Stone Arch Bridge Technology
Kasese District Local Government

A. Problem Analysis

 1. What was the problem before the implementation of the initiative?
Kasese District, in Western Uganda, has a large road network of 2831 KM of which 400 Km are National Roads, 1831 Km are Community Access Roads, 389 Km are District feeder roads and 211 Km are urban roads. Community Access and District roads are constructed and maintained by the Sub counties and District respectively. Kasese district has many rivers, streams and swamps originating from Rwenzori Mountains. These streams and rivers are often flooded making it extremely difficult to cross. The floods also wash away the few wooden bridges, making the situation even worse. Each financial year, the District and lower local governments are faced with funding constraints making rural transport challenges overwhelming. The limited available road funds are spent on costly public procurement of a few structures and road repair while most of the grassroots requests remain without support. Rural roads are often designed with an insufficient number of culverts due to the high cost of concrete culverts. It causes inadequate drainage and premature erosion, leading to increased maintenance costs of the road network. Due to budget constraints, wooden bridges are constructed with a limited lifespan of 4-10 years and the need for constant repairs. The District, on average, receives Uganda Shillings 800 million (USD 223,000) annually for road construction and maintenance, including bridges. Moreover, the conventional reinforced and steel bridges are very expensive. A reinforced concrete bridge of 13 metre span cost Uganda shillings 446 million (Nkonko bridge in Karusandara Sub-county). An innovation was required because the situation was getting out of hand. Lack of bridges cut off large communities from markets, business, schools, health centres, churches, mosques and social networks. A number of school going children would go to school when the streams were dry and stop during the rainy season resulting into high absenteeism and dropout rate. The traditional reinforced bridges were very expensive due to high cost of iron bars and collusion by private construction firms. In spite of this, budgets for roads and bridges were going down. Life for citizens was so pathetic that something had to be done and it was clear the solution could not come from anywhere else but from within the district. The stone arch innovation was initiated by the district engineering department as the only way to provide more bridges at a declining budget allocation to help improve livelihood in rural Kasese. There was need to address the problem of poor connectivity. Due to lack of bridges across rivers and swamps, some children could not access schools; the sick could not access health centres; farmers could not access markets; and families were disconnected especially during the rainy seasons. Bridges were expensive to construct and yet the district collects very little revenue and relies on grants from central Government, which are minimal. These issues were of public concern because it’s the role of Government to provide good health, education and economic opportunities to its citizens. Yet under the circumstances, the population was so vulnerable and in dire need for change in conditions. These circumstances affected the majority of the 702,029 people in Kasese given that 75.5% of them live in rural areas. The rural poor, women and school going children were the most affected. Other issues to be addressed were lack of political will to embrace the innovation as well as lack of will from technical staff especially in procurement unit as they thought this would interfere with their work and may lose some kick backs.

B. Strategic Approach

 2. What was the solution?
 The project initiative was the construction of Stone Arch Bridges across rivers, streams and wetlands thus connecting the rural poor, youth and women to markets, schools and health centres.  The bridges use locally available resources in rural areas i.e. stones, sand, cement and human resources all of which are abundant.  The bridges are an innovation because they withstand the frequent flooding in the mountainous Kasese, have long lifespan and reduce the cost of bridge construction by 70% to 84% compared to usual reinforced bridges.

