Town “monitoring” high water levels

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The town of Deep River says it is “monitoring” the high water levels in the Ottawa River, and encourages anyone impacted by the risk of flooding to call for help.

The town issued a press release Wednesday morning noting that the municipal emergency control group met Tuesday afternoon to review the impact of the Ottawa River’s near-historic high levels.

“The emergency control group is closely monitoring the water level of the Ottawa River.

“Given the forecast from the Ottawa River Regulation Planning Board and the current level of the Ottawa River, the control group has established a plan to deal with local impacts of the Ottawa River’s rising water level,” the town stated.

“Deep River’s public works, police and fire crews have been closely monitoring properties along the Ottawa River and offering assistance to residents.

“Mayor Sue D’Eon stated ‘Residents have been grateful for the presence and help offered by volunteers and town staff. The efforts of everyone to help is greatly appreciated.’

“Deep River residents along the Ottawa River impacted by flooding may call town hall at 613-584-2000, or for public works related emergencies after hours and on weekends at 1-800-342-6442.”

According to the river regulating board, the water levels in the Pembroke reach of the river (including Deep River) were at 113.47 m above sea level as of Tuesday afternoon, and are expected to peak at 113.6 m on Thursday.

Historically, according to records kept by the board, the river has only reached that level once before in the years since 1950, when it hit 113.67 m in 1967.

Aside from the impact on individual homes and properties, one of the town’s main concerns is the effect of high water levels on the town’s wastewater (sewage) treatment plant.

According to the town’s press release, the Ontario Clean Water Agency (OCWA), operators of Deep River’s water and sewage treatment plants, “reported (Tuesday) that the level of the Ottawa River has risen significantly in the past 24 hours.”

“OCWA’s staff is monitoring the situation 24/7. There is a concern that if water levels continue to rise, operators, with MOE approval, must adjust the secondary treatment process.

“OCWA has obtained a temporary permit from the Ministry of Environment, Conservation and Parks should the adjustment be required.”

The press release Wednesday morning follows a public notice the town issued Tuesday afternoon asking residents to help the situation by reducing their water use by things like turning off their taps, flushing less often and taking shorter showers.

“Water conservation will help reduce the risk of the plant operating over capacity during this year’s spring melt,” the notice stated.

According to Wikipedia, sewage treatment “generally involves three stages, called primary, secondary and tertiary treatment.”

“Primary treatment consists of temporarily holding the sewage in a quiescent basin where heavy solids can settle to the bottom while oil, grease and lighter solids float to the surface. The settled and floating materials are removed and the remaining liquid may be discharged or subjected to secondary treatment…

“Secondary treatment removes dissolved and suspended biological matter. Secondary treatment is typically performed by… water-borne micro-organisms in a managed habitat. Secondary treatment may require a separation process to remove the micro-organisms from the treated water prior to discharge or tertiary treatment.

“Tertiary treatment is sometimes defined as anything more than primary and secondary treatment in order to allow ejection into a highly sensitive or fragile ecosystem (estuaries, low-flow rivers, coral reefs…).”

Although prompted by this year’s extremely high water levels, concerns about flow and capacity at the town’s sewage treatment plant are nothing new.

OCWA manager Brad Sweet told members of the town’s public works committee in April 2013 that the plant was working harder than it need be, no thanks to groundwater infiltration.

Sweet appeared before the committee after council raised concerns regarding OCWA’s 2012 annual report on the town’s sewage treatment plant (STP).

Although the 2012 annual report gave the sewage treatment plant a clean bill of health in terms of meeting all the ecological parameters laid down by the Ministry of Environment, council members had questions about capacity issues at the facility.

In 2012, the report stated, the average daily flow at the STP was 79.9 percent of its current designed capacity, while maximum daily flows were 24 percent over its designed capacity of 2,727 cubic metres per day.

That being said, the figure of 79.9 percent was down significantly from 2011, when the average daily flows at the plant were running at 90 percent of its capacity.

Mother Nature, Sweet told members of the public works committee, played a significant role in that reduction.

“Last year we had an extremely dry summer, and that affected that number,” said Sweet, who noted that a lack of rain mean less groundwater infiltration into the system.

“If you have a perfectly sealed system, it’s linear. But if it’s not sealed, and the older it gets, the more susceptible it is (to infiltration).”

Sweet said OCWA’s own lab testing, showing reduced levels of suspended solids in the volumes being treated at the plant, confirm its suspicions.

“It’s very indicative of infiltration,” Sweet said. “We’re treating a lot of water.”

Sweet said it would be in the town’s best interests to try and solve the groundwater infiltration problem sooner rather than later.

“It’s a lot easier to treat dirty water than clean,” he said of the water entering the STP containing lower numbers of suspended solids.

“We’re not doing ourselves any favours. You’re taking up capacity and it’s harder to treat.”

(Photo: Normally located at the top of a three-foot bank overlooking the Ottawa River, a bench at Deep River’s pumping station park has water lapping around its feet in a photo taken before the river reached this week’s new high levels.)