An overview to help better understand the changes on our territory over the last 50 years

In 2012, RBL mandated an expert to carry out a prospective analysis of the evolution of the filtration capacity of the watershed, for the purpose of better understanding how the territory has changed over the last 50 years.  The use of the satellite technologies Landsat – 4 and Landsat – 7 place this project at the forefront of this type of assessment and will provide the leadership of RBL and concerned authorities a great deal of information about what resources to put in place.

 Some troubling data emerges from this study:

  1.  The watershed has lost 5% of its filtration capacity over the last 50 years, which represents some 850 ha;
  2. Agricultural activities have been increasingly left aside; large tracts of open fields have become forests again and other large spaces are now occupied by residences;
  3. The loss of swamps and marshes and especially the transformation of marshes into swamps (much less efficient for treating the quality of the water) has been a major factor: increasing the water level in the lake, several work projects of containment, filling-in wetlands;
  4. The number of ponds and small lakes owned privately has soared astoundingly;
  5. The urbanization process has been accentuated and has also removed many natural water filtration spaces.

 The report covers all these phenomenons and proposes ways to restore the filtration capacity with measures which are easy to implement, notably in terms of a major restoration and drainage ditch restoration program.  

 The site which have been given priority include: Fisher Bay, the bottom of  Conference Hill, Douglass Beach, the Beach Hill sector and the Robinson Bay, Domaine Brome and Rock Island Bay sectors. To be continued.

Evolution de la capacite filtrante du bv du lac Brome