1. Bridges on Kapchorwa – Suam Road
Location Uganda
Client Ministry of Works, Housing and Communications, Republic of Uganda.
Cost tba
Firm Mott MacDonald
Services Feasibility Study and Detail Design
Completion December 1999
This route traverses the Mount Elgon National Park roughly in a 75 km
semicircle to the Kenya Border. The existing road having deteriorated to a mud
track, being impassable during the rainy season. A World Bank funded study
was undertaken to evaluate the technical and economic feasibility of upgrading
the road to an all weather route.
However because of the limited amount of traffic, the funds available for the
road improvement were severely restricted.
A detailed study of the hydrology of the area was undertaken, from which flow
discharges of all the natural drainage catchments were derived. This enabled an
evaluation of the hydraulic performance of the existing structures under flood
conditions.
Detailed inspections, measurements and surveys of the significant bridges were
undertaken in order to derive their actual load capacity. Least cost
modifications in order to bring the bridges to a uniform standard were developed
and costed. In parallel to this, alternative replacement designs (which
maximised use of local materials and labour) were also drawn up and costed for
economic evaluation.
On the basis of the economically available funds, a strategy of rehabilitation of
suitable structures along with replacement of severely deficient structures was
adopted. The work was undertaken in-country in collaboration with the
Ugandan consultants, Kagga and Partners to enable training and technology
transfer.
The existing bridges types included:
 Steel beam
 Reinforced Concrete Slab
 Timber
 Bailey
Typical modifications of the 6 existing bridges involved, re-kerbing,
reconstruction of parapets and resurfacing. A number of the steel beam
structures were converted to composite steel-concrete in order to
enhance their load rating.
Replacement structures were generally reinforced concrete box or beam
and slab, detailed simply to facilitate construction by local contractors.