Research Trends and Results
Empirical Studies of B-DASH Project (Sewer Management SystemTechnology)
OGAWA Fumiaki, Head; FUKATANI Wataru , Senior Researcher; SUEHISA Masaki ,Researcher; KAYA Takuro , Guest Research Engineer
Wastewater System Division, Water Quality Control Department
Keywords: B-DASH, sewer management system, screening survey
1. Introduction
In order to prevent road cave-ins and similar disasters
resulting from damage to sewers, and to extend the life ofsewers, efforts are being made to implement systematic
inspections and surveys. However, it is difficult to deal
with an enormous amount of sewer stock under thesevere financial condition of local governments and thedaily working volume in the current TV camera survey.
It is, therefore, strongly required to develop an efficient
survey method by combining various existing sewer
inspection technologies.
2. Breakthrough by Dynamic Approach inSewerage High Technology Project (B-DASHProject)
MLIT started the Dynamic Approach in SewerageHigh Technology (B-DASH) Project in fiscal 2011. In
fiscal 2013, in order to reduce maintenance costs andimprove the ratio of inspections and surveys conducted, aresearch agreement on validating sewerage management
technology was executed with 3 joint researchorganizations.
3. Outline of the sewer management systemtechnology(1) In-pipe camera inspection, wide-angle view
camerasurvey,andprofiling technology
This technology is forin-depth
study
using
a
wide-angle camera and pathshape profiling system after
screening sewers with major
abnormality using an in-pipe
camera and a conductance meter.
(Kansei Kogyo Co., Ltd., Nissui
Figure 1: In-Pipe
Con and Hachioji City Joint
CameraResearch Organization)(2) Wide-angle camera
survey and shock elastic wave inspection
technology
This technology screens sewers with major
abnormality using a wide-angle camera capable ofdetecting the in-pipe condition efficiently only withdirect-view driving mode, and then examines the detected
sewers to calculate the load bearing capacity of pipes byshock elastic wave inspection method and determine
control measures. (Joint Research Organization ofSekisui Chemical Co., Ltd., Urban Infrastructure
Technology Center Foundation, Kawachi-Nagano City
Receiving
part

Elastic wave

HammerFigure 2: Image of Shock Elastic Wave
Inspection Methodand Osaka Sayama City)(3) Advanced image recognition technology
This technology contributes to labor-savings andefficiency improvement in surveys by using apower-loaded self-propelled TV camera capable ofspherical imaging without stopping, learning-type
automatic defect detection, and defect detection by laser
projection.
(Joint research organization of Japan
Sewage Works Agency, NEC Corp., and Funabashi City)

Figure 3: TV Camera with Advanced Image
Recognition Technology
4. Utilization of findings from empirical studies
NILIM clarified the efficiency and required
performance of surveys done with each of theaforementioned three technologies by comparing daily
progress, survey costs, detectable defect items, accuracy,scope of application, applicable conditions, etc. withconventional survey methods. In the future, we plan toformulate guidelines (draft) for efficient surveying ofsewers using these 3 technologies, which we hope willserve as a reference for local governments, survey
companies, and equipment manufacturers.
[Reference]
http://www.nilim.go.jp/lab/ebg/index.htm