Britain's soggy reputation has been turned on its ear as it weathers one of its worst droughts in history.

The evidence of the prolonged dry spell is everywhere: riverbeds have dried up and streams have been reduced to a trickle. One water reservoir near London contains half the water it should.

Britain has seen dry spells in the past. But the drought is one of the worst to occur in nearly a century.

Last year, the drought cost farmers about 25 per cent of their crops and this year it could be worse. There are fears the water crisis could have implications for wildlife, tourism and industry.

"For the whole year, 2011, it's the driest year we've had since 1921," environment specialist John Orr told CTV News. "And for the past five months, it's the driest we've ever seen."

Experts say Britain badly needs a prolonged downpour. If the skies don't open soon, water rationing could be next.

Densely populated London may be one of the first areas to be ordered to shut off the taps.

"Unless we have significant rainfall over the next couple of months, we are going to be facing very dry conditions with an impact on farming again, and on horticulture, but also quite probably the public water supply," said Britain's Environment Minister Caroline Spelman.

This isn't the first drought to hit England. In the early 1970s, a prolonged dry spell shut off the water mains and forced people to collect water from central distribution points.

But this is worse, so bad that a few rainy spring days won't solve the problem. The country needs a prolonged downpour, and very soon.

With a report from CTV's London Bureau Chief Tom Kennedy