Saleh Ahmed
Bangladesh Institute of Engineering and Technology | Dhaka

The core concept of the project is ‘Adaptive reuse of an infrastructure’. Site of the project is actually a 129 year old iron bridge (govt name: Bongo Sonahat bridge, Local name: Pateshwary bridge) located at Bhurangamari, Kurigram. The bridge will become abandoned in 5/6 years after the construction of new two Lane Bridge (700 m downstream from the old bridge). The bridge served the local community for many years. It is an asset for the community. After construction of the new bridge, how can we preserve and reuse the old bridge? How can we extend its longevity and adapt it to the new circumstances and make it useful again for the community?

The bridge has its own historical back ground. It was constructed in 1887 over Dudhkumar River. At that time it was known as Assam access Railway Bridge and had one lane. After the partition of 1947, the bridge was closed. In 1971, ‘MuktiBahini’ destroyed two central span of the bridge for preventing the Pakistani army to cross over the river. In 1984, some of bridge parts like girders, stringers was used to repair Tista Bridge as both the bridges have similar structural characteristics. In 1986, the bridge was repaired by the local Govt. The bridge came to attention of the media after reopening of Sonahat port in 2014 which is situated 10 km away from the bridge (the port was closed for 64 years). In 2015 a proposal was made by the Govt. to upgrade the port and construct a new two lane bridge for motorized vehicle for addressing the increase of traffic and trade in upcoming years.

The existing iron bridge consists of 9 span. Length of each span is 170 feet. Central 2 span and last 2 span are new and also the most vulnerable one (constructed in 1984/ type2/warren type truss). Older spans are pratt type truss. (Type 1). Total length 1530 feet.

The main idea is to work the bridge as bridge for community development. The bridge will bind together four aspects of the community such as river dynamics, unused/underused canal, and char area and fish production declination. Introduction of a new type of recirculating agriculture system may do the trick. The unused char area will be used to pumpkin and maize. The river will use for the development multi‐layer cage aqua‐culture (Fish production last for this area is 52.66 % because of various reasons). By product of the agriculture system can be used as co‐product of the aqua‐culture system or vice‐versa. As the river and char area working as an experimental lab, the bridge can be used as man power development center for accustoming local people with the recirculating agriculture system. The designed bridge can be divided into three level. The mid-level or ground level will act as an open public area. Various kinds of facilities are provided here for different kinds of public activities like outdoor board games (Carom, Lu‐du, and chess), food carts, shops, galleries, terraces. Institutional facilities like classrooms, workshops, focus discussion rooms, administrative facilities, teacher’s room, and accommodations for guest trainers are provided on lower level. Upper level houses basically pocket libraries, open terraces and seating areas. The bridge is flanked by four towers so that people can enjoy

panoramic view of the river at different heights.