 3. How did the initiative solve the problem and improve people’s lives?
The construction of Masonry stone arch bridges and culverts started in 2011. Prior to that the District Poverty Reduction Programme (KDPRP) funded by Belgium Technical Cooperation (BTC) financed the Construction of reinforced concrete bridges. In 2011 and 2012, BTC supported construction of 4 reinforced concrete bridges at a cost Shs. 1.2 billion. In the same period, they supported the masonry stone arch bridges and constructed 11 bridges of similar span and in similar conditions at a cost of Shs 110 million. It was evident that the initiative cuts the cost of bridge construction by over 70% compared to reinforced concrete bridges. The problem of limited budgets has been partly resolved because these bridges are very cheap, saving 70-84% of bridges construction cost when reinforced bridges are used. The masonry stone arch bridges use cheap locally available materials i.e. stones, sand, cement and community labour. The communities collect the stones which have been deposited by floods. Sand is abundant in the area and labour is readily available. It was only cement that was bought. This helped to lower the cost of bridge construction. For instance, Kanyampara triple arch culvert of span 5m cost Shs. 6 million while Kanyamunyu Reinforced box culvert of span 5 m and same site conditions cost shs. 110 million. In the economic environment of East Africa, with low labour costs and high costs of industrial building materials, stone arch bridges provide an affordable and practical option which can be implemented in a wide variety of settings. Because of a lower cost, more bridges were constructed in rural poor and hard to reach areas. Many sub counties were able to construct at least a bridge each year hence increasing the cost-benefit ratio for low cost bridges/culverts serving a large population. This increased accessibility to rural farmers such that the buyers were able to reach the farmers directly without using intermediaries who reduce their profit margins. Farmer’s production increased leading to increase in farm income through sale of their produce to direct buyers. Food security also improved due to increased production. The stone arch technology is strong because they are resistant to strong floods which are common in the region. The bridges are rugged and therefore reduce the rate at which the floods wash away the bridges. They are durable compared to reinforced bridges. This reduced bridge maintenance cost and disruption of communities due to broken bridges. The adoption of stone arch bridges has enabled the district and lower local governments to improve the access to social services especially health centres, schools and markets which are frequently used by women. Rural markets have expanded in areas where the bridges were constructed. They are a low-cost appropriate technology for rural areas because they are cheaper to construct and maintain. The development of stone arch bridges in Kasese District has attracted other development like low cost Stone Masonry Mini Irrigation which Ministry of Water & Environment has got interested in and has planned for some low cost irrigation schemes in Uganda. These have used stone arch technology to provide water for farming for the rural poor since accessibility to farms and project area is guaranteed.

C. Execution and Implementation

 4. In which ways is the initiative creative and innovative?
The project initiative is a shift from the traditional way of construction of bridges by Local Governments in Uganda. It is unique in the following ways;  It is a new bridge product previously not known in the Ugandan road sector.  The innovation uses local resources: stones, sand, cement and local manpower as replacement for steel, aggregates and concrete which are expensive.  Low cost technology, saving 70-84% of the bridge construction cost, hence enabling the District to build more bridges with the same or even smaller budgets. This has enabled the district to connect more rural communities to economic and social opportunities and hence fighting poverty  Too much labour intensive and hence not mechanized thus utilizes local abundant labour  The bridges are strong, long lasting and are associated with low maintenance costs. They with stand strong floods from the Rwenzori mountains and enhance road safety  This technology avoids the lengthy procurement processes since most of the materials are collected by communities. The few procured resource use Force on Account which uses direct procurement. It shortens bridge construction period

