St. Lawrence Seaway operators said they will delay opening the 13-lock maritime shipping system for 12 days until April 1 to allow higher levels of Lake Ontario water to be released from Moses-Saunders Dam at Cornwall to stem flooding this spring.

The decision was welcomed news Wednesday by those hoping to head off a very wet spring freshet.

The seaway decision follows several months of rallies and demonstrations by Lake Ontario communities demanding action to bring down high water levels that are now 19 inches above seasonal norms.

Waterfront owners in Quinte and around the lake say they have suffered millions of dollars in damages in two of the last three years due to flooding under regulatory Plan 2014, which governs release of lake water downstream.

Quinte West Mayor Jim Harrison was buoyed by the news Wednesday and expressed high hopes in a phone interview the seaway delay and higher outflows will reduce the threat of forecast high spring runoff and ensuing flooding.

“This is a big plus for us,” Harrison said, “and it means they are taking the water levels down to help protect the shorelines. It’s fantastic news.”

Harrison, Prince Edward Mayor Steve Ferguson and Belleville Coun. Bill Sandison met with Deputy Prime Minister Chrystia Freeland last week in Ottawa to ask for federal assistance to help stem flooding come spring. Harrison also led a rally late last year in Quinte West which drew hundreds of angry waterfront owners demanding action.

In an official announcement, both the Canadian and American corporations jointly overseeing the St. Lawrence Seaway confirmed the system will remain closed until April 1.

It traditionally opens around March 20 in time for spring.

In its decision, the seaway overseers said “based on the current conditions and forecasts provided by the International Lake Ontario-St. Lawrence River Board (ILOSLRB), the majority of benefits of lowering Lake Ontario levels by maintaining outflows above those safe for navigation in the Montreal / Lake Ontario Section of the Seaway occur before April 1, 2020.

“After that date, the benefits for lowering Lake Ontario by maintaining outflows above those safe for navigation are significantly reduced. Due to the dry conditions experienced in February thus far and the record outflows that the ILOSLRB has been able to maintain this winter, the probability of Lake Ontario being above flood levels has decreased and is now only approximately 35 percent.”

Andrew Bogora, communications officer with the The St. Lawrence Seaway Management Corp., told The Intelligencer Wednesday the decision comes after a great deal of consultation with regulators International Joint Commission (IJC) and the International Lake Ontario-St. Lawrence River Board (ILOSLRB).”

He said in a “typical season, the first week [of opening] is not as busy” but said such a closure will result in a large amount of goods being delayed from making their way in and out of the system.

An estimated 40 million tonnes of goods are shipped through the Seaway annually on average, he said.

Asked to put a rough estimate on the amount of goods delayed with stalled shipping, Bogora said 12 days of closure would mean that about 100 cargo ships will not make their way through the system.

“That’s equivalent to 100,000 truckloads on the 401,” Bogora said, or the equivalent of about 30,000 rail cars of goods.

In an advisory issued Wednesday, the IJC said it will boost outflows until April 1 to lower lake levels.

The IJC said “with high levels of Lake Ontario and the upper Great Lakes continuing, the risk of high water this spring remains elevated. Therefore, the board will continue releasing high outflows in the coming weeks by maximizing outflows.”

“Residents along the St. Lawrence River should be aware that water levels could fluctuate significantly over the coming weeks,” said the IJC.

“These deviation strategies will help remove a small amount of additional water from Lake Ontario in the coming weeks. Given the current record high water levels for this time of year on the other Great Lakes, these actions will help reduce the risk of levels on Lake Ontario exceeding 75.50 m (247.7 ft) in 2020.”

The Chamber of Marine Commerce said it is is “disappointed that the opening of the navigation season in the Montreal-Lake Ontario (MLO) section of the St. Lawrence Seaway has been delayed to April 1 to allow more outflow from Moses-Saunders Dam.”

Bruce Burrows, president of the marine chamber of commerce, said in a statement, “Grain exports are ready to go and our food production, steel and manufacturing customers urgently need raw materials as their winter inventories are running out. They cannot afford any further delays that could affect factory operations.”

“Given the current disruption impacting Canada’s national railways, we certainly do not need delays of transportation of critical supplies and products on the Great Lakes-St. Lawrence Seaway transportation and trade corridor.”

“High water levels are negatively impacting residents and businesses, including those that depend on St. Lawrence Seaway shipping, and going forward, we need to work together to develop a much broader, holistic resiliency plan that that looks at every avenue including flood zoning, shoreline resiliency and infrastructure investments for residents and business owners.”