WASTEWATER
Using a camera nozzle and chain cutter to efficiently handle blocked sewers
W
hen municipal sewer or storm lines become blocked, the trouble typically began with a growth of tree roots that eventually stopped the free flow of wastewater. Blockages can also occur due to accumulated hard mineral deposits, grease, silt, or debris. The resulting blockage can lead to sanitary sewer overflows, which can cause environmental and property damage. The skillful use of high-powered nozzles with forward penetrating jets can sometimes dislodge partial obstructions in smaller pipe. However, resolving the worst cases in large pipe requires the use of special heavy-duty chain cutter nozzles that can remove even a “wall of roots”. “For smaller clogs a contractor can use
forward-penetrating nozzle jets to clear it. A mini chain cutter might be required for light to medium roots. But, any pipe 1,300 mm or larger with heavy roots or heavy mineral deposits will need a tool with more power and capability,” says Dan Story, operations manager at KEG Technologies, a manufacturer of sewer and storm line products, including nozzles, chain cutters and camera nozzle systems. Contractors must be cautious, however, when placing cutters into sewer lines to avoid severing utility lines. “Before a root cutter is inserted into the line, it should be inspected by camera first to prevent cutting a gas or power line and causing sparking and explosion,” says Story. “The most efficient way to inspect the area is with a camera noz-
zle that takes video while cleaning.” Although a variety of visual inspection options are available, not all are economical in terms of time and labour. Sending a CCTV camera crew to acquire video in a sewer line is common. However, this usually involves taking them off other tasks, such as documenting pipe condition. The sewer cleaning team must also wait for the CCTV crew to arrive and take video before the source and severity of the blockage is identified. Inevitably, this leads to additional production downtime. Portable video recording devices, such as a nozzle and camera mounted inside of a carrier exist, but are typically not reliable. Some camera nozzles are specifically designed and integrated for
RVA Welcomes
STEWART STEWA T DICKSON Manager, Municipal Conveyance
Over 22 years of municipal engineering experience
Career Opportunity Blue-White is seeking a motivated business development leader for the Canadian marketplace. The position of Business Development Manager includes responsibility for sales of all Blue-White products and services with the goal of expanding our company footprint in the Canadian metering pump and flow measurement landscape. If this opportunity excites you, please contact us at jobs@blue-white.com
Fluid Metering Solutions Made Simple rvanderson.com
46 | December 2021
www.blue-white.com Environmental Science & Engineering Magazine
