Trial Bridge Evolution in Nepal

Trial Bridge
Although Nepal was still closed to foreigners at the beginning of the 20th century, this did not deter the then government of Nepal to build trail bridges at important locations along a few carefully selected principal trade routes. These bridges were manufactured in Scotland, dispatched in “parcels” to Nepal and subsequently erected at the site.

As the pace of construction was slow and the number of bridges unsatisfactory, the Government established in 1964 the Suspension Bridge Division, which was superceded by the Trail Bridge Section in 2001. With Swiss technical assistance, a bridge type was developed that has proven to be durable and especially suitable for “long” spans. Typical bridge spans range from 120 to 350 meters. This “first generation” of trail bridges is denoted today as Long Span Trail Bridges.

In order to be able to respond to the demand for “important” bridges, studies were undertaken to identify major trade routes requiring trail bridges. This led to “Transport Infrastructural Maps” that have become in vogue not only for bridge builders but also for agents building roads or wishing to link roads into the trail network, as well as for trekkers.

Long span trail bridges were built mostly on the Main Trail at a rate of up to 30 per year. Although this was a significant improvement compared to the Scottish bridges, it was still not enough to meet the high demand for local bridges connecting the numerous settlements. Moreover, the sturdy long span bridges were too costly for poor communities.

Consequently, on the request of many communities, Helvetas developed another bridge type, modeled after traditional bridges that used to be built in the District of Baglung. The bridge type that emerged is based on reviving traditional skills, optimizing local materials and skills while minimizing the negative impact on the environment in order to ensure its replicability nation-wide. Communities reciprocated by submitting unprecedented requests initiating and undertaking the construction of local bridges. Spans for these Community-bridges range from some 40 to about 120 meters.

Trail Bridge Complected Project