WEB-BASED DATABASE ON
RENEWAL TECHNOLOGIES
&EPA
United States
Environmental Protection
Agency
EPA/600/R-16/086
August 2016
www.epa.gov/water-research
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WEB-BASED DATABASE ON RENEWAL TECHNOLOGIES
by
Wendy Condit, P.E., John C. Matthews, Ph.D., and Ryan Stowe
Battelle Memorial Institute
Shaurav Alam, Ph.D.
Louisiana Tech Trenchless Technology Center
EPA Contract No. EP-C-11-038
Task Order No. 01
Ariamalar Selvakumar, Ph.D., P.E.
Task Order Manager
U.S. Environmental Protection Agency
National Risk Management Research Laboratory
Water Supply and Water Resources Division
Urban Watershed Management Branch
2890 Woodbridge Avenue (MS-104)
Edison, NJ 08837
May 2016
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DISCLAIMER
The U.S. Environmental Protection Agency (EPA), through its Office of Research and Development,
funded and managed the research described herein under Task Order (TO) 01 of Contract No. EP-C-11-
038 to Battelle. It has been subjected to the Agency's peer and administrative review and has been
approved for publication. Any opinions expressed in this report are those of the authors and do not
necessarily reflect the views of the Agency, therefore, no official endorsement should be inferred. Any
mention of trade names or commercial products does not constitute endorsement or recommendation for
use. Case study data was collected from publically available information. The quality of the case study
information and secondary data referenced in this document was not independently evaluated by EPA and
Battelle.
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ABSTRACT
As U.S. utilities continue to shore up their aging infrastructure, renewal needs now represent over 43% of
annual expenditures compared to new construction for drinking water distribution and wastewater
collection systems (Underground Construction [UC], 2016). An increased understanding of renewal
options will ultimately assist drinking water utilities in reducing water loss and help wastewater utilities
to address infiltration and inflow issues in a cost-effective manner. It will also help to extend the service
lives of both drinking water and wastewater mains. This research effort involved collecting case studies
on the use of various trenchless pipeline renewal methods and providing the information in an online
searchable database. The overall objective was to further support technology transfer and information
sharing regarding emerging and innovative renewal technologies for water and wastewater mains. The
result of this research is a Web-based, searchable database that utility personnel can use to obtain
technology performance and cost data, as well as case study references. The renewal case studies include:
technologies used; the conditions under which the technology was implemented; costs; lessons learned;
and utility contact information. The online database also features a data mining tool for automated review
of the technologies selected and cost data. Based on a review of the case study results and industry data,
several findings are presented on trends in the water and wastewater renewal market and opportunities for
future improvements. The database can be accessed at: http://138.47.78.37/Retrospective.
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ACKNOWLEDGMENTS
This report has been prepared with input from the research team, which includes Battelle and the
Trenchless Technology Center (TTC) at Louisiana Tech University, and Dr. Ray Sterling. The technical
direction and coordination for this project were provided by Dr. Ariamalar Selvakumar, the EPA Task
Order Manager. The project team would like to thank the water and wastewater utilities and technology
vendors that provided case study information.
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EXECUTIVE SUMMARY
As U.S. utilities continue to shore up their aging water and wastewater infrastructure, renewal needs now
represent over 43% of annual expenditures compared to new construction (Underground Construction
[UC], 2016). New trenchless renewal technologies continue to come to market and improvements in
existing technologies are ongoing. An increased understanding of these new renewal options will
ultimately assist drinking water utilities to optimize their choices for reducing water loss and help
wastewater utilities to optimize their choices for addressing infiltration and inflow issues in a cost-
effective manner. To support information sharing, the U.S. Environmental Protection Agency (EPA)
supported this research effort for the collection of case studies on the use of trenchless pipeline renewal
methods. This task also created a Web-based, searchable database that utility personnel can use to obtain
technology performance and cost data. Several findings are also presented on trends in the water and
wastewater renewal market and opportunities for future technology improvements based on a review of
the case study results.
For water main renewal, 107 case studies were collected. Spray-on lining, cured-in-place pipe (CIPP), and
close-fit lining were identified as the most prevalent methods from the case study collection efforts.
Lessons learned and the needs for future improvements for each of these renewal technologies are
summarized. Overall, the use of water main renewal technologies was highest in the northeast (18%)
followed by the southwest (16%) and north central (16%) U.S. regions. At the same time, a large number
of water main renewal case studies were identified in Canada or outside of North America (29%)
indicating that the use of these technologies may be more prevalent outside the U.S. This suggests there is
room for growth in the U.S. market as the demand for water main renewal services increases over time.
For wastewater main renewal, 82 case studies were collected. CIPP is by far the dominant technology.
The case study results focus on innovations identified in ultraviolet-cured and reinforced CIPP liners,
spiral wound lining, and spray-on lining for sewer mains. After conventional CIPP, these technologies
were identified as the next most prevalent methods used for sewer main renewal from the case study
collection efforts. Lessons learned and the needs for future improvements for each of these technologies
are summarized. The most wastewater main renewal case studies were identified in the north central
region at 25%. This was followed by the northeast (19%) and southwest (19%) regions. In contrast to
water main renewal, only 9% of the case studies identified were located in Canada or outside North
America. This reflects the stronger domestic market for wastewater main renewal due to enhanced
regulatory drivers.
A data mining algorithm was also developed to extract and normalize cost data from the case studies and
to plot the data for ease of review. To serve as a benchmark, bid cost data were collected for conventional
renewal technologies including cement mortar lining (CML) for water mains and sliplining for sewer
mains for comparison to the innovative technology costs. CML and sliplining technologies were chosen
to benchmark costs because of their well-established and long-term history of use nationwide. Costs can
vary widely based on site-specific conditions such as cleaning needs, dewatering needs, the need for night
work to avoid traffic disruption, and other factors. Cost curves are provided in the online tool to view unit
costs from the case studies.
The Web-based, searchable tool created as part of this research project can be used to review: the renewal
technologies used; the conditions under which the technology was implemented; costs; lessons learned;
and utility contact information. Utilities are encouraged to review the case studies for relevance to their
own system and to support future expansion of the online database through the addition of their own case
study information.
IV
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TABLE OF CONTENTS
DISCLAIMER i
ABSTRACT ii
ACKNOWLEDGMENTS iii
EXECUTIVE SUMMARY iv
FIGURES v
TABLES vi
ABBREVIATIONS AND ACRONYMS vii
Section 1.0: INTRODUCTION 1
1.1 Objective of this Study 1
1.2 Study Background 1
1.3 Organization of the Report 1
Section 2.0: DATABASE DEVELOPMENT APPROACH 3
2.1 Database Need and Value 3
2.2 Database Location and Accessibility 3
2.3 Database Overview 3
2.3.1 Login Page 3
2.3.2 Background Pages 3
2.3.3 Methods Page 4
2.3.4 Case Studies 6
2.3.5 RehabAnalytics 8
Section 3.0: WATER MAIN RENEWAL MARKET AND INNOVATIONS 10
3.1 Spray-On Lining for Water Mains Case Study Findings 11
3.2 CIPP for Water Mains Case Study Findings 12
3.3 Close-Fit Lining for Water Mains Case Study Findings 14
3.4 RehabAnalytics Data Review for Water Mains 15
Section 4.0: WASTEWATER MAIN RENEWAL MARKET AND INNOVATIONS 18
4.1 CIPP for Wastewater Mains Case Study Findings 19
4.2 Spiral Wound Linings for Wastewater Mains Case Study Findings 21
4.3 Spray-On Linings for Wastewater Mains Case Study Findings 22
4.4 RehabAnalytics Data Review for Wastewater Mains 24
Section 5.0: CONCLUSIONS 26
Section 6.0: REFERENCES 28
FIGURES
Figure 2-1. Home Page of the Database Web Site 4
Figure 2-2. Wastewater Main Rehabilitation Techniques 5
Figure 2-3. Water Main Rehabilitation Techniques 5
Figure 2-4. Water Main Renewal Case Study Locations 6
Figure 2-5. RehabAnalytics Total Count Summary for Water Main Case Studies 8
Figure 2-6. RehabAnalytics for Water Main Case Studies 9
Figure 2-7. RehabAnalytics Water Main Renewal Comparison Cost Plot 9
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Figure 3-1. Expenditures on Water Pipeline Infrastructure 10
Figure 3-2. Rehabilitation Approaches for Water Mains 10
Figure 3-3. RehabAnalytics Normalized Cost Data for Spray-On Polymeric Lining of Water Mains 16
Figure 3-4. RehabAnalytics Normalized Cost Data for CIPP of Water Mains 16
Figure 3-5. RehabAnalytics Normalized Cost Data for Close-Fit Sliplining of Water Mains 17
Figure 4-1. Expenditures on Wastewater Pipeline Infrastructure 18
Figure 4-2. Rehabilitation Approaches for Wastewater Mains 19
Figure 4-3. RehabAnalytics Total Count Summary for Wastewater Case Studies 24
Figure 4-4. RehabAnalytics Normalized Costs Data for Spiral Wound Lining of Sewer Mains 25
Figure 4-5. RehabAnalytics Normalized Costs Data for Spray-On Lining of Sewer Mains 25
TABLES
Table 2-1. Example Water Main CIPP Case Study 7
Table 3-1. Summary of Spray-on Polymeric Lining Case Studies for Water Mains 11
Table 3-2. Summary of CIPP Case Studies for Water Mains 12
Table 3-3. Summary of Close-Fit Lining Case Studies for Water Mains 14
Table 4-1. Summary of Ultraviolet CIPP Case Studies for Wastewater Mains 20
Table 4-2. Summary of Spiral Wound Lining Case Studies for Wastewater Mains 22
Table 4-3. Summary of Spray-on Lining Case Studies for Wastewater Mains 23
VI
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ABBREVIATIONS AND ACRONYMS
AC
asbestos cement
EPA
U.S. Environmental Protection Agency
CCTV
closed-circuit television
CI
cast iron
CIPP
cured-in-place pipe
CML
cement mortar lining
DI
ductile iron
HDPE
high density polyethylene
PCCP
pre-stressed concrete cylinder pipe
PE
polyethylene
psi
pound per square inch
PVC
polyvinyl chloride
RCP
reinforced concrete pipe
RCCP
reinforced concrete cylinder pipe
SOT
state-of-technology
TO
task order
TTC
Trenchless Technology Center
QA
quality assurance
QC
quality control
UC
Underground Construction
VCP
vitrified clay pipe
WERF
Water Environment Research Foundation
Vll
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Section 1.0: INTRODUCTION
1.1 Objective of this Study
As U.S. utilities continue to shore up their aging water and wastewater infrastructure, renewal needs now
represent over 43% of annual expenditures compared to new construction. Approximately 33% of
projects overall are reported to utilize some form of trenchless technology (Underground Construction
[UC], 2016). New trenchless renewal technologies continue to come to market and improvements in
existing technologies are ongoing. Despite the growing use and acceptance of trenchless technologies
nationwide, many water and wastewater utilities remain unaware of the full range and capabilities of
available technologies. An increased understanding of these renewal options will ultimately assist
drinking water utilities in reducing water loss and help wastewater utilities to address infiltration and
inflow issues in a cost-effective manner. For the purposes of this report, renewal technologies are
considered to cover the repair, rehabilitation, and replacement of pipes via trenchless means (e.g.
