Using Frequent Sewer Inspection to Prioritize Asset Management. May 1, John Schroeder, P.E., BCEE Drew Richards, EI Tim Fallara, P.E.

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1 Using Frequent Sewer Inspection to Prioritize Asset Management May 1, 2014 John Schroeder, P.E., BCEE Drew Richards, EI Tim Fallara, P.E.

2 Agenda Rationale and Goals for Sewer Re-inspection How and why to do sewer re-inspection 2 Case Studies Structural Defects O&M Defects Enhancing Sewer Maintenance and Inspection Programs Benefits and lessons learned from re-inspection Conclusions

Defects O&M Defects Enhancing Sewer Maintenance and

3 Rationale and Goals for Sewer Re-inspection Sewer Defects Change over time O&M Defects are dynamic (grease, roots, deposits) Structural Defects MAY change but they often remain stable without major deterioration mechanisms (cleaning, infiltration, Gw loads, live loads) Determining WHICH defects need to be addressed and WHEN is the most challenging part of sewer assessment Need to identify the locations and causes of: Sewage system surcharging Sewage overflows/backups from manholes or into basements Mitigate and/or eliminate SSO & Basement backups for a selected performance target Don t clean CLEAN pipe and don t Fix Good pipe!

and WHEN is the most challenging part of sewer assessment Need to identify the locations and causes of: Sewage system surcharging Sewage overflows/backups

4 EPA Study for SSO Causes Capacity Concerns 20% MOM Concerns 80%

5 NASSCO PACP Condition Grading System Structural O&M Grade 1 Minor Defects Grade 2 Moderate Grade 3 Fair Grade 4 Poor Grade 5 - Critical

6 Rationale and Goals for Sewer Re-inspection

7 Case Studies Columbus OH & Birmingham AL

8 Livingston/James Sewer System I/I Remediation Project 1,825 WIB complaints in 5 years 439 WIB complaints January 2005

9 Columbus OH 2005 LJII Cleaning & CCTV Program Diameter 8-inch to 96-inch NASSCO PACP v4.2 used May 2005 to February ,180 pipes 700,000 linear feet Significant deposits, roots and structural defects Heavy cleaning of roots and deposits removed from sewers

2 used May 2005 to February 2006 3,180 pipes 700,000 linear feet

10 Pre-Cleaning: March 28, 2005 Rain Event. Sewer flow % full based on modeling results

11 Post-Cleaning: March 28, 2005 Rain Event. Sewer flow % full based on modeling results

12 2013 LJII Cleaning Program Diameter: 8-inch to 12 -inch NASSCO PACP v. 6.0 used CCTV/ PACP Re-inspection 141 pipes (26,000 ) on City request to get 1:1 relationship of.mpg files per inspection Objective Compare sewer defects 8 years later to observe any major changes and better understand the rate of structural deterioration and root growth

13 2013 Cleaning Program

14 Structural Defect Comparison

15 Pipetech, Windows Media Player, and Excel Side by Side CCTV Review

16 2005 New Structural Issues 2013

17 2005 Escalating Structural Issues 2013

18 Minor Changes in Structural Defect

19 2005 Tree Roots at Pipe Joints 2013

20 Blockage Sewer was surcharged High water found in multiple manholes Traced downstream Removed the root blockage 4 days before Thanksgiving Root Blockage Pipe being re-inspected

21 Clearing the Blockage

22 2005 Roots not visible from main Lateral Roots % Blocked 2013 Roots entered mainline % Blocked

23 From Main 2005 Lateral Roots 2005 Looking up the lateral

24 Lateral Roots Roots in laterals are NOT just a private property issue Roots can and will grow into the main and block the main even after mainline CIPP 2013

25 2005 Mainline Grease 2013

26 2005 Mineral Deposits 2013

27 Wet-Weather CCTV Re-inspect CCTV pipes selected from dry weather CCTV & FM data Determine where & How Much infiltration is entering Manholes ; Laterals / Connections Joints ; Defects (holes, fractures, offsets)

28 Jefferson County AL 2012/2013 Cleaning & CCTV Program Consent order Reduce SSOs Sewer Cleaning and Inspection Program 1500 pipes / 400,000 linear feet Removal of roots, grease and deposits from sewers Identify and quantify severity of structural and O&M defects Developed $10M Prioritized CIP Sewer Improvement Recommendations Highest priority replacement, CIPP, & PR done first ($3M) Develop enhanced O&M programs

29 SL RAT Pilot Project Jefferson County, AL 3 month rental / $3k/mo. / 3 man crew 30 to 40 pipes/day (10,000 /day) 1/10 th the time and $ as CCTV 15 % had Scores 0-3 & were cleaned in 1-2 days Transmitter Receiver

30 Jefferson County AL SL RAT Pilot Study Block Poor Fair Good 5.3% 10.4% 25.3% 54.8%

31 Jefferson County AL Chemical Root Control Pilot Study Chemical Root Pilot Project Review CCTV /ID pipes with sig. roots Work order for Dukes Root Control and Vaporooter 2 contracts each about 12 pipes Re-CCTV 4 to 5 months after chemicals applied Evaluate the pre and post and develop a recommendation

32 Before Chemical Root Foam After Chemical Root Foam Jefferson County, AL Before and After Chemical Root Control ~210 feet ~220 feet

33 Before Chemical Root Foam After Chemical Root Foam Jefferson County, AL (MH to A) Before and After Chemical Root Control ~50 feet ~53 feet

34 Before Chemical Root Foam Jefferson County, AL (MH to ) After Chemical Root Foam Huge root grew through hole at 12 oclock Huge root grew through hole at 12 oclock After Root Cutting

35 Conclusions and Lessons Learned Sewer cleaning and inspection is essential to understand the root & blockage problems and most cost effective means for reducing water-in-basement (WIB) complaints & SSOs Owners should consider using additional equipment and crews to keep up with CCTV, cleaning, and reducing SSOs Should develop a frequency for re-cleaning & re-inspection for every pipe and utilize the CMMS accordingly (1 to 10yrs) Cleaning programs must evolve over time and adapt frequency based upon lessons and debris removed from pipe after each cleaning. Roots are HUNGRY and THIRSTY. They grow back quickly and should be controlled through maintenance programs; chemicals root-control, and/or sewer rehabilitation

36 Conclusions and Lessons Learned Structural defects tend to degrade at an unpredictable rate and not in a linear fashion. Re-inspection helps develop a RATE of deterioration Sewers with significant cracks and fractures should be reinspected much sooner than a sewer with no structural defects and may not need rehabilitation for several years PACP numbering systems provide a general severity that can be used for querying. It should NOT be used for a detailed rehab. program. Proactive PACP CCTV inspection is the best way to maximize the life of the sewer; prevent catastrophic failures AND optimize your maintenance costs

37 Questions??? For More Information John P. Schroeder, P.E., BCEE, CDM Smith Drew Richards, E.I. CDM Smith C. Timothy Fallara, P.E., City of Columbus

38 GIS Data Correlations Legend Repeated WIB complaints during large storms Model-Predicted Capacity-Deficient Areas Root locations C-2-02

39 Sewer Main Assessment Structural Condition Sewer Defects Cracks Fractures Broken Holes Collapses Offset Joints

40 Sewer Main Assessment Deposits Grease Encrustation Settled Roots Infiltration O&M

Interactive Decision Tree Automates Sewer Rehabilitation Planning

Interactive Decision Tree Automates Sewer Rehabilitation Planning IWPCA Annual Conference June 5, 2008 Rodney Moeller, P.E., John Schroeder, P.E. BCEE, C. Timothy Fallara, P.E. & Mel Meng, P.E. Agenda