Ontario Waterways Directors Office
P.O. Box 567, 2155 Ashburnham Drive
Peterborough Ontario K9J 6Z6
July 14, 2016
Thank you for your May 31, 2016 correspondence regarding spring water levels in Pigeon Lake.
The high water levels on Pigeon Lake in 2016 were due to a significant weather event which was evident across a large region. Rain on snow events drive the larger floods on the Trent River System as was the case in 2016. During the month of March there was 170.5 mm of precipitation, 127-3 mm of rain which was recorded at the Haliburton 3 Climate Station. The climate normal (i.e. 30 year average) for that same station is 75-4 mm of precipitation and 37-4 mm of rain. In general, there was more than as much precipitation than average and over three times as much rain. The March 2016 precipitation and rainfall exceeded the highest historic monthly values reported at the Haliburton 3 and Minden Climate Stations.
Precipitation gauges operated by the Trent Severn Waterway in the northern section of the watershed showed an average of approximately 100 mm of precipitation from March 26 to April 1.
The spring freshet for 2015 was very different as very little rain fell during the snow melt period. Further, there was a significant amount of snow erosion. In 2016 while the amount of snow was less than average however, the significant amount of rainfall resulted in large quantities of runoff.
There are no flood control reservoirs on the Trent Severn Waterway. The reservoir lakes are intended to be drawn from to aid in navigation during the summer. These lakes fill very quickly during extreme weather events and provide little in the way of flood mitigation.
High flows and water levels were observed everywhere on the Trent River and Severn River systems during this year’s spring freshet. Flood Warnings or Flood Watches were issued by the Ontario Ministry of Natural Resources and Forestry branch in Bancroft, Kawartha
Conservation, Lake Simcoe Region Conservation Authority, Lower Trent Conservation and Otonabee Regional Conservation Authority. The Trent-Severn Waterway re-posted information released by the partners as well as providing water management updates on its website to support dissemination of this information.
Throughout this extreme weather event, Parks Canada supported communication of water level activity amongst its partnering organizations and to the public. Parks Canada staff participated in conference calls hosted by Ontario Ministry of Natural Resources and Forestry, Bancroft, before and during the high water event. During the highest water levels of the 2016 spring freshet, these meetings were held daily, including weekends. Many municipalities, the OPP, Fire Marshall and Conservation Authorities were in attendance at these meetings, and Parks Canada staff provided insight on observed inflows, current outflows, changing conditions and operations.