excluding open cut approaches). This research effort involved the collection of case studies on the use of
various pipeline renewal methods and provides the information in an online searchable database. The
overall objective was to further support technology transfer and information sharing regarding emerging
and innovative renewal technologies for water and wastewater mains.
1.2 Study Background
Water and wastewater utilities have shown great interest in having access to renewal case study
information. Therefore, this Web-based database fulfills a need in the industry to document and share
lessons learned from real-world projects with varying host pipe and site conditions. The database contains
both quantitative parameters on host pipe condition and technology specifications, along with lessons
learned from technology applications. This research builds upon previous work to document the state-of-
technology for water main renewal (Environmental Protection Agency [EPA], 2013) and wastewater
main renewal (2010), to demonstrate innovative renewal technologies in the field (EPA, 2012a; EPA,
2012b; EPA, 2014a, EPA, 2016a), and to review available technology selection decision-support tools
(EPA, 2011).
Decision support tools do exist for the selection of renewal technologies, but several gaps remain in these
tools (EPA, 2011). These tools are capable of performing critical decision functions (i.e., processing
condition assessment data; screening multiple technologies based on various technical parameters;
performing cost analysis; and ranking applicable technologies). However, most tools lack other crucial
information including: access to more alternative renewal options and data; access to regional cost data;
access to technology case histories, specifically for new methods; and access to utility users that have
used the technology for further information about applicability and lessons learned. Further guidance on
tools used to select renewal technologies is provided in EPA (2011).
This task created a Web-based, searchable tool that utility personnel can use to obtain technology
performance and cost data, as well as case study references. The renewal case studies include:
technologies used; the conditions under which the technology was implemented; costs; lessons learned;
and utility contact information.
1.3 Organization of the Report
The remainder of the report is organized into the following sections:
• Section 2 Database Development Approach. Section 2 describes the development of the
database for storing renewal technology data, its user interface, and data mining approaches.
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• Section 3 Water Main Renewal Market and Innovations. Section 3 describes the current state
of the water main renewal market and recent innovations. Water main renewal case studies are
organized by technology type and cover characteristics related to host pipe types, pipe sizes, and
regional distribution, along with findings on lessons learned.
• Section 4 Wastewater Main Renewal Market and Innovations. Section 4 describes the current
state of the wastewater main renewal market and recent innovations. Wastewater main renewal
case studies are organized by technology type and cover characteristics related to host pipe types,
pipe sizes, and regional distribution, along with findings on lessons learned.
• Section 5 Conclusions. Section 5 provides the conclusions from the current work and
recommendations to further advance the use of innovative and cost-effective renewal
technologies.
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Section 2.0: DATABASE DEVELOPMENT APPROACH
This section describes the overall approach to the online database development and provides an overview
of the features and capabilities of the user interface. The data mining methods deployed to analyze the
renewal case study information are also discussed.
2.1 Database Need and Value
The Web-based renewal technology case study database provides a vehicle to share case studies for
different trenchless technologies installed in locations nationwide. The database contains key technology
parameters, as well as lessons learned from utilities on the installation, quality assurance/quality control
(QA/QC), and operation and maintenance of renewal technologies. The primary focus was on emerging
and innovative renewal technologies suitable for water and wastewater mains from each of the six regions
of the U.S. (i.e., northeast, southeast, north central, south central, northwest, and southwest). Additional
case studies were collected from Canada, Mexico, Europe, and other locations in situations where the
numbers of domestic case studies were limited. More than 180 case studies were identified for water main
and wastewater renewal technologies. The case studies were collected from EPA sponsored field studies,
journal articles, conference proceedings, trade magazines, and vendor-supplied information.
2.2 Database Location and Accessibility
The database is currently being maintained and housed on a server at the Louisiana Tech University
Trenchless Technology Center (TTC). It is accessible through the following Web link:
http://138.47.78.37/Retrospective. The database is available online through a Web site constructed using
Microsoft ASP.Net technology with C#.Net and the database software is MySQL.
2.3 Database Overview
2.3.1 Login Page. The Login page requires the following account information: username, password,
and role. Two roles are specified in the dropdown menu including User and Administration. For the first
time user, there is an option to register and the administrator is alerted by an e-mail notification to
authorize access. An e-mail will then follow from the administrator to the new user once the request for
an account has been approved. Once logged in, the user can access the Web pages and RehabAnalytics
tool described below. The Web site is a free database with no charge to access the content, but an account
is requested for security and access purposes.
2.3.2 Background Pages. After successful login, the user is directed to the Home page where a brief
description of the project is given. As shown in Figure 2-1, the Web site housing the database consists of
the following Web pages:
• Home Page,
• Research Page,
• Team Page,
• Methods Page,
• Case Studies Page,
• RehabAnalytics,
• Submit, and
• Account Profile/Login.
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Trenchless Technology Center
Louisiana Tech University
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Tins Web site serves as a readily accessible tool for stakeholders to share their experience and data on long-term trenchless technology performance for water
distribution and wastewater collection systems. The main component of this project has been a retrospective evaluation of the long-term performance of wastewater
technologies now that some have been installed for more than half of their target life cycle. In addition, the use of trenchless technologies for wastewater and water main
renewal is growing and another component of this project included the collection of case studies to document their use nationwide.
Disclaimer: This database has been subjected io the Agency's peer and administrative reviews and lias been approved for publication. Am' opinions expressed are those of the
authors and do not necessarily reflect the views of the Agency; therefore, no official endorsement should be infeired. Any mention of trade names or commercial products
does not constitute endorsement or recommendation for use.
Trenchless rehabilitation technologies have been steadily increasing in use over the past 30 years and represent an increasing proportion of the annual operation and
maintenance expenditures for the nation's water and wastewater infrastructure. Despite public investment in use of these technologies, there has been little quantitative
evaluation of how these technologies are performing over the long-term. The goal of the U.S. Environmental Protection Agency (EPA) retrospective evaluation research is
to provide improved information to utilities on the life-cycle performance of various rehabilitation technologies.
Figure 2-1. Home Page of the Database Web Site
Under the Research Web page, the overall research objectives are explained, along with information
about the database. This Web site houses both a wastewater retrospective case study database (EPA,
2014b) and the renewal case study database described in this report. The Web site describes the objectives
for both research efforts. The retrospective case study database was focused on the collection of case
study information from trenchless projects that had been installed decades ago, along with physical pipe
specimens to assess the long-term performance of well-established trenchless technologies. The renewal
case study database was focused on the collection of case study information with a primary focus on more
recent emerging and innovative trenchless technology applications. The participants on the research team
from Battelle and TTC are presented under the Team Web page, along with acknowledgments.
