The perennial problem of water logging
People in the capital were waiting for the rains eagerly. And when it did come on Wednesday it did not just rain it poured. And the showers brought life in many places of the capital to a standstill. While people waded through knee-deep water, public transport refused to ply in various parts of the city. Commuters were stuck for a long time in the morning rush hour traffic across the city and some of them took to social media to post pictures of water-logged and clogged roads. They also wrote about the irony of dark clouds providing succour from the unrelenting muggy weather and yet adding to the woes of Dhakaiites.
Water logging after moderate to heavy rainfall is a perennial problem in Dhaka. Every year rains make some parts of the city to suffer from water logging. The rainwater infrastructure, if it exists at all, is not sufficient to guarantee the drainage of the water so that streets in low-lying areas get inundated. Roads are blocked leading to traffic jams, pedestrians have suffer immensely and especially the urban poor, living in slums or squatters have their homes often damaged by the water, which may take several days to recede.
But water logging happens everywhere, whether in rich or in poor neighbourhoods. The water becomes polluted when it mixes with the garbage and waste that is littered everywhere and apart from disrupting traffic it also becomes a risk to health.
The citys lake and canal system, which acted as an effective drainage system, is in disrepair. Many wastewater conduits out of the city such as storm-water drains, sewers and canals are silted. Besides, gully pits are blocked and there is a time lag for water to reach the pumping stations. This leads to flooding on the surface. Poor solid waste management is a major culprit.
The original design of the citys drainage system was based on the drainage capacity of the sub-basins. But the unplanned diversion of surface runoff from one sub-basin to another is one of the reasons for overloading of the existing drains resulting in flash floods. The filling up of ponds and marshlands to obtain real estate is linked to increased problems of drainage and flooding.
One way to tackle the water logging problem as well as the ever decreasing levels of ground water could be rain water harvesting, a technology that has been used in these parts of the world for hundreds of years but which fell into oblivion during the colonial rule.