 5. Who implemented the initiative and what is the size of the population affected by this initiative?
The initiative is implemented by Kasese District Local Government under Works Department headed by Eng. Baluku Richard, a Senior Civil Engineer. The first 11 stone arch bridges were funded by Belgium Technical Cooperation through Kasese District Poverty Reduction Programme (KDPRP) in 2011 and 2012. From 2013, the district Works department took over and now manages the initiative. The department receives requests from sub counties to go and support them and build the bridges. Since then, more masonry stone arch bridges have been built by other Districts and Ministry of Works & Transport for study purposes The technology is serving a great number of rural poor and vulnerable population. It is estimated that over 500,000 people have benefited directly and indirectly from stone arch bridges. The project was implemented in 11 sub counties with a population of 380,000 people. More bridges have been brought on board benefitting an additional 70,000 people. It is estimated that an additional 50,000 from other sub counties, Municipal Council and other parts of the country are served by the bridges. In all, school going children, farmers, traders, teachers, medical workers, patients, administrators, tourists, transporters, and other people have benefited from the bridges. The project has benefitted rural poor and hard to reach areas with increased accessibility. Of particular importance, farmers now deal directly with produce buyers which has minimized the role of intermediaries thereby increasing farmers’ economic margins and hence more production. Other crucial developments originating from masonry stone arch bridges include low cost stone masonry mini irrigation schemes eg Muhokya mini irrigation scheme in Kasese.
 6. How was the strategy implemented and what resources were mobilized?
For local masons first exposed to arches, the concept remains abstract and shaky. The structure is completely unstable until the two spans meet in the middle and the arch is closed. From a layman’s perspective, it is hard to see how a bridge merely built with stones will support heavy traffic. The construction principle is clearly illustrated as below; A preliminary survey is done to give a quick insight into the cost of the construction and the willingness of the community to contribute. Based on this data, the number of potential bridges in terms of the cost and the priority sites are identified. The relevant sub county (lower county local government) then makes a selection of the bridge to be constructed. Works department of the district prepares the designs for the stone arch bridge as well as cost estimates for the bridge project. The cost for community contribution in terms of providing stones or sand is also computed. Payment for the work was done by the Chief Administrative Officer, Kasese on basis of payment certificate prepared by works department. The mode of implementation was contract method as well as Force on Account method. Contract method requires obtaining a Contractor to execute works while Force on account method requires the staff of the Works Engineering department of the district to execute the work themselves. Of the 11 bridges, only one bridge (Kalibo bridge in Kilembe sub-county was on contract basis and cost Shs. 30 million while the rest where on Force Account. After comparing the cost, Contract method was dropped and all the 10 bridges as well as those constructed after were by the district staff. Four Masons where provided and guided by a fulltime site engineer from works department of Kasese District local Government. The community helped in collecting stones and sand and these were mainly women and youth. Technical Supervision was done by Kasese District Department of Works Engineers (Senior Civil Engineer/Road Engineer and Assistant Engineer) alongside BTC staff (Project Engineer and Technical Advisor- BTC). The financial costs went into purchasing mostly cement. In some cases, sand and stones were bought but only in those places where they did not exist locally. In most cases, sand and stones were collected and provided by the communities. The technical costs in terms of conceptualization and preparation of designs were not known. The district engineers who earn a salary produced these itmes The following examples show a comparison of costs between stone arch bridges and the traditional reinforced bridges: SN Name and type of bridge Span Cost in Uganda shillings Cost saving 1 Kaghema bridge Reinforced 8 m span 298,000,000 84% Kalibo Stone Arch bridge 8 m span 39,000,000 2 Kanyamunyu bridge Reinforced 4 m span 116,000,000 83% Kakone stone Arch bridge 5 m span 20,000,000 Generally, masonry stone arch bridges/culvert are cheaper compared to conventional reinforced concrete bridges/culverts with a huge cost saving as shown above The project was funded by Belgium Technical Cooperation through Kasese District Poverty Reduction who provided 90% (Shs. 100 million) of the total cost. The balance was funded by Kasese District Local Government and the local communities provided the balance of 10% (Shs. 10 million). The local community contribution was in form of stones, sand and water which was usually close to 10%. When BTC project ended in 2012, sub-counties started funding the stone arch bridges. So far 5 stone arch bridges have been constructed and 2 are ongoing in the sub-counties of Bwera and Maliba

