WaveSave's Portable Rubber Dam Offers Rapid Flood Defense as Climate Risks Grow

SlamDam is designed to be installed in the early hours of a flood. A user unfurls the barrier on the ground along a riverbank or shoreline and pumps it full of water until it swells into place, standing up to 1.3 meters high and shielding nearby property and structures. Developed in the Netherlands in 2013, it was initially tested and is still used by regional water authorities there. WaveSave, founded in 2017 and headquartered in Eindhoven, has since expanded into Africa and Southeast Asia, and customers have now deployed SlamDam in at least a dozen countries.

One in five people globally are at high risk of serious flooding, according to the company, and many live in communities without proper protection who cannot afford to evacuate or relocate permanently. By one estimate, nearly 2 billion people will be exposed to floods by 2100, an increase of 300 million from 2020, driven by climate change and population growth. SlamDam is intended to protect farmland and personal property as well as critical facilities such as hospitals and water treatment plants.

The barrier is cheaper in the short term than permanent measures such as building levees or rebuilding facilities on higher ground, and its temporary nature means it can be deployed as needed and then stored away. With a lifespan of more than 40 years, the barriers can be reused. For freshwater floods, residents can tap the water stored inside the mobile dam to irrigate crops in the weeks and months afterward, which is particularly useful during dry seasons or in drought-prone regions. At the rural Mpanda commune in Burundi, where a SlamDam was deployed during the 2022 flood season, farmers with access to the stored water produced more crops that year and doubled their incomes, according to a UN report.

Companies including AquaFence, MegaSecur and NOAQ Flood Protection also make mobile flood barriers. WaveSave says it distinguishes itself partly by focusing on rapid emergency deployment in developing countries and by emphasizing SlamDam's ability to store water for later use. But a research team that analyzed SlamDam's use in Kenya found a series of challenges to getting communities there to adopt the technology, including figuring out who should own and deploy the dam and the upfront cost. A SlamDam costs between €1,000 and €3,000 (about $1,140 to $3,400) per five-meter section and comes in a range of heights; protecting a single entrance to a home or facility might require only 10 meters, while surrounding a facility or shielding a farm or neighborhood might take 200 to 300 meters. The price is still too high for many communities or farmers.

WaveSave's managing director, Omar Saleh, says the company is looking into offering SlamDam as a service and deploying it on demand to make protection more affordable. All SlamDams are currently manufactured by an external partner in the Netherlands and then shipped to customers based elsewhere. WaveSave aims to open a local production facility for SlamDams in Southeast Asia in early 2027, followed by a similar facility in East Africa, which could help lower costs. The company recently won contracts for four new projects totaling about $5.3 million in Burundi, Djibouti and Guinea, with a "substantial pipeline" developing in Southeast Asia and Latin America, according to Saleh. WaveSave is currently self-financed and has seven employees. Saleh says he plans to grow organically by investing profits back into the firm, part of which will involve offering new services such as advising communities on how to install and operate simple, off-the-shelf rainwater harvesting systems.