The smooth ride was over.
Turning off the flat, black pavement of the national road, I bumped along increasingly remote and rutted dirt roads for the next 40 minutes. Local children, now accustomed to my dusty white Toyota HiLux, gleefully sprinted behind me, hoping to sneak a precarious ride on the tailgate of my pickup. As the dirt track descended, steep hillsides gave way to a small valley of maize, beans, potatoes and other staples of the Rwandan diet. In the distance, familiar silhouettes of my team came into focus, waving warmly as I pulled up to my destination: our bridge project.
As country manager for Denver-based Bridges to Prosperity’s Rwanda Program in mid-2013, I’d spent the past five weeks directing construction of the substructure for a cable-supported pedestrian bridge that would span the Muregeya River in western Rwanda. Over the past century, that river’s seemingly innocuous flow had cut a deep channel that snakes through the valley. Decades ago, colonial Belgian engineers had built weirs to control the river flow and grow food in the fertile soil. But those barriers are mere relics now.
Today, the river is just one more challenge to the local population that is already surviving at the margins. When the water is low, children strip off their school uniforms and hold them high over their heads as they hop through the murky, waist-deep water. When the water is high, only the most determined go to school. Every year, the river claims lives. Spanning 51m across, the new bridge will connect two districts and provide safe access to healthcare, education, and commerce, for tens of thousands of villagers.
ARUP’s Kayin Dawoodi was named UK’s Young Engineer of the Year for his work with B2P in Western Rwanda. The project “changed the lives of thousands of people in the area and shows how vital engineering is – and how much we take it for granted at home,” he said.
Granted, this may seem an odd opening scene for a technology commentary, but Rwanda is a land of contrasts. A dark, tragic past, to be sure, but now facing a bright future. Steep, verdant hills abut a burgeoning capital city. It is a place where miles away from any power lines, you can still encounter an eager teen that asks to friend you on Facebook. Therefore, technology in my work is a juxtaposition of two opposing forces.
On one hand, simplicity is key. The easier a robust bridge is to build, the more likely it is to be adopted by local engineers. Work is done with pickaxes, shovels, and lots of hands. Yet, at the same time, we are building in the 21st century, and technology plays an essential role in achieving safe access for isolated rural communities. From selecting bridge sites, to developing the span’s design, to monitoring its efficacy, the technical work still employs modern technology in areas where you feel like you are stepping back in time.
Simple Solutions, Aided by Tech
B2P’s Rwanda Program has served as a proving ground for the fusion of simplicity and technology in the nonprofit’s mission to eliminate poverty wherever its root cause can be traced to isolation. In that sense, the Muregeya Bridge is a classic example of the major good that can be accomplished with a simple span.
The first step in a project like the Muregeya Bridge is to identify locations where safe river crossings are a high priority to the local community. In Rwanda, the government is strong and closely integrated with the people, meaning that site identification can be done through engagement of local leaders. After collecting GPS coordinates, basic population statistics, and other information for each site, the data is organized using geographic information systems (GIS) software. High priority areas are then targeted for bridges. Finally, satellite images and basic ground surveys are used to select a safe, sustainable location for a bridge.
Next, the bridge design. This is where a partnership with London-based Arup enabled the project to make large strides. Arup allowed several of its top bridge engineers to commit time to B2P in order to develop a tool that would simplify the bridge design process, a tool that local engineers could use to generate robust suspension bridge designs with basic inputs. The result was BridgeTOOL, a software and construction manual system that created full design solutions intended to bring expertise from one of the world’s top design firms to the rural hills of Rwanda on a scalable basis.
With the use of BridgeTOOL, we were able to reduce design times dramatically while still producing bridge designs that could be constructed without heavy equipment. The Muregeya Bridge project would be a “ground-truthing” exercise for the program that would allow Arup’s engineers to tweak the tool before it was fully incorporated into B2P’s suite of bridge-building resources.
Monitoring, maintaining, sustaining
A final but critical melding of simplicity and tech comes in the maintenance and monitoring of the bridges. In an effort to quantify the impact of rural pedestrian bridges on local communities, B2P is in the process of conducting pilot studies that use 3G mobile sensors developed by the Sustainable Water, Energy and Environmental Technology Laboratory (SWEETLab) at Portland State University to collect traffic counts. Motion detectors record when a villager crosses the bridge, and data packets are uploaded to a central server via the 3G connection. If the pilots are successful, the Muregeya Bridge will also feature a wireless traffic count system.
My site visit that day was a particularly joyful one. After weeks of crunching to meet a seemingly impossible deadline, our B2P team had successfully prepared the bridge site for the arrival of the Arup team. Steel towers (each 7m tall), cross braces, and crossbeams had arrived, fabricated by one of our strongest partners, Kigali’s Integrated Polytechnic Regional Centre (IPRC). The bridge’s substructure construction team, led by our head mason and interns from Duke and Princeton universities, had placed reinforcement in and poured (by hand!) more than 30 cu meters of concrete. Most importantly, the community that day was brimming with excitement for the new bridge. There was much work to do, but everyone knew we had made it to the first important milestone.
The following week, the team of eight Arup engineers arrived to assist in the completion of the bridge they had spent so long designing. They spent two weeks sweating and straining with the Rwandan community and B2P team to erect the towers, hang the cables, and install the bridge deck. In the end, our joint B2P-Arup-Rwandan team cut it close, but the bridge was completed on time and to the elation of the community. The span now allows a community of more than 30,000 Rwandans to move freely across the river at any time of the year, regardless of the weather, and without having to fear for their lives.
This fall, our goal of using technology in the pursuit of simplicity was recognized in London by the Institution of Structural Engineers at Structural Awards 2014. Winning the Sustainability Award, and receiving a commendation for Pedestrian Bridges, the Muregeya Bridge to me illustrates how engineers in wealthy nations can leverage technology to help poor communities build solutions that actually improve lives. And with the lessons gained on this project, the BridgeTOOL can now be adapted to be used in other communities where B2P works all over the world.
A former B2P employee (in good standing), the author is now a graduate student at Duke University. In 2010, he graduated from the University of Notre Dame with a degree in civil engineering.
The project was also supported by the Karongi District of Rwanda, and Rotary Clubs of Kigali-Gasabo, Rwanda; Newport News, VA; Smithfield, VA; and Boulder Valley, CO.
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