#Japan #Fukuoka #Liberaware #Environmental Development

A New Era in Sewer Inspection Technology in Fukuoka City

In a significant advancement for infrastructure maintenance, Liberaware, a company based in Chiba, has conducted a groundbreaking field test in Fukuoka City focusing on sewer inspections. This initiative, in collaboration with Environmental Development and the city of Fukuoka, aims to realize a 'No Entry' inspection system, minimizing the need for personnel to enter sewer pipes during assessments.

Background and Purpose

This project arises in the wake of a severe road subsidence incident in Yashio City, Saitama Prefecture, in January 2025. Following this event, a nationwide special survey unveiled that approximately 748 kilometers of sewer pipes across Japan require urgent attention. The need for inspections, particularly for pipelines with a diameter of 2000 mm or less, is expected to increase, making the safeguarding of worker safety and enhancing inspection efficiency critical challenges.

Traditional sewer inspection methods have been essential for infrastructure maintenance; however, the industry is increasingly calling for 'No Entry' approaches. This shift necessitates the development of high-precision inspection technologies to ensure safety and effectiveness. Against this background, the technology verification conducted is a promising step toward validating next-generation inspection methodologies within practical environments. The work primarily focused on rainwater systems as part of ongoing sewer research endeavors.

Execution and Evaluation Criteria

With support from Environmental Development and the city of Fukuoka, the field tests utilized a drone equipped with distance measurement and damage assessment technologies. The evaluation centered on two main aspects:

1. Accuracy of Distance Measurement Technology: Assessing distance measurement precision compared to actual measurements in non-GPS environments within the pipes.
2. Effectiveness of Damage Detection and Measurement Features: Systematic extraction of damage locations like cracks based on aerial footage, coupled with accuracy evaluation of non-contact dimension measurements.

Outcomes of the Verification

The verification demonstrated that the drone successfully reached the endpoints of the pipeline without delays, allowing for detailed insights regarding the condition of the sewer infrastructure. In the area of damage measurement, the drone recorded damage widths as narrow as 2 mm, with an error margin of just 5%. Moreover, it effectively recognized all previously identified damage areas mentioned in prior TV camera inspections, significantly shortening inspection times—underscoring high practical efficacy.

Distance measurement results also confirmed its practical application, achieving efficacy comparable to traditional methods and further minimizing risks associated with human entry into confined spaces. The establishment of this technology represents a substantial progress toward sustainable maintenance of the identified 748 km of sewer systems and efficient screening of extensive pipeline environments.

Insights from Environmental Development

A spokesperson from Environmental Development highlighted that the verified functions of the drone significantly contribute to achieving efficient and detailed inspections. The drone's ability to gather clear diagnostic information from challenging environments, where traditional methods fall short, marks an important achievement for future maintenance improvements. The company is committed to leveraging such technologies to enhance the safety of regional infrastructure.

Future Prospects

Looking ahead, further validations will continue under broader conditions, including pipes with diameters under 2000 mm, expanding the technology's applicability and striving for greater accuracy. In tandem, efforts will be directed toward establishing efficient operational models that do not necessitate personnel entering the sewer lines, thereby promoting a transition to 'No Entry' inspection methods gradually. Liberaware aims to integrate unique drone and data analysis technologies to realize sustainable and safe sewer maintenance, contributing to the resilience of national infrastructure.

About Environmental Development

Founded in 1964, Environmental Development is based in Fukuoka City and specializes in the cleaning, maintenance, repair, and rehabilitation of public infrastructures, including water supply and sewerage systems, roads, and parks. Focused on “comfort and beauty,” the company has committed to maintaining the social infrastructure that supports local communities, relying on years of field experience and unique technology development for creating a safe and sustainable urban environment.

About Liberaware

Liberaware is dedicated to ensuring a safe society with a mission to develop world-class drone technology specialized for inspecting hazardous indoor environments. Their innovative solutions not only include drone inspections and analytics but also the visualization of hidden risks, ultimately contributing to greater societal safety and peace.