Ajit Patowary GUWAHATI, July 31 – Underground drains laid in many city areas are also accentuating the city’s flash flood problem. The underground drains laid without any proper study of the silt-load carried by the storm run-off from the city hills, are now rendering no service to the city people in providing relief from the rain-induced flash flood problem, said water resources engineers here who have been keenly observing the flash flood-related situation of the city.
The inundated main road of the Pub Sarania area of the city, which is built over an underground drain. – AT photo
Lack of the actual rainfall data is also a major hurdle in preparing the drainage plans of the city to match its rainfall. The rainfall data used in designing the city’s drainage plans virtually belong to the Borjhar area. The rainfall pattern of Borjhar area is not similar to those of Panbazar, Chandmari, Dispur, Khanapara etc areas of the city.
The Pub-Sarania Main Road is built over an underground drain. But the authorities, which built the road, have covered the manholes of the drain with thick layers of bitumen while doing the carpeting.
The Lachit Nagar Main Road is also built over an underground drain. And the authorities have covered the manholes on this road too with a thick layer of bitumen.
Covering the manholes with bitumen has resulted in great problems in opening these holes to remove the silt from these drains. It is natural that as these drains have never been cleaned since their construction, they are naturally filled with silt. It is feared that manually these loads of silt cannot be removed, because, the pressure of stormwater for several years on them has transformed them into huge compressed pieces.
It is feared that the interiors of the culverts constructed in Chandmari area, across the GNB Road, running in a south to north direction, are also suffering from the same condition. Due to lack of any cleaning activity for the past several years, these culverts have become clogged, said the engineers.
The covered drains have many problems in a city like Guwahati. The planners of these drains simply overlooked them, said the water resources engineers.