MONTREAL — Shippers and port operators say rising water levels in the St. Lawrence Seaway could cost the economy more than $1 billion.
A new study from the Chamber of Marine Commerce warns that opening the floodgates further at a dam in Cornwall, Ont., would wash away between $1 billion and $1.75 billion in revenue for businesses on both sides of the border.
A board of control recently increased the flow at the Moses Saunders Dam to allow more than 10,400 cubic metres of water per second out of Lake Ontario, an exceptionally high rate that follows heavy spring snow melt and rains and record water levels on several Great Lakes.
The rapid outflow interrupts navigation on the St. Lawrence Seaway. Bruce Burrows, president of the Chamber of Marine Commerce, estimates it costs businesses up to $4 million for every day it’s in place.
Burrows approves of the increased outflow — which the board opted to maintain on Friday — due to flood problems for homeowners upstream, but says a study into water levels and their causes is needed along with a resiliency plan.
Lake Ontario rose to nearly 90 centimetres above average this spring, reaching a record 75.92 metres above sea level before stabilizing recently. Lakes Erie and Superior also hit record heights.
The Canadian Press