2.3.3 Methods Page. Separate tabs for Wastewater and Water technologies are provided under the
Methods Web page (see Figures 2-2 and 2-3). The main focus of the database is on the rehabilitation
methods listed below, although spot repair case studies are also addressed in the renewal database. Under
the Wastewater tab, various sewer main rehabilitation methods are outlined that are included as part of the
database structure. Under the Water tab, various water main rehabilitation methods are outlined that are
included as part of the database structure. This serves as a reference for the general categories of available
technologies and links are provided to the relevant state-of-technology (SOT) reports for more detailed
information (EPA, 2013; EPA, 2010).
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Trenchlcss Technology Center
Louisiana Tech University
£EPA
Batreiie
Home Research Team
Methods
Case Studies RehabAnalytics Submit Profile H Logout
Wastewater
Trenchless rehabilitation methods applied to sewer mainlines include the use of CIPP, close-fit linings, sliplining, grout-in-place: spiral-wound linings, panel linings, spray-
on spin-cast linings, and chemical grouting. Further information on various repair, replacement, and rehabilitation technologies for wastewater collection systems can be
found in the U.S. EPA report titled State of Technology for Rehabilitation of Wastewater Collection Systems.
SUMMARY OF WASTEWATER REHABILITATION TECHNIQUES
Rehabilitation Technique
CIPP
Close Fit
Sliplining
Grout-in-place
Spiral Wound
Panel Linings
Spray/Spincast
Grouting
• Thermal Cure
• UV Cure
• Unreinforced
¦ Reinforced
• Hybrid
• Fold-and-Form
• Deform & Reform
• Symmetrical/Reduction
• Symmetrical
Compression
• Symmetrical Expansion
• Large Diameter
• Small Diameter
• Preformed
Shapes
• Spiral Wound
• Circular
• Non Circular
• Full Ring
• Partial Ring
• Cementitious
• Epoxy
• Polyurethane
• Polyurea
• Test and
Seal
• Flood
Grouting
Copyright Louisiana Tech University
Figure 2-2. Wastewater Main Rehabilitation Techniques
Trenchless Technology Center
Louisiana Tech University
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Wastewater
Trenchless rehabilitation methods for water mains include the use of spray-on lining, shplining, CIPP, inserted hose lining, and close-fit lining systems. Further information
on various repair, rehabilitation, and replacement technologies for water mains can be found in the U.S. EPA report titled State of Technology for Rehabilitation of Water
Distribution Systems.
SUMMARY OF WATER REHABILITATION TECHNIQUES
Rehabilitation Technique
Cleaning
Spray-On Lining
Sliplining
CIPP
Inserted Hose Lining
Close-Fit Lining
Figure 2-3. Water Main Rehabilitation Techniques
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2.3.4 Case Studies. This page has three subtabs including Wastewater (Retro), Wastewater, and Water.
The Wastewater (Retro) tab provides access to the retrospective rehabilitation technology performance
information collected as part of a companion study to this research effort as documented in EPA (2014b).
The information provided in the retrospective portion of the Web site is described in detail in EPA
(2014b). Under the Wastewater and Water tabs, the renewal case studies of conventional, innovative, and
emerging technologies collected as part of the current research effort can be accessed. The case studies
are searchable through either a dropdown menu of key parameters and/or an interactive map. The Water
tab is shown here as an example in Figure 2-4. The Wastewater tab contains similar information with the
dropdown menu choices tailored to that specific application. Case studies are searchable by: region,
renewal method, pipe material, and pipe diameter. The user can also select "all" in each dropdown box to
view the complete contents of the case study database. Upon selection of the search criteria, the user can
download the case study information into a Microsoft® Excel database that can be viewed online or saved
to their desktop. An example case study for a water main cured-in-place pipe (CIPP) study is provided in
Table 2-1 to illustrate the nature of the information collected. The data collected include utility
information, host pipe information, technology application information, cost, lessons learned, and
references for more details.
U Home
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SELECT A TECHNOLOGY FOR MORE INFORMATION
Select Parameters
Select Region
| All Reg ans
Pipe Material
Select Method
| All Methods
All Materiais
Pipe Diameter
| All D,aiT,-gtfrr5
Down load Excel Report
SUMMARY OF U.S. EPA RENEWAL CASE STUDY LOCATIONS (WATER)
Baitelie
Figure 2-4. Water Main Renewal Case Study Locations
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Table 2-1. Example Water Main CIPP Case Study
Utility Information
Agency
City of Cleveland Water Division, Cleveland, OH
Region
North Central
Primary Contact
Greg Sattler, Water Utility Technical Lead, (216) 664-2444,
gregory_sattler(S?clevelandwater.com
System Type
Water Distribution
System Size
5,200 miles of water mains
Host Pipe Data
Host Pipe Location
Femcliffe Avenue between West 190th and Rock River Drive, Cleveland, OH
Host Pipe Installation Date
1914 and 1949
Host Pipe Material
Cast Iron (CI)
Host Pipe Shape
Circular
Host Pipe Diameter (in)
6
Host Pipe Length
1,996 ft Long
Host Pipe Burial Depth and Water Table
6 ft Deep Pipe; Groundwater Table Below the Pipe
Condition Assessment History
CCTV Inspection Prior to Lining
Problem in the Host Pipe
Cracking, Corrosion, Debris, Tuberculation
Technology Data
Technology Type
Cured-in-Place Pipe (CIPP)
Technology Name
Sanexen Aqua-Pipe®
Date Installed
September 10-18,2010
Technology Design
2.5 mm Liner Thickness per ASTM F1216
Technology Installer/Vendor
Terrace Construction/Sanexen
Cleaning Method Used
Hydraulic Jet Cleaning, Scraping, and Swabbing
Technology QA/QC Data
Post-Lining CCTV, Lining Thickness, Flow Test, Pressure Testing, and Structural
Material Testing
Cost Data ($/LF)
$187.38
Cost Notes
Lining Cost Only
Lessons Learned
Construction Problems
Had to reinstate 27% of the services externally, which is well above the typically
reported 5-10%
Technology Performance Problems
None reported
Adjustments Made
N/A
Continued Use of the Technology
Multiple utilities have expressed their willingness to use this technology again
Reference
EPA. (2012). Performance Evaluation of Innovative Water Main Rehabilitation CIPP
Lining Product in Cleveland, OH. EPA/600/R-12/012, U.S. EPA, ORD, NRMRL,
Edison, N.T, Feb., 117 pp.
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2.3.5 RehabAnalytics. Data analytics provides a powerful tool for the automated analysis and
correlation of datasets. The RehabAnalytics tool was created by TTC using Visual Studio 2010 to provide
data mining and Web-based data analyses for the renewal case studies. Trends are analyzed and displayed
based upon the frequency of use of renewal technologies nationwide. Cost data curves were also
incorporated based on bid cost data analyses for various innovative and conventional renewal
technologies. The RehabAnalytics Web page allows access to this data mining component to
automatically query and display aggregated data and trends across multiple case study sites from the
database.
RehabAnalytics displays case study frequency counts and cost data plots for wastewater and water main
renewal technologies. For example, the Frequency Plot subtab under the Water tab runs a query to display
the total number of case studies by water main renewal method (see Figure 2-5). A similar plot is
available online for the wastewater main renewal case studies. This plot is actively generated from the
database, so it has the ability to automatically update as new case studies are added.
Frequency Plot
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Figure 2-5. RehabAnalytics Total Count Summary for Water Main Case Studies
RehabAnalytics also provides a feature to retrieve unit cost data from the case studies and compare them
to bid costs for conventional renewal technologies. Hie major cost components are also summarized in
the case studies under "cost notes" to describe what cost factors are included or excluded from the cost
estimate. The Cost Plot subtab is shown in Figure 2-6 for the water main case studies where the user can
select the renewal method of interest from the dropdown box. An example plot is provided in Figure 2-7
of unit water main CIPP costs versus conventional cement mortar lining (CML) costs as normalized by
diameter. This plot is provided to benchmark the unit costs versus a conventional technology that is
familiar to water utilities. A curve fitting function is also provided.
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Select Method
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I Spray-on Polymeric Lining,'"Coating
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Figure 2-6. RehabAnalytics for Water Main Case Studies
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Section 3.0: WATER MAIN RENEWAL MARKET AND INNOVATIONS
The adoption of trenchless technologies for potable water applications has been slower than wastewater
applications, but it is becoming more prevalent over time. Over the past 18 years, total U.S. municipal
spending on drinking water distribution systems has more than doubled from $2.6 to $6.3 billion (see
Figure 3-1). In that same timeframe, the expenditures on water main renewal has more than tripled from
$0.6 billion in 1998 to $2.2 billion in 2016. Water main renewal is also a growing proportion of the total
expenditures compared to new construction, reaching 35% in 2016 (UC, 2016). This section reviews the
overall status of the water main renewal market based on the collected case studies and relevant industry
information. Available water main renewal technologies are presented, along with a summary- of the case
studies identified including total case study counts, pipe sizes, pipe material types, regional distribution,
and any findings on lessons learned. The technologies are categorized as shown in Figure 3-2 with a focus
on spray-on linings, CIPP, and close-fit lining, which were identified as the most prevalent methods used
for water main renewal from the case study review.
