MADRID (Reuters) - Water levels in Spain's hydroelectric reservoirs dropped to under half capacity in the week to Monday night, official data showed, as Spain's dry autumn continued to worry power companies and farmers.
Hydroelectric reservoir levels fell to 49.4 percent from 50.3 percent of capacity a week earlier. As little as four months ago, Spain's hydro reservoirs were more than 80 percent full.
In contrast to normally-rising levels in the autumn, Spain's hydro-reserves have fallen consistently this season and volumes are now nearing multi-year lows hit in 2005/06.
However there was better news from Tuesday as heavy rains fell across much of Andalucia and Galicia and as wide-spread showers forecast for at least the next three days.
Tuesday's level compares to 69.5 percent in the same week in 2006 and a 10-year average of 63.8 percent for the 47th week of the year, the Environment Ministry said.
That means there are 7,594 gigawatt hours (GWh) of electricity available, 184 less than the previous week, and 73.9 percent of capacity available a year ago.
In the last week, power companies have generated 317.9 GWh of hydroelectric power, taking the total so far this year to 24,392 GWh, which is still 27.8 percent more than in the same period last year.
In a good year, some 12 percent of Spain's electricity comes from hydropower, but in dry years like 2005 and 2006, this falls to about 8 percent.
Spain's biggest utility, Iberdrola produced 22.6 percent of its power in Spain from hydro-electricity in the first nine months of the year -- more than any other source.
Drinking water reservoir levels slipped to 38.0 percent from 38.2 percent last week, 39.6 percent in the same week last year and an average 48.3 percent in week 47 over the last 10 years.
(Reporting by Ben Harding; Editing by Chris Johnson)