 7. Who were the stakeholders involved in the design of the initiative and in its implementation?
The Works department of Kasese District headed by Eng. Baluku Richard was the key players in the project. Senior Civil Engineer, Baluku Richard, prepared the design of the initiative and advised the Chief Administrative Officer that stone arch technology was a real and correct substitute for reinforced concrete bridges since it was cheap in terms of cost and that all construction materials were locally available given the mountainous nature of Rwenzori region in Uganda. The Chief Administrative Officer accepted the idea. The Engineer and Chief Administrative Officer then brought the idea to the Political wing of the district headed by the District Chairperson (Lt.Col. Mawa Muhindo)and four Executive Secretaries (including Secretary for Works). The Chairperson and Executive embraced the idea. It is important to note that the former political wing headed Rev. Julius Kithaghenda refused the proposal on condition that it was an old mode of doing things since we were in modern times. The Kasese Poverty Reduction Programme (KDPRP) with support from Belgium Technical Cooperation funded the proposal since their first attempt to introduce the technology was refused by the then political wing under Rev. Julius Kitaghenda. The local communities also played a major role in the project. The communities formed Infrastructure Management Committees which were instrumental in guiding the project. The communities also provided stones and sand to the project. In conclusion Eng. Baluku Richard conceptualized, sold the idea to technical and political leadership, designed and implemented the project. He has made presentations on the project in Uganda Government and to delegation from the region. The initiative won the 2nd Public sector innovations Awards in 2013

 8. What were the most successful outputs and why was the initiative effective?
When the initiative started in FY 2011/2012, 11 stone masonry arch bridges were constructed at a cost of Shs.110 million compared to 4 reinforced concrete bridges constructed at a cost of shs 1.2 billion. This laterally meant that a stone arch bridge cost averagely shs 10 million compared to an average cost of shs.300million of Reinforced Concrete Bridge in the Rwenzori Region. This data reflects over 95 % cost saving with the same strength of accommodating 40 tons since the bridges are built in low traffic areas of less than 20 Vehicles per day and on small streams of less than 2000Km2 and span not exceeding 20 m with width of 5m. Improved local economic development has been realized in the rural poor sub-counties eg the Construction of Kanyampara masonry triple arch culvert has lead to accessibility of farmlands in the rural munkunyu sub-county and therefore development of a mini stone masonry irrigation scheme has started in the sub-county to serve about 5600 households. The project is expected to turn the sub-county into a food basket capable of supplying food to Kasese District, Uganda, Neighboring DR Congo, Rwanda and Burundi, and avert any food shortages they may occur due to high influx entry of refugees. Women and youth have been involved in the search for local materials especially stones. This has offered employment to women during the construction. Not highly skilled masons have been trained to construct stone arches hence employment to the local population. Eng. Baluku Richard has successfully disseminated information to Ugandan Local Governments and beyond, including the academia world which has proved that the technology is transferable to other rural poor parts of the world with keen involvement of women and vulnerable youth for local labour employment purposes

 9. What were the main obstacles encountered and how were they overcome?
The main obstacle was resistance. The political head of the district initially rejected the idea calling it obsolete. There were many who did not like the idea for instance the procurement unit of the district. It took time to convince many that it works. We overcame this problem through engagement. I convinced members of my department and all agreed it will work. We engaged the Chief Administrative Officer and the Political Head and the Executive. Eventually all those who matter spoke for us Another challenge was shortage of skills. It was a new concept and very difficult to understand how stones connected together with sand and cement can support a 40 ton vehicle. The Works department has one Engineer and very few support staff. The technicians found difficulty in implementation of stone arch technology especially load assessment capacity for the stone arch bridge. To solve this problem, we adopted simple methods for assessment. We used MEXE method since it does not involve calculation of moments. Furthermore, we trained Masons in construction of the stone arch bridges. In every new area, we would take one experienced mason who would train three others as the construct the bridge. This enabled us to create a critical mass of masons. Shortage of funds to finance the project. The district didn’t have enough money to fund the project. The Works department decided to allocate 2 stone arch bridges each financial year after closure of BTC project due to lack of funds. We resolved this problem by seeking funding from BTC which provided 110 million. The local communities also co funded the project by providing sand and stones in kind.

