Acid precipitation has killed the fish populations of 14 rivers in Nova Scotia's southern upland region.
Twenty rivers have only 10% of their Atlantic salmon left, and another thirty are threatened.
SEE ACID RAIN MAP OF NOVA SCOTIA
It also impacts the Pleasant and Dennys Rivers in Downeast Maine.
West River - Sheet Harbour, Nova Scotia
Six years ago an automated liming program was put in place on a river east of Halifax, and by 2010 the number of Atlantic salmon parr, of trout and of invertebrates had come back tremendously.
In 2011 there is great excitement - in the first week of the smoltwheel operating, 1875 smolts were captured, measured and released.
Acid precipitation is produced from sulphur dioxide and nitrogen dioxide emitted from burning fossil fuels. Coal and oil-fired boiler and ore smelters emit sulphur dioxide. Motor vehicles emit nitrogen oxide. These gases combine with water in the atmosphere to form nitric and sulphuric acids, and are dispersed by winds before falling back to earth in the form of rain, dew, snow, sleet and fog, harming plant and animal life. The major sources of acid precipitation are in the Ohio Valley, U.S. Mid-Atlantic states, and southern Ontario, carried by prevailing winds to the northeast.
ASF and the Nova Scotia Salmon Association (NSSA) have been pioneers in addressing the matter of acid rain mitigation in Canada.
The impacts of acid rain are far-reaching:
- There is a state-of-the-art computerized liming doser on the West River Sheet Harbour. Download backgrounder
- By late 2009 it was clear that the the limedoser was increasing the productivity of the river, bringing conditions back towards a normal pH. The river continues to be monitored.
- ASF and NSSA sponsored a major acid rain mitigation conference in 2007. Proceedings can be downloaded (4mb .pdf) Click here
- Acid rain affects the health of rivers, lakes, fish, forests and people.
- Nova Scotia is hit with more than twice the acid rain that it can safely handle.
- In Canada, Nova Scotia suffers the most from loss of and damage to fish habitat.
- Like the canary in the coal mine, the wild Atlantic salmon is a biological indicator that signals loss in water quality.
- Nova Scotia has lost one-third of its salmon production on the Atlantic coast.