Scandinavian Program Applies Phased Sewer Assessment Approach

Posted by Olivia Singer on Nov 20, 2019

Envirosight’s Phased Assessment Strategy for Sewers (PASS) was built with the goal of working smarter, not harder, to solve the most pressing issues facing the wastewater industry. Many municipalities and sewer professionals lack the time, money and resources needed to maintain deteriorating systems.

Envirosight Field Inspection

PASS combines existing and new technologies into a single, integrated workflow to systematically inspect pipes without wasting resources.

This concept has been validated by a similar approach developed in Scandinavia called the Condition Assessment and Sewer Inspection (CASI). The CASI Guide Book highlights different methods for inspecting sewer pipes beyond CCTV and argues, more broadly, for improving asset management to reduce wasted resources and increase safety.

In Finland, water system asset management has long been inadequate, according to CASI, with risk assessments, and condition and rehabilitation management scarcely implemented. The age of a pipe and CCTV footage are typically the only data gathered from a line, which means some substantial quantitative data is ignored or overlooked. And the inspections that are being completed are often infrequent.

“Annually, less than 4% of the total network length is inspected, which means that there is an approximate 25-year lifespan for a certain section of pipeline to be inspected,” the CASI Guide Book states. “During that period, the condition of the sewers (and other pipelines) change considerably, with no repairing methods for breakages or inflow and infiltration being made.”

Many utilities are unaware of the other options for sewer inspection beyond CCTV, according to CASI, and aren’t educated on how to effectively designate resources to pipe condition and rehabilitation management. 

“CASI methods vary greatly from city to city and from town to town,” according to the Guide Book. “This pinpoints the need to make stronger guidelines for inspection methods, terminology, condition classification, and rehabilitation/renovation methods. If the network information is high in quantity and it is geographically coded, the effects from a lack of data are minimal.”

Similarly, Envirosight’s PASS program aims to help utilities gather a wider range of data using diverse technologies, thus helping them allocate resources more efficiently. Its three phases include completing a zoom camera survey to see if a pipe needs additional attention; using a video nozzle for post-cleaning assessment; and using a CCTV crawler only for pipes that need a thorough inspection. 

Both PASS and CASI strive to assist utilities in developing more effective asset management, ultimately decreasing costs and labor time associated with sewer inspections while utilizing both old and new, innovative technology in the industry.

Learn more about PASS and how it can help you work smarter, not harder.

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