What will it take to have disaster-resilient roads?
Tuesday, May 09, 2023
A segment of Musanze-Rubavu road that was damaged by floods on May 3. The government will spend Rwf41 billion on rebuilding national roads, Rwf38 billion on bridges, and Rwf25 billion on inter-district roads that were affected. Photo: Courtesy.

Experts have recommended the construction of roads and bridges that are resilient to flooding and landslides.

The reaction follows the government's decision to spend Rwf41 billion on rebuilding national roads, Rwf38 billion on bridges, and Rwf25 billion on inter-district roads that were affected by the floods and landslides in the Northern, Western, and Southern provinces. Some roads were blocked for four days as a result.

ALSO READ: Rwf130bn needed to rebuild disaster-hit infrastructure.

"There is a need for roads that can withstand the impacts of weather and climate change. To achieve such resilience, joint efforts and coordination among institutions are required to conduct a feasibility study that outlines how roads and bridges should be constructed to be resilient to floods and landslides,” said Disaster and Natural Hazard Risk Manager and researcher, Jean Baptiste Nsengiyumva.

He stated that the design of roads and bridges should take into account the soil and climate characteristics of each area throughout the country.

"Environmental settings such as the topographic wetness index, elevation, soil type, soil moisture, lithological features, soil texture, and others should be considered, as all areas of the country are not the same. This should also be taken into account when choosing construction materials and quantities for a particular road,” he said.

Lithological features refer to the character of a rock formation, while soil texture refers to the content of particles of various sizes, such as sand, silt, and clay in the soil. The Topographic Wetness Index (TWI), also known as the Compound Topographic Index (CTI), is commonly used to quantify the topographic control of processes related to the study of the movement, distribution, and management of water on Earth.

"Effective and efficient water drainage channels, retaining walls and other facilities are highly needed,” Nsengiyumva said.

ALSO READ: City of Kigali to restore drainages to cope with floods.

About 315 roads, 389 bridges damaged in five years

At least 315 road sections and 389 bridges have been damaged by disasters since 2017, according to the analysis by the Ministry in Charge of Emergency Management.

In 2017, the disasters damaged 13 roads and 49 bridges.

Flooding and landslides destroyed 34 roads and 64 bridges in 2018 and 30 roads and 40 bridges were damaged in 2019.

The flooding and landslides damaged 154 roads and 103 bridges in 2020, and at least 48 road sections and 39 bridges in 2021.

ALSO READ: Nyabarongo overflows, Kigali-Muhanga road closed.

Last year, 72 road sections and 59 bridges were damaged. From January to April 20, 2023, the same disasters devastated 12 sections of roads and 35 bridges.

Last week on May 2, a one-night landslide and flooding alone damaged 14 national roads.

Need for $600m for climate-resilient roads and bridges

Rwanda’s transport sector is dominated by land transport. Transportation is mainly undertaken by road with a current classified road network consisting of national roads (2,749 km), district roads class 1 (3,906 km), district roads class 2 (9,706 km), and other unclassified roads. However, they have not yet been found to be efficient and resilient transport systems according to studies.

Rwanda’s 10-year climate action plan, whose implementation is set to begin in 2022, shows that the country will need $600 million to develop environmental and engineering guidelines for climate-resilient roads and bridges, as well as to reduce the length of roads vulnerable to flooding and landslides up to 2030.

ALSO READ: Understanding funds sources for Rwanda’s $11 billion climate plan

The climate-resilient roads are part of the Nationally Determined Contributions (NDCs) or climate pledges submitted to the United Nations Framework Convention on Climate Change (UNFCCC).

The country needs $5.3 billion through 2030 to adapt to the effects of climate change, of which investment in resilient transport systems makes up 11%.