Project Background
To support the continued implementation of the Overall Improvement and Adaptation Plan for River Basins under Central Government Jurisdiction, the Water Resources Planning Branch previously developed a reference manual for overall river basin improvement and adaptation planning. Following its practical application in various river basin projects, the planning framework has demonstrated its effectiveness and value in advancing integrated watershed management and climate adaptation policies.
To further advance these policies, the approach will now be extended to regional drainage systems, with greater emphasis on detailed and integrated planning at the catchment scale.
Accordingly, this project aims to develop a reference manual for the overall improvement and adaptation of regional drainage systems under central government jurisdiction. While building on the existing framework for river basin planning, the manual will address the distinct characteristics and smaller spatial scale of regional drainage catchments.
In view of the growing uncertainty associated with climate change and emerging social challenges, the manual will also incorporate concepts related to emerging technologies and innovative approaches, while promoting evidence-based governance to strengthen risk management and improve the quality of decision-making.
Project Objectives
The project assesses the flood protection capacity of regional drainage catchments under climate-change risk scenarios, identifies areas of potential risk, introduces risk-management concepts, and develops appropriate climate-change adaptation measures.
In addition to flood risk management, the planning process considers habitat and environmental conservation, waterfront landscapes, water culture and history, and the enhancement of natural landscapes to improve the overall quality of water environments.
The project seeks to realize the vision of “Evidence-Based Adaptation for Sustainable Water Environments.”
Main Activities
1. Catchment-Based Integrated Planning
The entire regional drainage catchment is used as the basic planning unit. Planning integrates the upstream, midstream, and downstream areas together with land use, water resources, and flood management. Through coordinated engineering and management measures, the project seeks to optimize the overall water environment, flood safety, and water-resource utilization of each catchment and strengthen its resilience to flooding and climate change.
Within this framework, improvement and adaptation are defined as follows:
- Improvement: Measures addressing deficiencies in existing flood-risk management or previously incomplete works. For example, drainage improvement projects may continue to be implemented in accordance with approved management plans or the results of planning reviews.
- Adaptation: Measures developed in response to potential climate-change risks to enhance disaster resilience and enable communities to better coexist with flood risk. Examples include incorporating runoff allocation and Local Flood Retention into land-use planning so that both waterways and land can share and accommodate floodwater.
2. Resilient and Nature-Based Flood Management
The planning approach moves beyond conventional waterway-centered management and traditional gray infrastructure. Instead, it promotes greater flood resilience through an approach that places equal emphasis on infrastructure, management, and governance.
Building on the concept of Nature-based Solutions (NbS), ecosystem services are incorporated into the overall planning process to promote flood-management strategies that work with natural processes and create a better balance among water, nature, and people.
3. Integrated Planning across Multiple Sectors
The planning framework is organized around four major themes:
- Waterway risk
- Land Flooding
- Blue-green network conservation
- Waterfront connectivity and integration
Public participation is incorporated throughout the planning process. Planning for the upstream, midstream, and downstream areas of the catchment is coordinated with national spatial and coastal planning, while cross-sectoral collaboration links a range of measures, including waterway management, coastal management, runoff allocation, outflow control, Local Flood Retention, water culture, waterfront integration, the Taiwan Ecological Network, and blue-green network conservation.
4. Bottom-Up Adaptation and Public-Private Collaboration
The project adopts a bottom-up approach to strengthen the ability of land and communities to respond to existing and future risks and to develop adaptation measures for climate change.
The planning process also seeks to reflect the public’s expectations for water environments and the relationship between people and water.
Public-private collaboration and stakeholder participation are therefore important components of the planning framework. Effective communication mechanisms will be used to build mutual trust and consensus, based on the principles of information transparency and equal participation.
5. Integration of Planning and Risk-Management Processes
The overall improvement and adaptation planning process includes four major stages: data collection, issue identification and assessment, development of strategies and measures, and recommendations on roles and responsibilities.
Data collection includes relevant studies and reports on risk assessment, drainage management planning, runoff allocation, and other related topics.
The reference manual will establish an integrated framework linking existing drainage management planning, runoff allocation, risk assessment, and adaptation planning. Through this framework, existing planning tools and risk information can be systematically incorporated into the development of improvement and adaptation strategies for regional drainage catchments.