Environment, Headlines, Latin America & the Caribbean

ENVIRONMENT: Fish Return but Problems Remain for Havana Bay

Dalia Acosta

HAVANA, Nov 20 1996 (IPS) - Recent strollers around the long-polluted waters of Havana Bay have been treated to a rare sight – fish are swimming in the Bay again, raising hopes that centries of contamination is at last being contained.

“I sometimes see a shad jumping, or other fish attacking the sardines, something I haven’t seen for a very long time,” says 70- yearold Pablo Olivares, who has lived near the port of Havana for the past 40 years.

Olivares said the waters are far cleaner than they were a few years ago, but even so, environmentalists are fearful that hundreds of years of human presence have taken an irreversible toll on the bay. While the upper levels of water show falling levels of hydrocarbon pollution, specialist reports stress that the real danger lies down on the sea bed.

Hundreds of thousands of cubic metres of organic sediment have settled on the bottom of the bay, substances which are far more poisonous than oil or its derivatives though far less visible, according to Granma International, the official Communist Party daily.

Havana Bay, is listed as one of the 10 most polluted ports in the world by the United Nations Development Programme (UNDP). It is viewed as a symbol of the damage humanity can wreak on the environment.

The 47 million cubic meteres of water in the bay cover a surface area of 5.2 sq km and directly affect the lives of 20,000 workers in the immediate area and thousands of people further inland.

Environmentalists and others are not hopeful of repairing the damage to the bay after the abuse it has suffered for hundreds of years, but they believe they can prevent the present situation becoming worse by forestalling new pollution.

“The fish may come back. But I don’t think the people of Havana are about to start swimming in the water like they did in the 18th century,” said Iramis Valdez, a 38 year-old historian who lives only a few metres from the opening of the bay.

Scientific interest in the deterioration of the bay dates back to 1886, but it was only in 1974 that the government identified the sources of contamination and produced specific measures for environmental improvements.

Officials at the Ministry of Science, Technology and Environment insist that water quality improved drastically between 1986 and 1994. Their figures show levels of oxygen dissolved in the surface was barely 0.6 milligrammes per litre of water in the years from 1986 to 1990, but tin 1994 this rose to 6.53 milligrammes per litre.

Meanwhile, the oxygen content in the deeper water of the bay increased from 2.42 to 4.96 milligrammes per litre and, at the same time the levels of hydrogen sulphate, hydrocarbons and fecal matter declined.

According to the specialists, oil spillages and the port operations are no longer responsible for the bulk of pollution in the bay. Studies carried out last decade measured the daily discharges of organic waste at 105 tons, coming from factories, rain water drains and the sewage network.

The bay also sops up the waste from a petrol refinery, several electricity plants, a gas terminal and an endless list of slaughterhouses, fishing operatives and distilleries.

According to Eduardo Normand Cabrera, an engineer, a environmental planning and management project to deal with the heavily contaminated bays and coastal areas has helped reduce the release of hydrocarbons and thereby the return of the marine species.

“The reduced spillage of hydrocarbons has diminished the vast oily patches which had blocked the entry of oxygen and, on oxidising, gave a nauseating appearance of putrefaction,” said Granma International.

The Ministry of Science reported the concentration of hydrocarbons went from 0.34 milligrammes per litre from 1986 to 1990 to 1.3 between 1991 and 1993, remaining at the “insignificant” figure of 0.3 milligrammes since 1994.

The causes of this reduction can be seen in the falling industrial activity registered in the island as a result of the economic crisis of the last six years.

But these knock-on effects from the crisis have also been aided by a series of government initiatives which have invested six million dollars in cleaning up the bay between 1986 to 1989.

The improvement of the bay has been given high priority by the authorities, who have banned the cleaning of vessels in the bay and recommended investment in waste water treatment plants.

The United Nations provided 400,000 dollars for feasibility and pre-investment studies, which are to be followed by contamination reduction projects.

“This bay needs massive work to put an end to contamination, and it will cost billions of dollars,” said an official from the National Commission for Environmental Protection. In the current economic crisis, it would be “impossible” for the nation to find the resources needed to finish the job, he added gloomily.

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