Absence of a proper sewerage system, the practice of blacktopping the roads and paving the base of the drains are some of the major factors contributing to the growing problem of urban flood in Assam, stated noted drainage and sanitation expert Dr Binoy Kumar Das while talking to this correspondent.
Dr Das, one of the architects of the 1971 Drainage Master Plan of Guwahati, said that in the developed countries, sewerage system is a must. In those countries, drains are meant for carrying only the stormwaters. In the dry season, the drains remain dry.
Moreover, drains are made in these countries according to the slope of the land. Artificial wetlands are provided to the gardens with man-made topographies so as to retain most of the stormwaters in the areas within the gardens. Besides, by preventing rainwaters from spilling onto the roads, this helps also in keeping the groundwater tables of the gardens up, thus keeping their greenery booming.
In those countries, rainwaters are retained wherever possible, unlike in our country where the waters are released into roadside drains. We need to retain rainwaters within our individual campuses and for that purpose we need to create recharging points for the groundwater tables by digging ring wells or installing some low-cost devices within our individual campuses.
In Assam, we lack sewerage system in almost all areas, barring some of the industrial townships. This is adding to our urban flash flood problem.
Here, paving the bases of the drains is also a popular practice. But, not paving the bases of the drains is important. It helps in keeping the problem of flash flood under control. Paving of the drain bases is adding to the flash flood problem by blocking the percolation points for the storm waters.
To get rid of the urban flash flood problem, we should also give up the practice of blacktopping or paving the roads and avenues and should preserve open spaces and wetlands, said Dr Das.