Calgary, Alberta - Project Overview

CH2M HILL is assisting the City of Calgary in conducting a Condition Assessment Smoke Testing Program of some of the City's wastewater collection system.

A Conveyance Condition Assessment or Sanitary Sewer Evaluation Survey (SSES) may consist of all or some of the assessment elements described below. The scope of the current project includes Smoke Testing, CCTV Inspection services, and Dyed-Water Testing.

Wade Smoke Testing Services


Conveyance Condition Assessment and Evaluating Sanitary Sewers

Inflow and Infiltration (I/I) are common terms used for the introduction of excess water into a Sanitary Sewer System or Wastewater Collection System. This is typically in the form of rain and runoff from storms. The wastewater collection system is not designed to handle such volumes of water as a storm can produce, so it becomes vitally important to identify where this water is entering the system. If too much water is entering the collection system, it can lead to sanitary sewer overflows (SSOs), sewage backups, and escaping of waste substances and chemicals. In this project, Conveyance Condition Assessment or Sanitary Sewer Evaluation Study (SSES) elements include:

Smoke Testing
CCTV Inspections
Dyed-Water Inspections
Smoke Tests: Often referred to as a "rainfall simulation" test, smoke testing is used to detect I/I sources in both the private and public sectors of the collection system. Smoke testing is performed by placing a smoke generator into the intake chamber of a high-capacity blower placed over an isolated sewer pipe segment. Field crews monitoring the area document locations where smoke escapes the system at a system defect or I/I source. Although not a defect, one common escape route for smoke is the "vent pipe" - The pipe emerging from the roof of a private dwelling that allows the escape of sewer gasses before they enter the residence.  The smoke that can be seen coming from vent pipes or rising from areas in the ground is: 
NON-TOXIC, HARMLESS, ODORLESS, AND CREATES NO FIRE HAZARD.
>>Typical Smoke Test Program Video 
CCTV Inspections: This process involves transporting a closed-circuit TV camera through a sewer pipe. Engineers and technicians view the resulting footage and glean valuable data on conditions of the sewer pipe.
Dyed-Water Testing: Sometimes a simple visual inspection of a suspect I/I source cannot confirm if the source is connected to the sewer system. In this case, crews will introduce dyed-water into the suspect source. If dyed water shows up in the sewer system, the leak will be confirmed. This makes identifying leaks and breaks in the pipe much easier to identify.