Urban Waterscape Solutions for Flooding and Heat in Ormoc, Philippines

Challenge

Ormoc, Philippines faces floods, storm surges, landslides, and heat stress, worsened by climate change and settlement in riverine and coastal zones.

Solution

Apply a Local Climate Change Action Plan and the Urban Waterscape project, using water retention, green infrastructure, and elevated housing.

Overview

Ormoc is a coastal city in the Eastern Visayas region of the Philippines. It faces multiple climate-related hazards due to its river systems, low-lying coastal zones, and expanding urban areas. Frequent flooding, storm surges, landslides, and rising heat threaten livelihoods, infrastructure, and long-term urban development. Climate projections indicate a temperature increase of 2.3°C and an additional 220 mm of annual rainfall by 2050 (UN-Habitat, 2022) – these conditions are expected to intensify flood risk and strain urban systems.

In response, Ormoc has pursued climate change adaptation through local planning and climate-responsive urban design. These measures include development of a Local Climate Change Action Plan and implementation of the Ormoc Urban Waterscape project in partnership with UN-Habitat’s Building Climate Resiliency through Urban Plans and Design initiative. Together, these efforts apply nature-based and engineered solutions to manage water, address heat stress, and improve safety and living conditions in vulnerable urban areas.

Historical disasters illustrate the severity of these risks. Typhoon Thelma in 1991 triggered flash floods that caused extensive loss of life and damaged public infrastructure valued at more than PHP 230 million (Philippine Statistics Authority, 2017). Super Typhoon Yolanda in 2013 again caused widespread destruction. These events have had lasting socio-economic impacts, particularly for farmers and fishers whose incomes are highly sensitive to climate shocks. Poverty levels have increased as climate-related disruptions reduce agricultural productivity and fishing income.

Climate risks and urban vulnerability

Ormoc’s physical geography contributes directly to its climate vulnerability. River systems such as the Pagsangaan, Malbasag, and Anilao rivers drain through urban and peri-urban areas, increasing flood exposure during periods of intense rainfall. The city’s coastal location adds storm surge risk, while steep surrounding terrain heightens the likelihood of landslides. Urban expansion into flood-prone zones has increased the number of people and assets exposed to these hazards.

Flooding affects both residential and agricultural areas. Seventy-one villages, home to more than 109,000 people, are considered at risk of flooding (Philippine Statistics Authority, 2017). Climate change has amplified these pressures by increasing rainfall intensity and raising average temperatures, which contribute to urban heat stress and compound flood impacts. These combined risks pose ongoing challenges to public safety, housing security, and economic stability.

The Ormoc Urban Waterscape project

A central example of this approach is the Ormoc Urban Waterscape project in Barangay Can-adieng. The project focuses on the Lower Malbasag river area, a densely populated zone that includes 361 households, many of them informal settlers living in flood-prone conditions. The project addresses three interconnected challenges: flood management, storm surge protection, and urban heat stress.

Water management combines natural and engineered measures. Vegetation is used along riverbanks to stabilize soil and reduce erosion. Water retention terraces constructed along the coastline store excess water during heavy rainfall and provide protection from storm surges. Rain gardens and bioswales (vegetated, engineered channels designed to capture, treat, and infiltrate stormwater runoff) are incorporated to absorb runoff and reduce surface flooding by increasing infiltration.

Climate-resilient housing and urban design

Housing redevelopment is a major component of the project. In Purok 1, an informal settlement comprising 68 households, new homes are designed to reduce flood damage and heat exposure. Houses are elevated 1.1 m above ground level, allowing floodwaters to pass underneath during extreme events. Designs include rainwater harvesting systems, solar roofs, and features that support natural ventilation and daylighting, which reduce energy demand and improve indoor comfort.

These housing and infrastructure measures aim to improve safety and living conditions for low-income households while reducing climate-related losses. The project integrates community needs into design decisions and aligns adaptation with broader goals of sustainable urban development.

Acknowledgements

This report draws from work by UN-Habitat and the Ormoc local government, detailed in “Path to Climate Resiliency: Case Studies of Cities in the Philippines” (UN-Habitat, 2022) and “Case Study on the Path to Climate Resiliency – Ormoc” (International Climate Initiative). Acknowledgement is given to the original authors. Reported by IGES, edited and updated by AP-PLAT.