I received your article “Manitoba cattle producers steamed” (WP, May 26) from a family member, and would like to compliment your staff on having done their own calculations on the effect of the diversion.
I have family with property by the lake and so, concerned, I did similar calculations.
In my calculations, I have assumed an average of 25,000 cubic feet per second coming in from the diversion from the middle of April to the middle of June, based on a number of 23,000 cfs I obtained from an online government release on April 17… I realize 25,000 is an approximation as I do not have daily data points, but it’s not unreasonable.
Assuming that the inflow from the Waterhen and Whitemud rivers is approximately equal to the outflow … they cancel each other out. Thus, aside from precipitation and evaporation (which should be roughly equal), the only additional factor is the diversion input.
Over two months at 25,000 cfs, I calculated a net rise of 2.56 feet from the diversion (using an area of 4,700 square kilometres for Lake Manitoba)….
Also, it’s clear from the Manitoba government website that water levels were near normal up to the middle of April when diversion levels increased dramatically.
Yes, the Waterhen and Whitemud increased at this time as well, but again, they were a relatively small fraction of flow compared to the diversion.
I find three points absolutely incredulous:
a) (Emergency measures minister) Steve Ashton states that the flood is natural -was he referring to Lake Manitoba flooding (which clearly is not natural), or the amount of water in the province altogether (which is natural), I wonder?
b) That Manitoba Water Stewardship has not yet approximated a calculation of the effect of the diversion….How did the government manage to figure out that lev-e ls on the lake would be lower without the diversion and the Fairford dam, and yet calculations of the input from the diversion have not been done?…
c) That the University of Manitoba head of graduate studies (and civil engineer) Jay Doering does not think that the diversion is causing the rise in lake levels, but instead is from natural runoff (when the numbers clearly show that the diversion is putting far more water into the lake than the natural sources). Is he aware of the numbers?…
Cattle producers around the lake are steamed, but there are many others too. Again, I am shocked at these seemingly obviously incorrect statements from several expert sources, and would like to know what information they were basing their statements upon….
Andrew Zubrycki,Winnipeg, Man.