$7
$6
$5
$4
$3
$2
$1
$0
r& <$>
^ jv> «s?
\v C\> C^v <\> C\v <\> Pv>
¦ Water (New) ¦ Water (Rehab)
SOURCE: UCT Magazine 19th Annual Municipal Survey
Figure 3-1. Expenditures on Water Pipeline Infrastructure (UC, 1998 to UC, 2016)
Rehabilitation
Cleaning
Spray-On
Lining
Sliplining
][
]
CIPP
]
Inserted
Hose Lining
Close-Fit
Lining
Figure 3-2. Rehabilitation Approaches for Water Mains (EPA, 2013)
10
-------
3.1 Spray-On Lining for Water Mains Case Study Findings
Spray-on linings include either cementitious or polymer-based linings. They can be applied using
conventional spray applications or spin-cast, projectile, or centrifugal applications. CML has been widely
used for water main rehabilitation when corrosion protection of the interior surface is needed. Because the
use of CML for water mains is well established, it is not further addressed in this report. The report does
address a growing trend in the use of innovative polymeric linings that have been designed to provide for
structural rehabilitation in addition to corrosion protection. More detailed information on spray-on linings
can be found in Ellison et al. (2010). Over 19 spray-on lining products have been NSF 61 approved as
coatings suitable for potable water main rehabilitation. Table 3-1 summarizes the 27 spray-on polymeric
lining case studies for water mains identified as part of the case study collection efforts.
Table 3-1. Summary of Spray-on Polymeric Lining Case Studies for Water Mains
Company Information
i
Case Study
Information
Vendor
Technology
Name
Headquarters
Location
Annual
Sales
($M)
BySl
No.
of
Case
Studies
¦
Pipe
Size
Range
(in)
Pipe
Materials
3M
Scotchkote™
Pipe Renewal
Liner 2400
St. Paul, MN
$31,821
89,800
5
NE, CA,
NNA
6 -10
CI
Acuro
Polymeric Resin
Lining
Montreal,
Quebec,
Canada
NA
NA
9
CA
4 -10
CI, DI
Nu Flow
Epoxy Coating
Osliawa,
Ontario,
Canada
$2.9
31
8
NE, SE,
NNA
1 -4
CU
Quest Inspar
Pipe Armor 150S
W
Kent, WA
$8.8
46
1
NW
58
SP
Radius
Systems
(Subterra)
Fast-Line Plus™
Polyurethane
Lining
Alfrcton.
Derbyshire,
England
$106
449
3
NNA
6-32
CI
Warren
Environmental
Epoxy and
Pressure Infusion
Lining System
Middleboro,
MA
$2.9
8
1
SW
42
PCCP
Note:
Regions: NE (North East). SE (South East). NC (North Central). SC (South Central). NW (North West). SW (South West). CA (Canada). NNA
(Non-North America)
Pipe Materials: CI (Cast Iron), CIL (Cast Iron, Lined), DI (Ductile Iron), DIL (Ductile Iron, Lined), SP (Steel Pipe), SPL (Steel Pipe, Lined),
PVC (Polyvinyl Chloride), HDPE (High-Density Polyethylene), PCCP (Prestressed Concrete Cylinder Pipe), RCP (Reinforced Concrete Pipe),
AC (Asbestos Cement), CLT (Copper Pipe), RCCP (Reinforced Concrete Cylinder Pipe), LI (LTnknowti)
The majority of case studies identified were located in Canada and Europe suggesting that there is still
room for additional growth in the application of spray-on lining technologies within the U.S. Water main
pipe sizes requiring renewal ranged from 4 to 58 inches with the host pipes consisting primarily of ferrous
pipes, but also steel and pre-stressed concrete cylinder pipe (PCCP). The host pipe condition issues
addressed included reduced structural integrity, breaks, leaking joints, tuberculation, corrosion, discolored
water, low flow, and low pressure. One technology (Nu Flow) was applied primarily for copper service
lines ranging in size from 1 to 4 inches to address pinhole leaks and discolored water. One hybrid
technology was installed on a 42-inch water main in Mesa, Arizona that combined a spray-applied epoxy
from Warren Environmental with a carbon fiber lining to provide for an innovative structural repair.
11
-------
No major issues were noted with spray-on lining products available on the market. Surface preparation is
an important first step in the spray-on lining process and a variety of cleaning methods were used
including abrasive blasting, rack-feed boring, scraping, and water jetting. The types of QA/QC activities
included post-lining closed-circuit television (CCTV), lining thickness verification, hydraulic pressure
testing, and flow tests. One large-scale installation with a man-entry pipe (58 inches in diameter) included
visual inspection for QA/QC. Across the case studies, minor construction issues were noted with blisters,
small areas of lining discontinuity at joints, and some equipment downtime (e.g., liner gun and thickness
gauge). Future technology refinement is needed to ensure minimum thicknesses are met in a consistent
manner throughout the installation. Thickness verification is suggested as a QA/QC measure for all
installations and a standardized approach to post-lining QA/QC processes could be adopted for spray-on
applications. The consistent application of spray-on linings is an important issue for further research.
3.2 CIPP for Water Mains Case Study Findings
CIPP lining involves the insertion of a resin-saturated tube into the host pipe. The tube is first placed by
air or water inversion (or a winch) and then expanded against the host pipe using air or water pressure.
The resin is cured using steam or hot water to form a structurally sound pipe liner within the deteriorated
host pipe. A recent innovation is an ultraviolet-cured application suitable for water mains (SAERTEX-
Liner® H20). For potable water main applications, the resins are certified as safe for use through NSF 61.
Currently, ten CIPP products are certified for water main rehabilitation within the U.S. Of these 10 CIPP
products, two are steam cured, one is ultraviolet-cured, and the remaining seven are hot water cured. Most
require an additional ambient cure time ranging from 2 to 7 days before returning to service. More
information on CIPP for water mains can be found in EPA (2013). Table 3-2 summarizes the 32 CIPP
case studies for water mains identified as part of the case study collection efforts.
Table 3-2. Summary of CIPP Case Studies for Water Mains
Company Information
Case Study
Information
Vendor
Technology
Name
Headquarters
Location
Annual
Sales
($M)
H
No. of
Case
Studies
¦
Pipe Size
Range
(in)
Pipe
Materials
Ashimori
PALTEM
Osaka, Japan
$453.5
2,146
1
NNA
32
DIL
Insituform
InsituMain®
CIPP Lining
Chesterfield,
MO
$276.9
3,280
7
NC, SC,
SW
10-24
CI, DI, DIL,
SP,SPL
Insituform
PPL® CIPP
Lining
Chesterfield,
MO
$276.9
3,280
1
SW
27
SP
Karl Weiss
Technologies
Starline
HPL-W
Berlin
Germany
$22.9
185
1
NNA
20
CI
LiquiForce
CIPP
Kingsville,
Ontario,
Canada
$2.8
45
2
NC, CA
12-48
CI,U
Sekisui
Norditube,
Inc.
NordiPipe™
CIPP Lining
San Clemente,
CA
$0.5
5
5
NE, NW,
NNA
12-36
AC, CI, DI,
SP
Sanexen
Aqua-Pipe®
CIPP Lining
Brossard,
Quebec,
Canada
$112.2
240
15
NE, NC,
SE, SW,
CA
6-12
AC, CI, DI
Note:
Regions: NE (North East). SE (South East). NC (North Central). SC (South Central). NW (North West). SW (South West). CA (Canada). NNA
(Non-North America)
Pipe Materials: CI (Cast Iron), CIL (Cast Iron, Lined), DI (Ductile Iron), DIL (Ductile Iron, Lined), SP (Steel Pipe), SPL (Steel Pipe, Lined),
PVC (Polyvinyl Chloride), HDPE (High-Density Polyethylene), PCCP (Prestressed Concrete Cylinder Pipe), RCP (Reinforced Concrete Pipe),
AC (Asbestos Cement), CU (Copper Pipe), RCCP (Reinforced Concrete Cylinder Pipe), LI (Unknown)
12
-------
The majority of the case studies identified were located within the north central U.S. likely due to their
proximity to the main C1PP vendors for water main applications. Water main pipe sizes requiring renewal
ranged from 6 to 48 inches with the host pipes consisting of asbestos cement (AC), cast iron (CI), ductile
iron (DI), and steel pipe types. The host pipe condition issues addressed included large cracks, joint leaks,
known leaks identified from pipe inspections, construction damage, and external corrosion. It was noted
that many of the CIPP installations for water mains were located in high consequence areas such as under
highways, railways, airport facilities, water treatment plant facilities, schools, and congested downtown
locations (e.g., Madison Avenue in New York City). This suggests that CIPP may be selected at
challenging sites where there is a high need for improving structural integrity through use of a technology
with an established track record.
