Acoustic Inspection of Sanitary Sewer Lines to Prioritize ... · Acoustic Inspection of Sanitary Sewer Lines to Prioritize Cleaning Operations. PRESENTATION OUTLINE • Acoustic Inspection

Alex Churchill – InfoSense, Inc.Steve Jonson – CH2MHill

March 19, 2014

Acoustic Inspection of Sanitary Sewer Lines to

Prioritize Cleaning Operations

PRESENTATION OUTLINE

• Acoustic Inspection Overview

• Project Background and Objectives

• Summary of Results

• Conclusion





• Conclusion

• Overflows are a Symptom – Not the Problem

WHAT IS THE PROBLEM?

• Cleaning a pipe costs about the same as inspecting a pipe

• >80% of pipes less than 12”, accounts for >90% of SSOs

• Historical GIS – Helpful –But Insufficient

• Where & When to Deploy Cleaning Resources

• Cost Effective & Timely Condition Information

PROBLEM: INFORMATION

INSPECTION METHODS

Manhole Inspection

Push Camera

Zoom CameraACOUSTIC

• CCTV/Robotic Camera• Pipe Wall Defect Scanners• Pipe Profiling / Robotic Multi-Sensor

INSPECTION METHODS

Acoustic

Blockage

Pipe Condition

Pipe Wall DefectDetailed

Pipe Profiling

Insp

ectio

n Re

solu

tion

Relative Cost

HIGH

LOW

HIGHLOW

ZoomCamera

Manhole Inspection

No Contact with Flow: Contact with Flow:

Wastewater PipeCondition AssessmentApplications

Push Camera

CCTV

ACTIVE ACOUSTIC PIPE INSPECTION BACKGROUND

• Patented technology• Gravity-fed sewer focus• Developed in Charlotte with

CMUD as key partner

• Over 3M feet inspected• Rapid assessment helps

better focus cleaning and CCTV resources

ACOUSTIC INSPECTION TECHNOLOGY

• How Does it Work?

ACOUSTIC SCORING

10

5

0

8

2

Obstructed

No Obstructions

Root Fibers Limited GrowthGrease Limited Build Up

Root Fibers and/or GreaseCamera Can Pass

Root Fibers and/or GreaseCamera Cannot Pass

Blockage Assessment 2



HOW MUCH CLEANING IS WASTED?

0 1 2 3 4 5 6 7 8 9 100

100

200

300

400

500

600

700

Blockage Assessment (0-Blocked thru 10-Clean)

Rel

ativ

e O

ccur

ance

9%

14%19%

58%

• Target Historical Problematic Areas

– >50% Pipes Essentially Clean

– <10% Need Immediate Action

• Cleaning a Clean Pipe ⇒Wastes Resources

• Not Cleaning a Dirty Pipe ⇒ SSO

Acoustic Inspection Results~1Million Feet of Pipe

$/fo

ot

Insp

ecte

d

$-

$0.02

$0.04

$0.06

$0.08

$0.10

$0.12

$0.14

at $16/hr

at $33/hr

Feet Inspected/Day

SL-RAT Acoustic Inspection Cost

Municipal Cleaning

~$1.00/foot

Typical Operating

Range Fully Loaded Wage Rate

COST EVALUATION

1

KEY FEATURES OF ACOUSTIC INSPECTION

• No Flow Contact / No Confined Space Entry

• Simple to use – train operators in minutes

• Low Cost–Pennies/foot• Rapid Onsite Results –

Under 3 min./segment• Portable < 30 lbs• GIS Integration – GPS

Enabled• Archive Pipe Segment

Blockage Assessments





• Conclusion

PROJECT BACKGROUND• Ft. Leonard Wood, MO

o Established in 1940o Trains 80,000-90,000

military and civilians every year

o 62,911 acreso 78 miles of sewer lines

o 6” – 42” diametero 41% VCP, 53% PVC, 6% RCP

PROJECT OBJECTIVESSL-RAT is primarily used as a prioritization tool for cleaning/camera operations in 6” to 12” sanitary sewer lines

• Evaluate acoustic inspection as a tool for inspecting sanitary sewer lines

• Compare acoustic inspection results with pole camera

• Compile data of overall system condition at Ft. Leonard Wood





• Conclusion

SUMMARY OF RESULTS• Performed 460 Acoustic Measurements (89,571 ft)

(included several repeat measurements for verification)

SUMMARY OF RESULTS• Acoustic inspection performed in 12 days• 391 unique segments inspected (75,355 ft)

Legend:SL-RAT In FieldPipe Assessment0: 1-3: 4-6:7-10:

FT. LEONARD WOOD

9 10 5 8 6 612

58

154

90

11

0

20

40

60

80

100

120

140

160

180

0 1 2 3 4 5 6 7 8 9 10

8.7% Poor 6.5% Fair84.8% Good

Acoustic Score

#

Histogram of Acoustic Scores





• Conclusion

APPLICATION OF ACOUSTIC INSPECTION

Application Area How to Use Acoustics

Pre-Cleaning AssessmentPrioritize/focus cleaning often see >50% cleaning reduction – “focus on cleaning the dirtiest pipes”

Condition Surveys Quickly & economically assess large areas for asset management & planning

Cleaning Interval Determination

Only clean specific segments when below blockage threshold

Post-cleaning QA Low-cost method to check cleaning effectiveness and prevent downstream SSO’s

Optimize SSES ContractResources

Use acoustics to prioritize pre-cleaning & camera resources for contract advantage

Performance-Based Contracting

Use acoustic inspection to enable SSO targets in cleaning/inspection contracts

Condition Based Maintenance Program

The “holy grail” – economics of acoustics enables a CBM strategy to focus maintenance activity

QUICKHITS

FULLPOTENTIAL

CONCLUSION• Acoustic Inspection was shown to be an Effective

Method to Make Blockage Assessmentso Quicko Cheapo Easy / Safe

• Acoustic Inspection identified pipe blockages that were not picked up by a zoom camera

• Acoustic Inspection Does Not Replace Cleaning or Detailed Inspectiono Helps Determine how to Effectively Deploy Cleaning and

CCTV resources

877-PIPECHK (877-747-3245)[email protected]

www.infosenseinc.com

QUESTIONS?

Acoustic Inspection of Sanitary Sewer Lines to Prioritize ... · Acoustic Inspection of Sanitary Sewer Lines to Prioritize Cleaning Operations. PRESENTATION OUTLINE • Acoustic Inspection

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