Wastewater collection and treatment

Wastewater is water that has been used and discharged by homes, businesses and industrial sources. It is 99.9 percent water by weight, with a very small portion (0.1 percent) of dissolved and suspended solids.

Before it is returned to the Ottawa River, Wastewater is thoroughly treated at the Robert O. Pickard Environmental Centre (ROPEC) to ensure it is safe for the public’s health and the environment. ROPEC collects wastewater from more than 90% of Ottawa's population. For a detailed description of this treatment process, download our wastewater treatment brochure: Let's Explore Wastewater Treatment.

Treatment process

1. Preliminary:

• Coarse screening/pumping: Wastewater flows to the plant through enormous pipes buried deep in the ground. Once the wastewater arrives at the treatment plant, any object bigger than a shoe gets screened out.
• Fine screening: Screens will catch smaller objects like sticks and rags.
• Grit removal: Degrit tanks separate pebbles, grit and sand from the other solids that can be further treated.

2. Primary:

• Removal of settled solids (sludge) and floatable material (scum).

3. Secondary:

• Naturally occurring bacteria remove dissolved and suspended organic pollutants. Removal of phosphorus takes place by adding a solution of iron to the wastewater. Iron captures the phosphorus, creating a solid that can sink and be separated from the water. 

4. Disinfection:

• Before it is finally returned to the Ottawa River, the treated water is first disinfected using sodium hypochlorite, year round.

Process control

Protecting the health of the Ottawa River is an important part of treating wastewater. Processing of wastewater or sewage is monitored 24/7. Sensors throughout the plant allow staff to monitor the treatment process and notify them of any problems. The monitoring and testing program ensures quality targets are met and potential process problems are identified early.

Generating electricity at the Robert O. Pickard Environmental Centre (ROPEC)

As wastewater is treated and processed, methane and carbon dioxide are produced. In 1998 a process was added to convert these gases into electricity and heat through a process called cogeneration. Cogeneration produces 5 megawatts of heat and electricity which provides 50% of ROPEC's energy needs on an annual basis. The cogeneration facility produces enough electricity for approximately 1,500 homes.

Performance

The Robert O. Pickard Environmental Center meets all provincial guidelines for wastewater effluent as defined by the Ontario's Ministry of the Environment, Conservation and Parks (MECP).

Actual volume of wastewater treated at the Robert O. Pickard Environmental Centre

About the Robert O. Pickard Environmental Centre (ROPEC)

• Provides secondary level treatment (physical and biological) of domestic, commercial and industrial wastewater - returning treated water to the Ottawa River.
• Situated on 67 hectares of land adjacent to the Canotek Business Park in Ottawa East. 28.4 hectares remains available for future growth.

History

• Originally built in 1962, providing primary level treatment, and called the Green’s Creek Pollution Control Centre.
• Expansions in 1971 and 1975 to provide needed capacity for the growing City.
• Major expansion and rehabilitation from 1988 to 1993 increasing treatment capacity, improving biosolids processing, and adding odour control. Level of treatment improved from primary treatment to include biological secondary treatment.
• Renamed for Robert O. Pickard, retired Commissioner of Works in the former Regional Municipality of Ottawa-Carleton.
• Mr. Pickard helped initiate an expansion and upgrade of the centre to provide Ottawa with improved wastewater treatment capacities.
• Addition of dechlorination process in 2013 to remove chlorine prior to discharge of treated water to the Ottawa River.

Ottawa's wastewater collection system gathers wastewater from homes, businesses and industrial sites, transporting it through a network of sewers, pumping stations and forcemains to trunk sewers. The wastewater then flows to the Robert O. Pickard Environmental Centre for treatment.

Ottawa’s wastewater collection system covers 2,796 square kilometres and extends from West-Carleton to Cumberland. It includes:

• 2,846 km of sanitary sewers
• 108 km of combined sewers
• 71 wastewater pumping stations
• More than 92,000 manholes
• Approximately 234,000 service connections
• Sewer pipes ranging in size from 20 cm to three metres in diameter

In the rural areas, a variety of collection methods are used:

• Richmond, Munster Hamlet and Carp are connected to the municipal trunk system.
• Elsewhere individual septic systems are used and the sludge from septic tanks is transported to the Robert O. Pickard Centre for treatment.

Who do I call if there is a strong sewer smell coming from outside my home?

Call 3-1-1.

What to do if there is a strong sewer smell coming from the basement?

To prevent smells from the sewer entering your home, the plumbing in your basement has a "trap" installed that creates a barrier when filled with water. The trap is under the floor in the basement and is the first place to look if you have odours in your home.

• Sometimes in older homes the water in the trap leaks or evaporates and the barrier is broken. To reintroduce the barrier, pour a few cups of water in the basement floor drain.
• In newer homes, the trap in your home is kept full through a discharge from the trap seal primer valve. If this odour occurs in newer homes, check to see if the primer valve is operating properly or call a plumber.

If the smell persists after a few hours or if the smell is from a sewer back-up, please contact 3-1-1.

What to do if there is an offensive odour coming from one of my sinks?

Often residents may experience an offensive odour while near a sink or after filling a glass. If you think the odour is from the glass of water, take the glass to another room. If you no longer detect the odour from the glass, it may be the sink that is the source of the odour. Often a small amount of commercial drain cleaner will remove any material collected in the trap of the sink that is creating the odour.

The Robert O. Pickard Environmental Centre (ROPEC) is designed to divert wastewater flow in emergency situations. There are two types of diversions:

• Bypass: The wastewater receives partial treatment. Solid materials are removed from the wastewater and harmful bacterial are reduced before it is released to the river.
• Overflow: The wastewater receives the lowest level of treatment. Harmful bacteria are reduced before it is released to the river.

The practice of bypassing and overflowing is accepted by the Ministry of the Environment, Conservation and Parks (MECP) during an emergency or if written permission is given by the MECP. In Ottawa, these events are monitored and reported to the MECP and downstream users such as water purification plants.

Bypass Activity (August 24, 2018 to date)

Overflow Activity (August 24, 2018 to date)

There have been no overflow events.