THE RECENT rainfall caused flooding in some parts of the country, but the water has been leaving the reservoirs almost straight away, with only slight increases in water volume being registered in some dams. According to the Instituto da Água (INAG), only if it rained without interruption until the end of the year would the country overcome the drought situation.
“In the south, reservoirs continue to remain almost empty, with average capacities being lower than 20 per cent,” explained Rui Rodrigues of INAG. The Arade reservoir is almost dry, with its capacity at below five per cent, and the Alqueva reservoir, due to energy production, in fact saw a reduction of one centimetre.
Meanwhile, in central Portugal, the water level of the Cabril reservoir increased by six centimetres over the last few days, as did that of Castelo de Bode. “Six centimetres is nothing, taking into account the capacity of these reservoirs,” underlined Rodrigues, emphasising that these two dams currently stand at around 60 per cent of their usual capacity.
In the north, the situation is a little better. Generally, reservoirs are currently at around 40 to 50 per cent of their average capacity. In the Douro, for example, the water volume at the Torrão reservoir has increased by 20 centimetres, thanks to the rain of the last few days, “a value of little significance in percentage terms”, explained Rodrigues.
Of primary importance is the necessity to combat the deficiency of moisture in the soil, which has to reach saturation point to allow drainage to streams and rivers, water that will then flow towards the reservoirs.
Actually, the water deficit in Portugal has reached 500 millimetres due to the fact that, between October 2004 and September 2005, there was only 398 millimetres of rainfall, against an average of 912. In September, only 14 millimetres of rain fell, when the normal amount is 41.
According to Rui Rodrigues, to overcome the drought situation, Portugal needs between 200 and 300 millimetres of rainfall, a sufficient amount to allow the saturation of the soil and flow of water to the reservoirs.
The most recent fortnightly report from the Comissão Para a Seca (drought commission), stated that 61 per cent of the country is presently facing a situation of extreme drought, while 36 per cent is in a condition considered as severe.