Moncton Times and Transcript
Silt raises flood risks
by James Foster
Moncton has doubled its efforts to keep storm sewer outfalls clear of silt in the wake of severe infilling of the Petitcodiac River. “It’s a key issue,” Richard Landry, director of administrative services with the city’s engineering department, said yesterday.
“It’s an ongoing operation. We have to be on our guard all the time.” A massive build-up of silt in the Petitcodiac River beginning at the Moncton-Riverview causeway and going downstream is plugging some storm sewer outfalls, but that’s not a shocking development for such a silty river. However, the silt has built up so tremendously this summer that some environmentalists and scientists say some of the outfalls are now almost completely plugged, with a Department of Fisheries and Oceans scientist finding out last week that at least one city culvert has disappeared completely under the silt.
In the event of rain, water runoff could have no where to go if the outfall is plugged, possibly leading to flooding. Some of the pipes have flaps on them to prevent water from entering them, but allowing water to flow out. On some pipes the silt is blocking the flaps.
Petitcodiac Riverkeeper Daniel LeBlanc calls the silt situation an affront to the environment and vowed yesterday to sue the federal and provincial government to force them to allow the river to flow freely, which in turn would dislodge the silt.
The river, once a kilometre wide in many places, was a pitiful sight yesterday as LeBlanc announced the lawsuit – the water at low tide was just a few metres wide and so shallow that one could see the bottom through the water.
“In the face of this inaction,” LeBlanc said, “we have no choice. This is one of the most endangered rivers in Canada.”
There are fears the tidal bore won’t be able to reach the causeway today – the riverbed is that full of silt. It is believed that such an occurrence would be the first in history. The riverbed is nine metres deep, but is filled with eight metres of silt.
The lack of water in the river is being blamed by some, including LeBlanc, for a pungent smell that has enveloped parts of Metro Moncton in recent days. The theory is that there is no longer enough of a water flow in the river to flush the treated sewage coming out of the Greater Moncton Sewage Treatment Plant.
The plant manager said on Tuesday he was investigating to see if that theory was valid, but yesterday Conrad Allain was not taking phone calls from the newspaper. A spokesman for the provincial Department of the Environment said they were satisfied that the plant operators were checking into the matter. The department has received no complaints from the public about the smell, which comes and goes.
It has been widely expected that an Environmental Impact Assessment on the fate of the causeway would be underway by this summer, but the federal and provincial governments have yet to decide on how to proceed. LeBlanc’s suit will ask that an EIA begin immediately and that the five gates under the causeway that hold water in the headpond be opened.
“We’re taking them to court so that they’ll start the process that they’ve promised us,” LeBlanc said.
Environment Department spokesman Jason Humphrey said the province has not been served with any court documents and had nothing to say about LeBlanc’s avowed action.
“This department is 100 per cent committed to an EIA,” Humphrey said. Kevin Fram, executive assistant to federal Minister of Fisheries and Oceans Herb Dhaliwal, says a suit would be “unproductive,” as it would divert resources and attention from everyone’s common goal: the EIA.
“Everyone agreed in the Metro Moncton area that we need to have this scientific information and this EIA,” Fram said.
“There’s frankly no need for a bunch of lawsuits.”
The siltation problem is much less an issue in Dieppe and Riverview than it is in Moncton, crews there report.
Landry said because of the silt in Moncton’s section of the river, city crews now keep a close eye on weather forecasts despite their increased digging at outfalls, because in the event of heavy rain, they will want to check all the pipes again just to be sure the water can escape.
The problem seems worse the closer the pipe is to the causeway. A traffic circle at the Moncton side of the causeway sometimes floods during rains that aren’t heavy enough to cause problems elsewhere in the city.
“That’s one area we’re watching very closely,” Landry said.
The river typically accumulates silt near the causeway, but periodic opening of the five gates under the causeway allows the headpond to partly drain, with the force of the water flushing out much of the silt.
Drought conditions this summer did not leave enough of a water flow to push out the silt and forced officials to keep the gates closed in order to maintain water levels in the headpond and to prevent silting inside the headpond.