Some of the UK's most environmentally sensitive lakes and streams are recovering from the effects of acid rain.

The amount of acidic sulphur In UK waters has generally halved in the last 15 years, according to new research from the University College, London (UCL). Because of this, acidity in the water is declining and wildlife is starting to recover.

The UCL research reports on 22 of the most sensitive waters in the UK, which have been monitored continuously since 1988. In about half of the sites, native algae and invertebrates are showing signs of recovery.

In others, acid-sensitive mosses and other aquatic plants have been found for the first time in fifteen years. And at three of the most acidic sites identified juvenile brown trout have recently been found for the first time since monitoring began. It is thought that plants fish and insects are starting to return to these waters thanks to the emissions controls brought in by Government, as well as greater use of natural gas rather than coal.

Since 1970 there has been an 84 percent decline in in sulphur dioxide emissions and a 37 percent decline in emissions of nitrogen oxides. These gases, along with emissions of ammonia from agriculture are largely to blame for acid rain. Fisheries and Local Environment Quality Minister Ben Bradshaw welcomed the research, but stressed that more still needs to be done. He said: “It will take time for these sensitive waters to recover from the devastating effects of acid rain. So, it is extremely encouraging that today's research suggests that they are starting to recover.

“The research shows that the measures we have put into place to control emissions of sulphur dioxide and nitrogen oxides are starting to pay off. The switch from coal to gas in both power generation and in the home, while being mainly for economic reasons, has also meant a lot less pollution. New, strengthened measures – such as the implementation of the Large Combustion Plant Directive – will help ease the situation even further.

“Unfortunately, today's research does not mean our waters are in the clear. It will take time for these sensitive waters to recover and, as the impacts of sulphur decrease, the impacts of nitrogen pollution from emissions become more noticeable. “This is an issue without boundaries, so our focus must be on working closely with our European and international partners.”