Across the CIPP case studies, no major issues were noted with products available on the market. QA/QC
measures included hydraulic pressure testing, liner thickness measurements, mechanical testing, and post-
lining CCTV inspection. Some challenging site-specific conditions were noted such as a congested
subsurface that limited pit excavation locations and challenges related to bends in pipelines. For example,
the CIPP at one location could only be rated for 30 pounds per square inch (psi) versus the 50 psi design
because of an unanticipated 45 degree bend. The installation was still accepted by the owner as the water
distribution system operating pressure was around 15 psi at that location . Minor construction issues were
noted with the need to reinstate service lines manually through excavation for a higher percentage of
locations than expected at 20%, 27%, and 89% for three case studies. Future technology refinement may
be needed to improve the ability to reconnect service lines without the need for excavations. A case study
from an EPA field demonstration project of an innovative CIPP rehabilitation of a water main is
highlighted below (EPA, 2012b).
INNOVATIVE CIPP PRODUCT FOR WATER MAINS IN CLEVELAND, OHIO
Under a related research effort, EPA performed an evaluation of an
innovative CIPP lining product for water main rehabilitation in Cleveland,
Ohio. The project evaluated the technology maturity, feasibility,
complexity, performance, cost, and environmental impact. This case study
is included in the Web-based renewal database (see Table 2-1). The full
results are reported in EPA (2012b) for more information.
The field demonstration of the Sanexen Aqua-Pipe® CIPP liner in
Cleveland provided valuable information on the design, installation, and
QA/QC of CIPP used to rehabilitate water mains. The field demonstration
involved the CIPP lining of approximately 2,000 ft of a 6-mch cast iron
water main pipeline that had been installed in 1914 and 1949. The testing
results showed that the CIPP as installed exceeded the applicable
requirements of ASTM F-1216 to provide for a Class IV fully-structural
liner. Findings from the study included the need to improve the cleaning
process in order to avoid damaging or deforming corporation stops and to
address other issues contributing to the need to excavate and externally
reinstate 17 of the 63 service connections (27%). A more typical external
reinstatement rate was reported to be 5% to 10% by the vendor (EPA,
2012b). Case study results from the water main renewal database suggest
that fully internal reinstatement of service lines can be a challenge for
several water main CIPP technologies depending on site conditions.
13
-------
3.3 Close-Fit Lining for Water Mains Case Study Findings
Close-fit lining involves the use of a thermoplastic liner for insertion into a deteriorated host pipe. The
liner materials typically consist of polyethylene (PE) or polyvinyl chloride (PVC). The thermoplastic liner
is temporarily deformed to reduce its cross section before insertion. The liner can be deformed either in
the field or at the manufacturer's facility. Once the liner shape is restored, it forms a close-fit within the
host pipe. The close-fit lining technique helps to overcome issues caused by conventional sliplining,
which can result in a significant reduction in the pipe cross section and a large annular space between the
liner and host pipe that must be grouted. A close-fit liner can serve as a semi-structural solution for
spanning holes and gaps or as a fully structural liner depending upon its standard dimension ratio and the
operating pressure of the host pipe (EPA, 2013). Table 3-3 summarizes the 42 close-fit lining case studies
for water mains identified as part of the case study collection efforts.
Table 3-3. Summary of Close-Fit Lining Case Studies for Water Mains
Company Information
Case Study Information
Vendor
Technology
Name
Headquarters
Location
Annual
Sales
($M)
No. of
Case
Studies
Regions
Pipe
Size
Range
(in)
Pipe
Materials
Insituform
InsituGuard®
Close-Fit
Lining
Chesterfield,
MO
$276.9
3,280
1
NE
48
CI
Insituform
Thermopipe®
Chesterfield,
MO
$276.9
3,280
5
SW,
NNA
6-12
AC, CI,
SP
Radius
Systems
(Subterra)
PE Structural
(Rolldown
Process)
Alfreton
Derbyshire,
England
$106.2
449
1
NNA
12
CI
Radius
Systems
(Subterra)
Subcoil
Polyethylene
Liner
Alfreton
Derbyshire,
England
$106.2
449
2
NNA
9-42
CI, RCP
Radius
Systems
(Subterra)
Subline Fold
and Form
Alfreton
Derbyshire,
England
$106.2
449
6
NE,
NNA
30-59
CI, PCCP
Swagelining
Reduced
Diameter
Pipe
Clydebank,
Dunbartonshire,
Scotland
NA
4
12
SC,
SW,
NNA
16-39
CI, SP,
SPL,
PCCP,
RCP,
RCCP
Underground
Solutions,
Inc.
Duraliner™
Poway, CA
$6.9
49
6
NE,
NC, SE
6-20
AC, CI,
DI
Underground
Solutions,
Inc.
Fusible PVC
Continuous
Sliplining
Poway, CA
$6.9
49
9
NC,
NE,
NW,
SE, SW,
SC
6-36
CI, DI,
SP, SPL,
HDPE
Note:
Regions: NE (North East). SE (South East). NC (North Central). SC (South Central). NW (North West). SW (South West). CA (Canada). NNA
(Non-North America)
Pipe Materials: CI (Cast Iron), CIL (Cast Iron, Lined), DI (Ductile Iron), DIL (Ductile Iron, Lined), SP (Steel Pipe), SPL (Steel Pipe, Lined),
PVC (Polyvinyl Chloride), HDPE (High-Density Polyethylene), PCCP (Prestressed Concrete Cylinder Pipe), RCP (Reinforced Concrete Pipe),
AC (Asbestos Cement), CU (Copper Pipe), RCCP (Reinforced Concrete Cylinder Pipe), LI (Unknown)
14
-------
Most of the close-fit lining case studies identified were located within the northeastern and southwestern
U.S. Water main pipe sizes requiring renewal ranged from 6 to 59 inches with the host pipes consisting of
AC, CI, DI, steel pipe types, along with reinforced concrete pipe (RCP), reinforced concrete cylinder pipe
(RCCP), and PCCP. The host pipe condition issues addressed included breaks, leaks, leaking joint seals,
tuberculation, discolored water, root ingress, internal pitting, and external corrosion. Other mechanical
issues with the host pipes included pipe displacement under a river bed, deflected joints, leaks from
gasket failures, and the corrosion of bolts holding mechanical joints together. Site considerations that
drove the need for renewal by close-fit lining included the weight of a highway expansion, redevelopment
of the area requiring renewal, and the conversion of a sewer pipe into a water transmission main.
Across the close-fit lining case studies, no major issues were noted with products available on the market.
QA/QC measures included primarily post-lining hydraulic pressure testing at pressures ranging from 150
to 200 psi. Some challenging site-specific conditions were noted such as root ingress causing the need for
manual cutting of root masses in the host pipe to facilitate the close-fit lining insertion. Minor
construction issues were noted including issues with the deformation process, pipe breakage, and pull
head. Due to extreme cold at one site, the high density polyethylene (HDPE) pipe had to be warmed up to
room temperature prior to being reduced. This same site experienced a few weld breaks while pulling in
the close-fit liner and the exact cause of the breakages was not determined. At another site one pipe break
occurred after pulling 210 meters, which was caused by the lack of coherence of the weld. Two sites
noted issues with the pull head. At one site, the pull head broke away from the pipe string during the
initial pulling activities. A different pull head was brought to the site and fused to the pipe string and no
other issues were encountered. At another site it was found that a longer pull head was needed to prevent
breaking the pipe. Another issue noted in the technology selection considerations was the need for custom
made connections from HDPE to steel pipe.
3.4 RehabAnalytics Data Review for Water Mains
The RehabAnalytics page contains summary information on case studies for water main renewal
including total case study counts (see Section 2, Figure 2-5) and an automated plotting of normalized cost
data. The largest number of case studies collected was for close-fit lining (42), followed by CIPP (32),
and spray-on polymeric lining (27). Bid cost data were also collected for water main renewal by CML to
benchmark the innovative technology costs. Although it is not a structural repair, CML is a widely-used
renewal method and utilities will be familiar with typical costs for their region for this conventional
technology. The trenchless technology cost data collected were normalized to the host pipe footage and
diameter for the project as shown in Figures 3-3 to 3-5 for spray-on polymeric lining, CIPP, and close-fit
lining, respectively, for water mains. The spray-on polymeric lining normalized costs for water mains
ranged from $3 to $35 per linear foot per inch diameter (Figure 3-3). Ellison et al. (2010) has suggested
that detailed pipe wall inspections could save costs for spray-on lining applications by lining only where
it is needed at the appropriate thickness (e.g., for non-, semi-, full-structural applications). However, this
is an area of future research. The CIPP normalized costs for water mains ranged from approximately $10
to $45 per linear foot per inch diameter (Figure 3-4). The close-fit lining normalized costs for water mains
ranged from $3 to $21 per linear foot per inch diameter (Figure 3-5). In the future, the use of trenchless
water main renewal techniques could grow as they become more cost competitive with open trench
replacement and as the capabilities to internally re-connect service lines improves.
