Taking care of our Sewage Collection System

NOTICE - 2025 Sanitary Sewer Flushing

Please be advised that sanitary sewer flushing of the sanitary sewer system will be taking place in Rockwood commencing on September 22 until early October to remove grit, sand, gravel and greases from the sewer mains.   This is a preventative maintenance operation that helps prevent sewer blockages, odour generation and premature wear on mechanical components.  The work will be completed between 8 am and 5 pm Monday to Thursday.

What is a Sanitary Sewer System

Rockwood has a sanitary sewer collection system which transports wastewater from homes and business to the centralized location for treatment.  In the case of Rockwood, that treatment is ultimately provided at the City of Guelph  wastewater Treatment Plant.  The Rockwood system has over 20 kilometers of gravity sanitary sewers, and five sewage pumping stations and one pretreatment plant which sends sewage to Guelph.  The sewers within Rockwood rely on gravity to function and provide minimum flow velocity to keep the sewers clear and flowing.  Over time materials such as grit, sand gravel and greases settle out and remain in the sewers with the potential to case to backups and sewer surcharging which can result in damage to property.  Preventative maintenance in the form of sewer flushing is completed to ensure that the gravity sewers continue to flow freely preventing blockages, odour generation and premature wear on mechanical components within the pumping stations. 

What Is Sewer Flushing?

Sewer flushing is a preventative maintenance process necessary to remove settled and accumulated material within the gravity sanitary sewers to eliminate the potential for sanitary sewer main surcharging. 

During this process a flushing contractor sets up equipment at manholes in the roadway to release pressurized water through the sanitary sewer main, removing any buildup.  As a result, a bubbling and/or vacuum effect may be noticed in your drains or toilets.  If a residents begin to notice this occurring, it is recommended that you close all toilet seats and cover any floor drains during the flushing period. In addition, in order to eliminate the potential of sewer gas migrating into home, it is important to refill all plumbing traps by running water in your sinks and floor drains after work is complete. 

During the cleaning process, air pressure is created inside the sewer pipe. Most of the time, the pressurized air escapes with no impact. In some instances, the air can only escape through the service connection between your house and the Town’s sewer system, and will expel through the internal plumbing vents without incident.

In some cases a blocked sewer pipe or vent within a home may result in a more significant air pressure release or blowback through a toilet or floor drain.  The liquid which blows back is either the flushing water used in the process or the liquid contained within the toilet.  Unpleasant odours may also occur.  Should you experience a significant blowback, it is recommended you check your plumbing (ideally by a certified plumber) to ensure that your service connection and vent pipes are clear of debris and are functioning properly.

Don't Flush Other stuff!

What you put down your drain or flush down your toilet can negatively impact the environment and it can also create sewer blockages and back-ups.

Items to NOT Flush Down the Toilet or Pour Down the Drain

Below is a list of just some of the items that should not be flushed down the drain:

  • Paper products - facial tissue, paper towel, cardboard, etc. The only paper product that should be flushed down the drain is toilet paper.
  • Grease
  • Food Waste
  • Rags
  • J-Cloths
  • Paper towels
  • Feminine Hygiene Products
  • Face Wipes, Baby Wipes, Sanitary Towelettes (manufacturers often say these products are "flushable"; however the reality is they cause blockages in our waste water system)
  • Bandages
  • Cotton Wool / Cotton Buds
  • Diapers
  • Household Hazardous Waste
  • Kitty Litter
  • Dental Floss
  • Medication

For more information on how to dispose of the items listed above, visit Wellington County Solid Waste Services.

Grease

  • Never pour grease down the sink drain or toilet. Grease cannot be broken down effectively during the wastewater treatment process. Grease that is flushed down the pipes can block sewer pipes.
  • Grease clings to pipes and builds up over time.
  • Cold weather solidifies grease.
  • Blocked sewage (sewer backup) can surge up through sinks, floor drains and toilets and make for a very, very messy cleanup.

How to Dispose of Grease Properly

  1. Allow grease to solidify, scrape or use a paper towel to dispose into the GREEN bin. Household hint: store edible food oils in a plastic container until it solidifies, then cut plastic away from grease and throw in GREEN bin.  Plastic goes into the BLUE recycle bin. 
  2. For oils that do not seem to solidify, store edible food oils in a recycle plastic container, FREEZE, cut plastic away from grease, dispose into the GREEN bin.
  3. Before washing dishes, scrape hardened grease into the GREEN bin.

And remember: All storm sewers lead to your water.

  • The storm sewer system drains into rivers, streams and lakes, and can seep into the ground.
  • What goes in the storm sewer can contaminate the sources of our drinking water

Sewer blockages

Signs of a sewer blockage include:

  • Toilets, basins, baths or tubs are slow to empty;
  • Toilets overflow or fill higher than usual;
  • Gully-traps or Overflow Relief Gully in the yard overflow when the toilet is flushed, when basins or baths are released;
  • Overflowing sewer access chambers (manholes);
  • Gurgling noises in the sanitary drains.

Causes of a sewer blockage include:

  • The illegal connection of storm water sumps or downpipes to the sewer causing them to overflow when it rains.
  • Wastes that are not intended for the sewer, choking the system and leading to backflows of sewage within the property;
  • Tree roots entering through drainage pipes, faulty joints or loose inspection openings; cracked sewer pipes that have been damaged by movement of the sub-soil, penetration of rocks, increases the risk of bad and leaking pipes or connections; and
  • Changes to the property by overloading the ground with retaining walls, building structures and vehicular traffic also can cause crush or flatten sewer pipes.

Sewer pipes can block:

  • In any part of the sanitary drain within the property;
  • In the point of connection (POC) where the sanitary drains connect to the Municipal line;
  • In the Municipal line (between the main and the POC); and
  • In the Municipal sewer main and access chamber (manhole).

What to do if the sewer blocks:

The Guelph/Eramosa Township does not provide services for clearing blockages on private property.  However, you may contact the Township Office to determine whether the blockage is on public or private property.

  1. If the blockage is found to be on private property, outside of regular working hours of 7:30 a.m. to 3:30 p.m., relevant costs in providing this service will apply.
  2. If the blockage was caused by tree roots in the Township’s point of connection (POC), sewer main or outside property boundary the fee will be absorbed by the Township.
  3. Private plumbers are not permitted to clear blockages that are located within the Municipal sewer main, this service may be procured by wastewater staff only.

Here is a list of items to consider if you suspect your sanitary sewer from your house to the main is plugged.

  • Call a reputable plumber that is licensed.
  • Ask if the plumber has video inspection equipment available to examine your pipes before and after the cleaning process is completed.  This will help in determining the location of the blockage and to ensure the blockage is cleared.   
  • Ensure this plumber is able to make a copy of this video inspection which will identify any deficiencies within the pipe, from your home to the sewer mains. This is an important step, for if the video reveals the pipe is damaged on the Town’s property, the costs related to the pipe cleaning and video recording may be the responsibility of the Township.

WHO IS RESPONSIBLE IN MAINTAINING MY SEWER LINES?

The maintenance of private sanitary drainage lines is the sole responsibility of the property owner.

If you have any queries about the information presented, please contact the Public Works Department (Water/Wastewater) at 519-856-9596 ext. 122.