Sibu Cloudburst Masterplan
Sibu city, Sarawak is prone to frequent flooding due to its unique geographical location in a low-lying area near the mouth of Ranjan River. Heavy rainfall and tides cause the river water to rise and overflow into the surrounding land, damaging buildings, infrastructure, agriculture, and livelihoods of the people living in the affected areas.
The Government of Sarawak sought an innovative approach from Ramboll to tackle this complex challenge. What started out as a city plan for flood protection developed into an overall masterplan, which not only protects the city against flooding, but also provides further solutions towards liveability and improvements of the microclimate as well as water management to avoid further land subsidence.
Ramboll was contracted by LCDA to undertake a cloudburst masterplan for Sibu. The project aimed to identify opportunities for enhancing and complementing existing infrastructure by integrating blue-green infrastructure (BGI) and integrated planning (IP) into a comprehensive cloudburst masterplan to mitigate flooding.
The project unfolded in three stages, involving:
- A Flood Risk Assessment
- Developing a Conceptual Cloudburst Masterplan and Design Options
- and crafting a Conceptual Integrated Infrastructure and Urban Development Masterplan for Bukit Assek
Integrated planning and blue-green infrastructure (BGI) implementation were advised to mitigate flood risks, alongside studying the interface between high-risk river edges and planned protective measures like the polder dike, as well as other infrastructure elements like roads and setbacks.
Pritha Hariram, Ramboll’s director in water infrastructure and climate resilience for Asia Pacific, said: “we are proud to support our client to undertake this significant project in Asia Pacific. The integrated approach to addressing flood risks, combined with creating multifunctionality space and infrastructure, deemed as Cloudburst planning, is key in realising economic, social, and environmental benefits, creating a liveable and resilient urban environment for its residence and visitors alike.”
“Ramboll’s strong track record in blue-green infrastructure in the region and globally is enabled by our integrated and multidisciplinary capabilities in water, master planning, urban design, landscape design, civil & structure engineering, mobility and environmental advisory.” Added Pritha.
Ramboll’s approach will bring expertise across several sectors including: water, mobility, landscape, and urban planning to improve flood management through nature-based solutions and regenerative design, as well as fulfilling the city’s socio-economic development.
The conceptual masterplan is expected to be completed by July 2024.
Cloudburst planning and design has been implemented in major Western cities like Copenhagen and New York City, addressing extreme rainfalls in a modern and sustainable manner. However, this is the first time a city-wide Cloudburst plan has been implemented in Asia.
Cloudburst resiliency planning in its simplest form is about helping cities cope with the extreme rainfall events of the future caused largely by climate change. Importantly, the strategy tackles key flood management and water quality issues, but it also creates the greatest possible synergy with the urban environment. The solutions are therefore multifunctional, and the approach is nature-based.
What would previously have been a drainage channel could now, for example, become a community park that would also manage water overflow. This is a new generation of blue-green infrastructure that addresses climate change while also responding to community needs.