15
-------
Spray-on Polymeric Lining/Coating
40
35
Q 30
I
c
2 25
§
CO 20
ix
§ 15
o
|! 10
5
0
o
o
o
o
o
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o
o
o
o
I
\
a
.
o
11
n
1
0
> 0 o
°
8
o CementMortar Lining
^ Spray-on Polymeric Lining/Coating
10 20 30 40
Diameterfln.)
50
60
Figure 3-3. RehabAnalytics Normalized Cost Data for Spray-On Polymeric Lining of Water Mains
Cured-in-Place Pipe (CIPP)
.53
Q
¦
c
l£
§
p
tn
o
O
¦ts
5
50
45
40
35-
30-
25
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Ills. T 8 9
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<0> Cured-in-Place Pipe (CIPP)
10 20 30 40
Diameterfin.)
50
60
Figure 3-4. RehabAnalytics Normalized Cost Data for CIPP of Water Mains
16
-------
Close-Fit Sliplining
Q
c
£
<0
O
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¦t!
5
22'
2'
1
16
14
12
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Figure 3-5. RehabAnalytics Normalized Cost Data for Close-Fit Sliplining of Water Mains
17
-------
Section 4.0: WASTEWATER MAIN RENEWAL MARKET AND INNOVATIONS
A survey recently released by EPA indicates that over $271 billion in total funding is required to address
aging infrastructure needs at publically-owned wastewater utilities (EPA, 2016b). Approximately 53% of
this funding is needed to correct issues with wastewater collection systems including $51.2 billion for
sewer main renewal, $44.5 billion for new sewer main installation, and $48 billion to correct combined
sewer overflow conditions (EPA, 2016b). As shown in Figure 4-1. the annual municipal expenditures on
wastewater main renewal is more than double that for water mains (e.g., at $5 billion versus $2.2 billion
as of 2016). Sewer main renewal is also approximately on par with new sewer main construction at 48%
of the total expenditures with an increasing trend over time (UC, 2016).
$12
CO
c
l/l
w
o
o
i/i
z>
$10
$8
$6
$4
$2
$0
oov£>r-.oocnOT-Hr>4m'3-u"s<£i
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CTjCTiOOOOOOOOOOOOOOOOO
HH(N(SIN(N(NNN(NN(NN(NIN(N(NfMIN
¦ Sewer (New) ¦ Sewer (Rehab)
SOURCE: UCT Magazine 19th Annual Municipal Survey
Figure 4-1. Expenditures on Wastewater Pipeline Infrastructure (UC, 1998 to UC, 2016)
This section reviews the overall status of the wastewater main renewal market based on the collected case
studies and relevant industry information. Available wastewater main renewal technologies are presented,
along with a summary of the case studies identified including total case study counts, pipe sizes, pipe
material types, regional distribution, and any findings on lessons learned. CIPP is by far the dominant
trenchless technology used in wastewater rehabilitation applications. For this reason, this report is focused
on the use of more recent innovations to CIPP including ultraviolet-cured CIPP and glass fiber reinforced
CIPP liners suitable for larger diameter sewer mains. The renewal database also does not focus on pipe
replacement methods such as pipe bursting, but does include several trenchless repair and rehabilitation
technologies. The rehabilitation technologies for wastewater mains are categorized in the database as
shown in Figure 4-2. The discussion in this section is focused on case study results from ultraviolet-cured
and glass fiber reinforced CIPP liners, spiral wound, and spray-on linings for sewer mains. After
conventional CIPP which is a well-established technology, these technologies were identified as the next
most prevalent methods used for sewer main renewal from the case study collection efforts.
18
-------
Grouting
CIPP
Symmetrical
Compression
Flood Grouting
Partial
Symmetrical
Reduction
Polyurethane
Polyurea
Full Ring
Test and Seal
UV Cure
Cementitious
Circular
Hybrid
Thermal Cure
Spiral Wound
Epoxy
Rehabilitation
Reinforced
Figure 4-2. Rehabiiitation Approaches for Wastewater Mains (EPA, 2010)
4.1 CIPP for Wastewater Mains Case Study Findings
Conventional CIPP technologies dominate today's wastewater main renewal market, but innovations are
still ongoing. CIPP technologies can vary based upon tube construction, method of installation, curing
method, and type of resin. After the original CIPP patent expired, a number of new technology variations
came to market for wastewater main rehabilitation. However, most were still similar to the original CIPP
product of a needled felt tube saturated with a polyester resin and cured using hot water or steam (EPA,
2010). Under a related research effort, a comprehensive study was undertaken of the long-term
performance of conventional CIPP for wastewater main rehabilitation. The retrospective study concluded
that CIPP liners with up to 34 years in service showed little evidence of deterioration and that properly
designed and installed CIPP liners should meet and likely exceed the typical 50-year expected design life
(EPA, 2014b). These 25 conventional CIPP case studies are available in the online database. This report
focuses on a review of the case studies involving CIPP innovations including the growing use of
ultraviolet-cured CIPP (as shown in Table 4-1) and glass fiber reinforced CIPP liners developed for larger
diameter sewer mains.
Ultraviolet cured liners were first developed in Germany and began to be promoted more widely for use
worldwide in the 2000s. Several vendors now offer ultraviolet-cured CIPP products within the U.S.
Ultraviolet-cured CIPP involves the use of a glass fiber or polyester fiber tube that is impregnated with
polyester or vinylester resin. The resin-saturated liner is pulled into place by a winch and then the tube is
inflated against the host pipe using compressed air. Curing is then accomplished with an ultraviolet light
train. The liner typically has an inner film and outer film used to contain the resin prior to curing. The
inner film allows for the passage of ultraviolet light and is removed after curing is accomplished. The
outer film is resistant to ultraviolet light and prevents the resin from entering cracks or service laterals.
Among the advantages of ultraviolet-cured CIPP include the minimization of styrene emissions and
process wastewater that are generated from steam or hot water curing (EPA, 2010). As shown in Table 4-
1, five different vendors were identified with 15 ultraviolet-cured CIPP case studies. All of the U.S.
installations occurred relatively recently from 2008 to 2014.
19
-------
Table 4-1. Summary of Ultraviolet CIPP Case Studies for Wastewater Mains
Company Information
Case Study Information
Vendor
Technology
Name
Headquarters
Location
Annual
Sales
($M)
No.
of
Staff
No. of
Case
Studies
Regions
Pipe
Size
Range
(in)
Pipe
Materials
AOC/Insituform
CIPP with
Vipel®
Isophthalic
Polyester
Guelph,
Ontario,
Canada
$10.73
95
3
NC
8-24
Concrete,
VCP
BKP Berolina
Berolina-
Liner®
Velten,
Germany
$6.77
59
1
NNA
12
Concrete
Reline America
Blue-Tek™
Saltville, VA
$8.72
32
6
NE, SC
8-10
VCP
Saertex
Saertex-
Liner®
Saerbeck,
Nordrhein-
Westfalen
Germany
$229.1
1,200
1
SW
6
CI
LightStream LP
Streamliner
UV™
La Jolla, CA
$0,420
4
4
SW
6-18
AC
Note:
Regions: NE (North East). SE (South East). NC (North Central). SC (South Central). NW (North West). SW (South West). CA (Canada). NNA
(Non-North America)
Pipe Materials: Brick. Vitrified Clay Pipe (VCP). Concrete. Prestressed Concrete Cylinder Pipe (PCCP). Reinforced Concrete Pipe (RCP).
Ductile Iron (DI). Steel. Polyvinyl Chloride (PVC). Polyethylene (PE). Fiberglass Reinforced Plastic Pipe (FRP). Unknown (U). Cast Iron (CI).
Asbestos Cement (AC)
The majority of the ultraviolet-cured case studies identified were located within the northeastern and
southwestern U.S. Wastewater main pipe sizes requiring renewal ranged from 6 to 24 inches with the host
pipes consisting of AC, concrete, CI, and vitrified clay pipe (VCP). The host pipe condition issues
addressed included cracks, collapsed sections, root damage, heavy tuberculation, deteriorated o-rings on
VCP, and hydrogen sulfide corrosion on AC pipe. At one site, the ultraviolet-cured CIPP method was
selected to minimize emissions and odor from the resin curing because the project was located in tunnels
beneath an airport terminal.
Across the ultra-violet cured CIPP case studies, no major issues were noted with products available on the
market. There is no current ASTM design standard specific to ultraviolet-cured CIPP. Instead, the design
standard relied upon is ASTM F1216 (2009) Standard Practice for Rehabilitation of Existing Pipelines
and Conduits by the Inversion and Curing of a Resin-Impregnated Tube. QA/QC measures may include
hydraulic pressure testing, lining thickness measurement by calipers, tensile strength (ASTM D638),
flexural strength and modulus (ASTM D790), and a post-lining CCTV inspection. In addition, curing
parameters such as temperature and duration of the ultraviolet cure are typically monitored.
From the collected ultra-violet cured case studies, a few challenging site-specific conditions were noted
such as a host pipe with varying inner diameter and another site with tight access to manholes requiring
excavation in a dry creek bed. Minor construction issues were noted with heavy rains softening soil and
causing access issues for the heavy equipment vehicles used for the ultraviolet-cured CIPP installation.
