Le niveau du lac Ontario est le plus bas jamais vu depuis 10 ans: le peu de neige et de pluie font que le niveau est 47 cm de plus bas que l'an passé. De plus, les sédiments charriés par le ruissellement qui aboutit dans les cours d'eau s'accumulent au fond de l'eau et empirent la problématique.
Les amateurs de voile aimerait bien qu'on drague le fond pour pouvoir sortir leur embarcation ce printemps, mais ces travaux nécessitent un permis de Pêche et Océans qui l'accordent rarement durant la période de fraie.
Comme si tout çà n'était pas suffisant, il faut se rappeler que moins d'eau pour diluer les polluants veut dire que les plans d'eau peinent à supporter des écosystèmes en santé, mettant à risque les sources d'eau potable des municipalités.
Ici au Québec, il semblerait que ce soit le Lac Saint-Jean qui souffre d'un manque de précipitations. Rio Tinto Alcan contrôle le niveau d'eau de ce lac avec son barrage et achète déjà de l'électricité d'Hydro-Québec afin de ménager l'eau qui s'échappe de son barrage. Source: http://www.radio-canada.ca/regions/saguenay-lac/2010/04/27/004-niveau_lac-st-jean.shtml
Par contre, il semblerait que les rivières du coin pourraient se renflouer, du moins localement. Un avis le 5 mai: " Les fortes précipitations des derniers jours au Saguenay et plus particulièrement dans la Réserve faunique des Laurentides, provoqueront un fort débit d’eau dans la Rivière-aux-Sables au cours des prochaines heures." Source: http://www.lbr.ca/article-5-13740.html
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"Low water keeps boats in dock
Water levels in Lake Ontario are the lowest they've been in at least a decade, with a snow-light winter and dry spring dropping levels by 47 centimetres compared with April, 2009.
At the same time, high silt levels swept in from the St. Lawrence are clogging up harbour waterways. The dramatically dipping water line isn't record-setting, and is nowhere near the lake's lowest recorded level in 1935. But it's pitting the lake's divergent users against each other in efforts to mitigate the effectsThe levels, say observers on both sides of the border, aren't due to any cataclysmic change in water flow. All the Great Lakes are seeing low water levels this year, largely due to a lack of precipitation. But it's adding urgency to calls for better protection of the region's fresh water.
“What the repercussions on the whole lakes are I don't think anyone really knows right now,” says University of Toronto ecology professor Hélène Cyr. On a basic level, she says, it means previously shallow areas are dry and deep areas are shallow, which disturbs fish habitat. Mark Mattson, president of advocacy group Lake Ontario Waterkeeper, says less water means less lake, and a higher concentration of toxins.
“If the Great Lakes don't maintain their natural water levels, you're going to see destruction of wetlands and fish habitat, bird habitat. … If it's not able to clean itself and be able to support a healthy ecosystem, then the communities that rely on it are going to have a degraded water supply.”
This weekend, about 600 sailboats were scheduled to launch at Bluffer's Park to mark the start of boating season. But about two-thirds of them, including Mr. Switzer's 33-foot sailboat Elusive, won't be able to make it out of the harbour."
Excerpts from article written by Anna Mehler Paperny from the Globe and Mail here: http://www.theglobeandmail.com/news/national/toronto/low-water-keeps-boats-in-dock/article1542776/
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