Germany's Federal Office of Statistics in Wiesbaden released figures on Friday, showing that last year's flood waters from the river Elb and its subsidiary rivers doubled the amount of pollution in rivers, streams and lakes in the area. On the basis of an inquiry published by the statistics office, the flood waters carried some 4,800 cubic meters of fuel oil and other dangerous substances into the environment. In most instances, the pollutants were washed out of private fuel oil tanks in the affected areas. Over the past few years an average of 6,400 cubic metres of pollutants have made it into German waters. Whilst half of that figure can usually be extracted, the Statistics Office said that 70 percent of last year's volume would stay in the system permanently as it could be neither recycled nor eliminated.