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In 2004, nitrate levels in two-thirds of the Water Services Corporation’s boreholes exceeded levels laid down in the European Union’s Nitrate Directive
James Debono
Farmers and the Environment and Rural Affairs Ministry are at loggerheads over the quality of water from the new sewage treatment plant at ic-Cumnija, in Cirkewwa.
In January, during the presentation of the state of the environment report, Minister George Pullicino promised farmers would be supplied with treated water before launching a crackdown on illegal boreholes which were draining Malta’s underground water sources.
Three weeks after, the ministry acknowledged the treated water’s salinity was expected to be high, and would limit its potential for reuse by industry and agriculture.
Farmers claim the water is too saline to be used for irrigation. But the ministry claims treated water from ic-Cumnija will not damage crops, even if the water will be as salty as that supplied from the Sant Antnin waste recycling plant. The ministry claims Sant Antnin’s treate waster did not have “any significant negative effects”.
Peter Axisa, the president of the Association of Farmers, disagrees. “If the intention is to irrigate fruits and vegetables and not some new breed of genetically modified grass, then we all know what poor quality crops Sant Antnin water is producing.”
Axisa says water from the Sant Antnin plant is unsuitable for sustainable irrigation because it lacks final treatment.
The government is considering final treatment, saying the quality of treated wastewater can be improved by “polishing” it with normal, reverse osmosis water.
Polished waste water increases its reuse potential, but also comes at a cost. In December, Minister Austin Gatt said it would cost as much as 70c per cubic metre to treat sewage water for reuse by farmers. Disposing of it into the sea instantly would only cost 17c.
Although tariff structures have not yet been established, setting up such a price for waste water could discourage farmers from using it.
The ic-Cumnija plant in the north of Malta is expected to produce an enormous quantity of 6,500 cubic metres of water a day.
The new supply will alleviate pressure on groundwater sources used in agriculture and industry.
According to the state of the environment report by the Malta Environment and Planning Authority, the extraction of water from boreholes is estimated at 30 per cent of total water production.
In 2004, nitrate levels in two-thirds of the Water Services Corporation’s boreholes exceeded levels laid down in the European Union’s Nitrate Directive. Chloride levels in the mean sea level aquifer system also exceeded the World Health Organisation’s quality standards.
The report however states that recycled water from treatment plants is of poor standard due to its salinity, originating from the infiltration of sea water into the sewerage system, and the dumping of brine from desalination and toilet flushing.
However, only 29 per cent of recycled water can be expected to be use, even if it is offered free of charge, because major agricultural areas like Burmarrad are far away and out of reach of the plant.
The environment ministry plans to pump the water into reservoirs where it will be stored on high ground, in places like Mizieb and Wardija. It will then be distributed to the low-lying areas of Pwales, Qammiegh, Cirkewwa and Burmarrad.
The water could also be used in an afforestation project in a nearby area.
The ministry however said the 29 per cent figure reflects the present demand for unpolished water, expecting a higher demand if the water is further treated.
jdebono@mediatoday.com.mt
Links:
www.maltatoday.com.mt/2005/11/06/t15.html
www.maltatoday.com.mt/2005/12/25/t9.html
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