinoo, R. S. II, Aguilar Jr., A.S. & Oracion, E.G. (2009). The efficiency and social acceptability of the constructed wetland of Bayawan City, Negros Oriental. [online] Researchgate. Available at: Source link [Accessed 16 Feb. 2023].
Information about this nature-based solution was collected as part of the "NBS 2022" UNA Asian extension project funded by the Asia-Europe Foundation.