Closing the floodgates

Colombo and many other parts of the country have been experiencing incessant rain for the past few days. Several areas of Colombo have experienced flash floods as a result, severely inconveniencing residents, motorists and pedestrians. This is not a one-off event.

Flash floods occur in many parts of the country whenever it rains heavily for a couple of hours. This has been happening year in, year out without any solution in sight. Apart from floods, heavy rains usually result in landslides in some parts of the country.

The lack of planning seems to be the primary cause for this state of affairs. City planners in most instances have not accounted for the impact of heavy rains. One can see plenty of new and newly repaired roads with no drains on either side. All new roads must necessarily have drains to accommodate excess rainwater.

There are many other factors that contribute to floods and landslides. The non-disposal of garbage and the consequent blockage of drains and manholes are major problems. The blame lies squarely on local bodies that do not discharge their responsibilities in this regard. They should engage in proper garbage disposal methods which will not only prevent floods but also pre-empt the spread of diseases. The public too have a role to play in garbage management. For example, it is not too difficult clear and clean drains that originate in or run past one's own house.

The reclamation of water retention (marshy) areas and the construction of unauthorized structures in such areas is another major problem that leads to floods, as excess rainwater has nowhere to flow to. Some local bodies seem to be powerless to stop this damaging trend. Tough laws should be brought in to stop the reclamation of water retention areas, if the present laws are inadequate to deal with it. Rainwater retention areas should be clearly demarcated and publicised widely so that no development can take place in such areas.

In the meantime, an urgent remedy must be found for the recurring problem of floods, which have claimed several lives over the last few years. It was just last year that a women fell into an uncovered, water-filled drain amid heavy rain in Colombo and died, although passers by tried to rescue her. There have been many similar incidents elsewhere in the country.

The municipal and urban councils should formulate viable solutions in tandem with the provincial council in their respective areas and the Central Government. The help of planning engineers and foreign experts should be sought if needed to resolve this vexed issue.

This brings us to the question of rainwater harvesting. We have never had a serious policy in this regard whereas many other countries do have strategies to make use of rainwater that would otherwise go waste. It will be a fillip for agriculture and various other commercial purposes. Rainwater harvesting is not an expensive process" even ordinary households can do it.

According to scientific terminology, rainwater harvesting is the gathering, or accumulating and storing, of rainwater. Rainwater harvesting can be used to provide drinking water, water for livestock, water for irrigation or to refill aquifers in a process called ground water recharge. Rainwater storage systems are simple to construct from inexpensive local materials, and are successful in habitable locations. Roof rainwater is usually of good quality and in some cases, does not even require treatment before consumption (unless the area is heavily polluted). Household rainfall catchment systems are appropriate in areas with an average rainfall greater than 200mm per year, and no other accessible water sources (Skinner and Cotton, 1992).

The same authors mention that there are a number of types of systems to harvest rainwater ranging from very simple to the complex industrial systems. Generally, rainwater is either harvested from the ground or from a roof. The rate at which water can be collected from either system is dependent on the plan area of the system, its efficiency, and the intensity of rainfall. Sri Lanka gets plenty of rain each year and some areas get more rain than others. Thus rainwater harvesting could be a potential lifesaver and a cost cutting measure in many areas. The authorities should explore the possibility of establishing rainwater harvesting systems throughout the country, especially in the Wet Zone. It can perhaps lead to the prevention of floods as well.

The problem of landslides should also be addressed in a more coherent manner. The authorities declare certain areas as out of bounds whenever there is a danger of a landslide or earth slip. However, residents and shopkeepers move in as soon as the danger signal is taken off. This is not a very satisfactory situation. The National Building Research Organisation and the Geological Survey and Mines Bureau should together undertake a comprehensive study on landslide-prone areas in the country. If certain areas are deemed permanently unsuitable for human habitation, they should be declared so. No constructions should be allowed in such areas. Moreover, one cannot rule out the possibility of an earthquake hitting Sri Lanka. There have been several earth tremors and quakes close to Sri Lanka in recent years.

While there is still no reliable prediction method(s) for earthquakes, apart from early warning mechanism for tsunamis, one can predict weather patterns with a fair degree of accuracy thanks to an extensive network of weather and geo-sensing satellites. There are many Websites which give a highly accurate picture of Sri Lanka's weather (or for that matter, for any other country/region in the world) for five or six days ahead. I have several applications on my iPod Touch which do the same. Unfortunately, most people do not have access to such information and they have to rely on the broadcast and print media for weather information.

Alas, there is a void here. Weather bulletins and satellite maps have disappeared from most news bulletins, replaced with just a word or two from a duty forecaster at the Met Department. Glance through any foreign newspaper or watch any foreign newscast, and one can see an exhaustive presentation on rainfall and other weather patterns. That is not happening here. The Met Department should improve its forecasting capabilities further and the media, both print and electronic, must support the Department to get the message across. That will give people countrywide a picture of the current and future weather patterns at little or no cost to them. It will also enable them to take action to face any adverse weather " it can be a simple decision such as whether an umbrella should be taken or not when stepping outside the house. The authorities should also formulate a flood prevention and weather policy that encompasses a whole gamut of weather-related issues with input from the public, municipal authorities, Pradeshiya Sabhas and civic organisations. That could be part of a long-term approach to literally stem the floods.