Minor technology issues reported included wrinkles caused by varied host pipe diameter and/or tears in
the inner film, but these defects were not expected to significantly impact performance. Future technology
refinement may be needed to provide for a tear-resistant inner film. A case study is highlighted below
from an EPA-funded Water Environment Research Foundation (WERF) field demonstration project of an
innovative ultraviolet-cured CIPP rehabilitation of a wastewater main (Matthews, 2014).
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INNOVATIVE ULTRAVIOLET CURED CIPP IN FRISCO, TEXAS
EPA funded a field demonstration conducted by WERF of the rehabilitation
of 888 ft of 10-inch VCP using Reline America's Blue-TekT-1 product. This
case study is also included in the Web-based renewal database to share
lessons learned on the use of new wastewater main renewal technologies.
This ultra-violet cured CIPP demonstration provided valuable information
on the design, installation, and QA/QC of this innovative technology. The
project documented site preparation activities including temporary bypass,
pre-lining inspection with CCTV, and the cleaning process. The installation
steps were then observed including winching in of the liner, inflation via
compressed air, and completion of the ultraviolet curing process. The
installation for 888 ft of ultraviolet-cured CIPP took place over 3 days. The
liner insertion was completed at a rate of approximately 18 ft/min, while
inflation took 35 minutes per run. The ultraviolet curing was completed in
approximately 3.8 ft/min per run. The QA/QC process was observed and
samples taken for laboratory testing. The main challenges noted at the site
were the varied inner diameter of the host pipe. In addition, certain sections of the liner were reported to be
wrinkled due to a tear on the inner film. However, the minor defects noted did not compromise the overall
strength. The mechanical testing showed that the liner's flexural strength and modulus exceeded the design
requirements. As a result of the demonstration, the vendor later modified the technology design for use of
a more tear resistant inner film (Matthews, 2014).
Another innovation noted in the case studies collected was CIPP suitable for large-diameter applications.
CIPP is generally available in diameters of 4 to 120 inches. However, large diameter installations can be
challenging because of the increased thickness of the liner needed to meet design requirements. Another
new variant on the CIPP technology uses glass fiber reinforced CIPP liners. The additional strength and
stiffness provided by these reinforcing layers allow the liner's overall thickness to be reduced to ease
handling and installation. Two case studies were identified using the Insituform iPlus® Composite, which
is an example of this CIPP innovation suitable for medium to large-diameter pipes from 24 to 97 inches.
The case studies included rehabilitation of a 97-inch RCP sewer main in Texas and a 96-inch concrete
sewer mam in California. The composite liner thickness ranged from 32 to 35 millimeters (1.25 to 1.38
inches) for these case studies. The technology was successfully installed at both sites with no construction
or technology performance issues noted.
4.2 Spiral Wound Linings for Wastewater Mains Case Study Findings
Spiral wound liners are installed in the field from a continuous plastic strip (typically PVC or HDPE).
The strips are joined together onsite via a mechanical inter-locking system activated by a spiral winding
machine or by hand. Grout is typically used to help to seal the annulus and increase the structural stability
of the liner. The strips can also be reinforced with steel for non-circular and larger diameter applications.
A mobile winding machine has been developed for large-scale applications that travels inside the existing
pipe allowing the spiral wound liner to adjust to changes in the host pipe's shape and diameter. Spiral
wound liners can be installed without grout for small, circular pipes and a hot melt adhesive used to hold
the liner at a constant diameter (EPA, 2010). Table 4-2 summarizes the 12 spiral wound lining case
studies for wastewater mains identified as part of the case study collection efforts.
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Table 4-2. Summary of Spiral Wound Lining Case Studies for Wastewater Mains
Company Information
Case Study Information
Vendor
Technology
Name
Headquarter
s Location
Annua
1 Sales
($M)
No.
of
Staff
No. of
Case
Studies
¦
Pipe
Size
Range
(in)
Pipe
Materials
Danby
Danby Panel
Lok (PVC)
Houston, TX
$0,180
2
5
NE, SE
42-96
Brick,
RCP
Sekisui
RibLoc
Australia
Rib line
(HDPE)
Gepps Cross,
South
Australia
$10.66
73
1
SW
36
RCP
Sekisui SPR
Americas
SPR™
(PVC)
Atlanta, GA
$5.4
20
3
NC, SE
48-90
Brick,
Concrete
Sekisui SPR
Americas
SPR EX™
(PVC)
Atlanta, GA
$5.4
20
3
SW
8-12
VCP,
Concrete
Note:
Regions: NE (North East). SE (South East). NC (North Central). SC (South Central). NW (North West). SW (South West). CA (Canada). NNA
(Non-North America)
Pipe Materials: Brick. Vitrified Clay Pipe (VCP). Concrete. Prestressed Concrete Cylinder Pipe (PCCP). Reinforced Concrete Pipe (RCP).
Ductile Iron (DI). Steel. Polyvinyl Chloride (PVC). Polyethylene (PE). Fiberglass Reinforced Plastic Pipe (FRP). Unknown (U). Cast Iron (CI).
Asbestos Cement (AC)
Most of the spiral wound case studies were located in the southeastern and southwestern U.S. Nine of the
case studies are for larger diameter applications on 36 to 96-inch sewer mains. Three of the case studies
are for smaller diameter applications on 8 to 12-inch sewer mains. The types of host pipes rehabilitated
included brick, concrete, RCP, and VCP. The host pipe condition issues addressed included defects in
pipe joints, deteriorating mortar in brick pipes, severe corrosion, hydrogen sulfide corrosion, root
intrusion, excessive infiltration, and new construction over the brick sewer requiring improved structural
performance.
Across the spiral wound case studies, no major issues were noted with products available on the market.
The QA/QC measures specifically employed at the sites were not reported in the case studies. However,
several of these products follow ASTM standards for the material and installation specifications (e.g.,
ASTM F1735, ASTM F1697, ASTM F1698, and ASTM F1741). Site-specific construction challenges
were noted such as the need for debris removal by hand and heavy rains and excessive infiltration from
groundwater and/or a nearby wetland causing the need for bypass pumping and groundwater de-watering.
One large-diameter site experienced grout setting issues and the affected sections had to be removed and
replaced with grout from a new supplier. This demonstrates how critical grout placement is to the quality
of the finished installation. Future improvements could include taking compressive strength samples of
the grout at regular intervals and soundings of the finished liner to test for voids in grouted sections.
4.3 Spray-On Linings for Wastewater Mains Case Study Findings
Spray-on linings used for sewer main rehabilitation consist of either cementitious or polymer-based
materials. Table 4-3 summarizes the 10 spray-on lining case studies for wastewater mains identified as
part of the case study collection efforts. This includes case studies for Geospray™, which is a fiber
reinforced geopolymer spray-applied mortar that is manufactured from a sustainable green material
derived from recycled industrial byproducts. Also, case studies were identified for Permacast®, which is a
specially formulated fiber reinforced cement designed for structural sewer rehabilitation.
The case studies identified were located in the north central and south central U.S. Wastewater main pipe
sizes requiring renewal ranged from 36 to 108 inches with the host pipes consisting primarily of brick,
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concrete, and RCP. The host pipe condition issues addressed included a fully deteriorated host pipe,
section collapses, need for invert repair, excessive leakage, and hydrogen sulfide corrosion.
Table 4-3. Summary of Spray-on Lining Case Studies for Wastewater Mains
Company Information
Case Study Information
Vendor
Technology
Name
Headquarters
Location
Annua
1 Sales
($M)
No.
of
Staff
No. of
Case
Studies
Regions
Pipe
Size
Range
(in)
Pipe
Materials
Milliken
Infrastructure
Solutions,
LLC
GeoSpray™
geopolymer
mortar
Spartansburg,
SC
$0,967
13
8
NC, SC
36 - 108
Brick,
RCP
AP/M
Permaform
Permacast®
structural
liner
Johnston, IA
$0,660
5
2
NC
36-60
Concrete
Note:
Regions: NE (North East). SE (South East). NC (North Central). SC (South Central). NW (North West). SW (South West). CA (Canada). NNA
(Non-North America)
Pipe Materials: Brick, Vitrified Clay Pipe (VCP), Concrete, Prestressed Concrete Cylinder Pipe (PCCP), Reinforced Concrete Pipe (RCP),
Ductile Iron (DI), Steel, Polyvinyl Chloride (PVC), Polyethylene (PE), Fiberglass Reinforced Plastic Pipe (FRP), Unknown (U), Cast Iron (CI),
Asbestos Cement (AC)
No major issues were noted with spray-on lining products available on the market. Surface preparation is
an important first step in the spray-on lining process. Pressure washing was used in all cases for cleaning
and supplemented at some sites with high pressure air. The design thickness of the spray-on liners ranged
from approximately 1.5 to 2.0 inches for the Geospray™ product and 0.5 inch for the Permacast® product.
