Georgetown’s Flash Floods Now More of A Human Problem

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By Chaitram Aklu – FRGS

Late last June and early July, when heavy rainfall produced flash floods that submerged several streets and lots in Guyana’s capital Georgetown, making streets indistinguishable from the drainage canals, the mayor lamented that City Hall was not only to be blamed for the flooding.

The drainage infrastructure of Georgetown which forms part of the 646 mile Guyana coastal plain lies below sea level at high tide, and is still very much based on the old gravitational drainage system which over the decades have been complimented with the addition of high capacity electrical pumps.

The mayor stated that the drainage system was clogged by items such as furniture that were thrown into it. “Many of the areas were clogged with plastic bottles, plastic bags, old cloths and even chair (sofa sets)”, he was quoted as saying by the media. A common practice in the city is selling fresh fruit juices in plastic bags, which once the contents are consumed, are discarded on the street. The city Council imposed a $200 (Gy) residential charge per barrel last year which could lead to an increase in illegal dumping.

A Ministry of Communities solid waste management strategy document for 2017-2030 states “Littering and illegal dumping are widespread; there is limited emphasis on waste reduction and resource recovery.” And “littering and illegal dumping in drains, rivers, parapets, and vacant lots are widespread.” Yet the city has a 123 acre-landfill located just south of the city for its waste disposal. Opened in 2011 it receives over 120 000 tons of waste each year and expects to reach capacity in 2036.

But past experiences explain the potential and actual dangers faced by Georgetown and the entire Atlantic coastal region, during high –intensity short duration rainfall that occurs mainly during the two rainy seasons – November-February and May-July. In fact it was because of flooding that the capital was moved from an island in the Demerara River to its present site at the mouth of the river.

Basically there is a two-fold problem arising from its geographic location. The city has to be protected from the Atlantic Ocean because it is below mean sea level at high tide. High tides are usually 10.5 ft. or higher and exceptional high tides are even higher. At the same time runoff from heavy rainfall has to be drained to prevent flooding.

To a greater extent the gravitational drainage method has become inefficient due to increased human development – increased runoff due to construction of roads, concrete drains, housing, car parks and pavements. Urbanization of the city increased rapidly. In 1950 the area of the city was 2.5 miles and the population was 75, 000; 1969 it was 90, 000; in 1970 the area was extended to 15 sq. miles and by 1980 the population was 200, 000. As of July 2019 the estimated population reached 235, 000. (The estimated total population for the country is 782,984 according to UN World Population Prospects data.) Correspondingly the built up areas increased by over 50 percent and is intensifying. With the increasing population the city’s capacity to remove thousands of tons of solid domestic wastes, construction and industrial wastes has been a growing challenge both administratively and economically.

In January 2018, after two of the seven waste collection companies halted their services over non- payment, City Hall responded by issuing termination letters to the companies. The widely respected Stabroek News in an editorial stated, “ — no one is surprised that it is now as clear as day that the city lacks both the inventory and the managerial capacity to manage urban garbage disposal and that the task of so doing belongs, at least for the foreseeable future, with the private sector.”

In 1978, this writer warned in the national press of the urgent need to protect the environment in city. The warning was prompted when in an effort to expedite the clearing of the drainage canals heavy excavation machinery was used to desilt them. It proved to be environmentally destructive especially because operators were not trained to excavate leaving a gentle slope on the parapets. The result was widespread bank and soil slumping and collapse of several roads into the canals. Since then street levels have sunk resulting in the reduced containment capacity of the canals even before the onset of the heavy rains.

In 1994 the engineering firm Halcrow Ltd. reported in a study that confirmed the result. “Increased demand has taken place during a period of declining capacity due to the reclamation of drainage, a reduction in the maintenance of existing infrastructure, the informal use of drains for refuse disposal and the inefficiency of a gravity drainage system which can only operate at low tide,” the study noted.

Not much has changed as the 2017-2030 waste management strategy noted, “Littering and illegal dumping —– are widespread and have negative impacts on public health and the environment including blocking drains and kokers (sluices) which contribute to flooding.”

The entire coastal region is vulnerable to the combined effect of exceptional spring tides, and strong onshore winds which make the ocean rough and dangerous and may cause overtopping of the existing sea and river defenses. During these times also the rivers which empty into the ocean become tidal for up to 60 miles upstream. As a result the system can only operate a few hours a day when the tide is out – not long enough to release the quick buildup of runoff from heavy rainfall. Astronomical data shows that exceptional high tides can be 20 percent or higher than normal tides and generate waves averaging 10.5 ft. At crucial times the pumps may not function.

The dangers of flooding in Georgetown have always existed and there has been a constant battle to mitigate the effects especially during the rainy seasons. With more data now that there is increased global warming and the threat of rise in sea level, there would be increased flooding from rain storm and river surges and exceptional high tides. The dangers are already compounded by decreased municipal drainage capacity.

The International Panel on Climate Change (IPCC) estimated that to protect its low coast, Guyana would need to budget 2.12 percent of its annual GNP to erect shore protection structures. Costly as it would be, the country would need to increase the efficiency of the drainage system since there are no known plans to move to higher elevations.

The mayor’s statement is valid. But City Hall was given a mandate and must show that it is capable of carrying out the mandate to provide services for all. It must lead the way in maintaining the efficiency of the fragile drainage system, waste collection and disposal, among its other municipal administrative responsibilities – including strict enforcement of littering and dumping regulations. For now, the city could embark on an effective environmental education program with a strong focus on maintaining a clean and healthy city through waste reduction, recycling and civic responsibility with the understanding that sustainable development is development that meets the needs of the present without compromising the ability of future generations to meet their own needs.

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