D. Impact and Sustainability

 10. What were the key benefits resulting from this initiative?
The technology has improved community engagement. Infrastructure Management Committees (IMCs) have been formed in villages where stone arch bridges have been constructed. It’s mandatory to have women, girls and youth on the Committees. This improves sense of ownership of the project and thus maintenance and protection of the project after completion becomes communal responsibility guided by the Infrastructure Management Committee put in place. The initiative has lead to increase in bridge asset in the district. Before introduction of the initiative, the district had 7 bridges. Currently, the district has over 23 bridges and 2 are currently under construction. Over 76% of the district bridges are stone arch. This has improved accessibility in the remote areas. Improved accessibility has lead to improvement in farm production. Although no impact study has been carried to quantify the farm production before and after, it is visible that fresh vegetables like cabbages, tomatoes and other commercial crops like especially rice and onions are on the increase. Previously, most of these crops used to be brought into the district from neighbouring districts largely Bushenyi and Rubirizi. This trend is rapidly changing with a lot of horticultural produce in Kasese town coming from rural Kasese due to improved accessibility. More rural poor and vulnerable groups have been connected to each other by these bridges hence improved economy. Bridges have improved school enrolment. Notable schools where enrolment has increased as a result are Bunyandiko Primary School in Kilembe Sub County and St. Andrew Primary School in Munkunyu Sub County. Previously, it was difficult for children to cross rivers and streams especially during the rainy season. Now children cross to schools using the bridges leading to reduction in dropout rates. The stone arch bridges are cost effective. The cost effective bridge construction is reduced by over 70% and up to 95% compared to reinforced concrete bridge structures. Since the technology is highly labour intensive and involves use of available local materials, employment to the rural poor is guaranteed during the period of construction which is usually 1-2 months. For example in Bwera Sub County where a bridges is currently under construction, 4 youthful masons are working on the bridge while 10 women and 5 men collect stones and sand

 11. Did the initiative improve integrity and/or accountability in public service? (If applicable)
The initiative has diminished procurement related corruption and improved integrity. With the initiative, the District uses Force on Account. This is a system where the District resources are used in-house without using external contractors. In this case, the District uses its human resources to construct the bridges. Many bidders for road projects inflate costs because of hidden commissions. They were now excluded from this project. Possible corruption from the District human resources has also been dealt with through use of Infrastructure Management Committees. The Committees meet weekly to review the activities. They mobilize communities to oversee the activities of collection of materials and construction of bridges. They monitor quality of work which improves transparency. The costs involved in the construction are also made public to the communities. They make public accountability during and after the construction of each bridge. The above examples shows that accountability is increased since the local community is involved from the start and that more stone arch bridges are constructed at a cheap cost since rural local materials are cheaper compared to the industrial materials.

 12. Were special measures put in place to ensure that the initiative benefits women and girls and improves the situation of the poorest and most vulnerable? (If applicable)
Construction is simple, and therefore uses low-skilled labour to implement the work. Unskilled workers from the villages collect stones and sand; masons build the bridges; and village carpenters make the simple scaffolding that is needed. It promotes employment, focusing on people and their skills rather than machines and imported cement and diesel. Mostly women & girls and male youth are involved to collect stones and as masons. In cases where a village has no masons, a skilled mason is brought it to train three from the village who then work with him on the bridge. This approach enabled also the involvement of the rural communities and district councils during the planning and execution of road works which resulted into a greater sense of ownership, self-reliance and community cooperation. The execution of the works is delegated to village road committees and villages access donor and government funding for road works through the merging of local resources. This approach favours the adoption of stone arch bridge technology not only by communities but also by local governments. The district allocates road funds basing on effective community contribution. More funds are allocated where grass root communities are more involved.

Contact Information

Institution Name:   Kasese District Local Government
Institution Type:   Local Government  
Contact Person:   Baluku Richard
Title:   Head of Roads, Bridges & Buildings  
Telephone/ Fax:   +256 783 492426
Institution's / Project's Website:  
Address:   Kasese District Local Government, Roads & Engineering De
Postal Code:   +256
City:   Kasese Town
State/Province:   Western

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