The types of QA/QC activities included compressive strength testing (ASTM CI09), depth gauges, and
post-lining CCTV. As described below, one site experienced excessive infiltration issues which required
the lining to be manually sprayed versus the automated sled application. Positive experiences were
reported for use of the technology with odd shaped pipes and pipes where minimal capacity reduction was
desired. A case study from an EPA field demonstration project of an innovative geopolymer spray-
applied mortar rehabilitation of a sewer main is highlighted below (EPA, 2014a).
INNOVATIVE SPRAY-APPLIED GEOPOLYMER MORTAR IN HOUSTON, TEXAS
EPA performed an evaluation of an innovative geopolymer spray-applied
mortar for wastewater main rehabilitation in Houston, Texas. This case study I
is also included in the Web-based renewal database. The GeoSpray™ product I
was used to rehabilitate a 60-inch RCP sewer main leading to the wastewater I
treatment plant where the 25-ft depth of the pipe and the need to rapidly return I
to service precluded open cut excavation. The RCP host pipe was severely I
deteriorated with corroded and exposed steel reinforcements and had several
locations of heavy infiltration. The heavy infiltration conditions eventually led to the product being
manually spray applied by hand rather than using a sled. The material was successfully installed manually
and the post-lining CCTV inspection showed the rehabilitated pipe to be infiltration free, with no signs of
exposed rebar or cracking, and with no significant defects. A lining thickness of approximately 3.3 inches
was sprayed in the pipe, which is more than the minimum design value of 1.9 inch. The third-party test
results for compressive strength averaged 8,635 psi at 28 days and passed the required criteria.
Recommendations were made related to improving QA/QC through measuring the "as installed" lining
thickness, bond strength testing, and the use of shaker tables to minimize voids in samples (EPA, 2014a).
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4.4 RehabAnalytics Data Review for Wastewater Mains
The RehabAnalytics page contains summary information on case studies for wastewater main renewal
including total case study counts and an automated plotting of normalized cost data. As shown in Figure
4-3, the largest number of case studies collected was for CIPP (27), followed by ultraviolet-cured CIPP
(15), spiral wound lining (12), and sprav-on lining (10).
Frequency Plot
30
27
26 !¦ I
1
3 20
L I L«
0 12
1 10 I r 10
'JJLi'ili. . . LI.
0 o =¦ s i I g I :i i » i
°- V i | l £ | # -s
S S 3 o * i I
.2 o dj £
II i
1 = ">
s
U
Different Methods
Figure 4-3. RehabAnalytics Total Count Summary for Wastewater Case Studies
Bid cost data were also collected for wastewater main renewal by sliplining to benchmark the innovative
technology costs. The trenchless technology cost data collected were normalized to the host pipe footage
and diameter for the project as shown in the examples in Figures 4-4 and 4-5. Cost plots for additional
trenchless technologies can be viewed on the RehabAnalytics page. Cost was obtained for only one sewer
main project for the ultraviolet-cured CIPP at $7 per linear foot per inch diameter. The spiral wound
lining normalized costs for sewer mains ranged from $2 to $12 per linear foot per inch diameter (Figure
4-4). The spray-on lining nonnalized costs for sewer mains ranged from $3 to $9 per linear foot per inch
diameter (Figure 4-5).
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Spiral Wound
Q
I
*
s
U)
o
O
¦t;
5
° Sewer Slip lining
o
o
8
O o
O o
o
o
o
o
o
8 o
O O
o
o o ° o
°A °
o
o
V
Diameter(in.)
Figure 4-4. RehabAnalytics Normalized Costs Data for Spiral Wound Lining of Sewer Mains
Spray/Spincast Lining
.12
Q
I
§
V-J
o
O
•t;
5
12-,
11-
10-
9-
o Sewer Slip lining
(y Spray/Spincast Lining
o
8 i
~
o
o
O o
o
o
o
—o
o o ° °
~
° o
O o
o
o
o o
O O O °0 rt
O o °
o
o
20
40
60
80
Diameter(in.)
Figure 4-5. RehabAnalytics Normalized Costs Data for Spray-On Lining of Sewer Mains
25
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Section 5.0: CONCLUSIONS
An increased understanding of various renewal options will help utilities to select the most viable and
cost-effective technologies to shore up their aging water infrastructure and extend its useful life. This
research effort involved the collection of case studies on the use of various pipeline renewal methods and
provides the information in an online searchable database. The conclusions and recommendations to
further advance the use of innovative and cost-effective renewal technologies are as follows:
• Renewal case studies were developed for both water and sewer mains that included the
technologies used; the conditions under which the technology was implemented; costs; lessons
learned; and utility contact information. More than 180 case studies were collected. The case
studies were categorized by several geographic regions including northeast, southeast, north
central, south central, northwest, and southwest, Canada, and non-North American. The following
trends were noted related to the regional distribution of innovative renewal technology case
studies.
o The most water main renewal technology case studies were identified in the northeast (18%).
This was closely followed by the southwest (16%) and north central (16%) U.S. regions. A
large number of water main renewal case studies were identified in Canada or outside North
America (29%) suggesting that the use of these technologies may be more prevalent outside
the U.S. and that there is room for growth in the U.S. market as the demand for water main
renewal services increases overtime.
o The most wastewater main renewal case studies were identified in the north central U.S.
region at 25%. This was followed by the northeast (19%) and southwest (19%) U.S. regions.
In contrast to water main renewal, only 9% of the case studies identified were located in
Canada or outside North America. This reflects the stronger domestic market for wastewater
main renewal due to enhanced regulatory drivers.
• For water main renewal, spray-on lining, CIPP, and close-fit lining were identified as the most
prevalent methods from the case study collection efforts. Lessons learned and the needs for future
improvements for each of these renewal technologies were summarized in Section 3.0. Future
technology refinement needs included ensuring minimum thicknesses are met throughout an
installation for spray-on linings. Adjusting cleaning methods to avoid damage to corporation
stops and improvements in robotic reinstatement of service lines may help to reduce the need for
excavations to reinstate service on water main CIPP projects. In addition, close attention is
needed to avoid weld and pull head breakage issues at close-fit lining applications for water
mains.
• For wastewater main renewal, conventional CIPP is by far the dominant technology. The case
study results were focused on a discussion of innovations identified in ultraviolet-cured CIPP and
reinforced CIPP liners, spiral wound lining, and spray-on lining for sewer mains. After
conventional CIPP, these four technologies were identified as the next most prevalent methods
used for sewer main renewal from the case study collection efforts. Lessons learned and the needs
for future improvements for each of these technologies were summarized in Section 4.0. A
recommended future technology refinement is a tear-resistant inner film for ultraviolet-cured
CIPP applications. Lessons learned include the importance of grouting to a successful spiral
wound lining installation, and the need for compressive strength testing and soundings of the
grout. For spray-on lining products, similar to findings for water main applications, QA/QC
measures could be improved to ensure that the "as installed" lining thickness is measured and a
uniform thickness achieved throughout the installation.
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• Cost data curves were incorporated into the Rehab Analytics tool based on bid cost data collected
for conventional technologies such as CML for water mains and sliplining for sewer mains. A
data mining algorithm was then deployed to extract and normalize the cost data from the case
studies and to plot for ease of review. In general, cost data was challenging to collect for this
study as vendors may not disclose this information and utilities do not always track the individual
costs for a single innovative technology project if it is part of a larger contract. Costs can also
vary widely based on site-specific conditions such as cleaning needs, dewatering needs, the need
for night work to avoid traffic disruption, and other factors. The following trends were noted in
the cost of innovative renewal technology case studies:
o For water main renewal, the spray-on polymeric lining normalized costs ranged from $3 to
$35 per linear foot per inch diameter. The water main CIPP normalized costs ranged from
$10 to $45 per linear foot per inch diameter. The close-fit lining normalized costs for water
mains ranged from $3 to $21 per linear foot per inch diameter.
o For sewer main renewal, the cost was obtained for only one project for the ultraviolet-cured
CIPP at $7 per linear foot per inch diameter. The spiral wound lining normalized costs for
sewer mains ranged from $2 to $12 per linear foot per inch diameter. The spray-on lining
normalized costs for sewer mains ranged from $3 to $9 per linear foot per inch.
The Web-based, searchable tool created as part of this research project can be used by utility personnel to
review the technology performance and cost data described above, as well as case study references. The
database can be accessed at: http://138.47.78.37/Retrospective. The database will be publicized to the
water infrastructure community through release of this report on the EPA Web site. Utilities are
encouraged to review the case studies and to support future expansion of the online database through the
addition of their own case study information.
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Section 6.0: REFERENCES
Ellison, D., F. Sever, P. Oram, W. Lovins, A. Romer, S. Duranceau, and G. Bell. 2010. "Global Review
of Spray-On Structural Lining Technologies." Water Research Foundation Project No. 4095, Denver,
CO, http://www.waterrf.org/PublicReportLibrarv/4095.pdf
EPA. 2010. State of Technology for Rehabilitation of Wastewater Collection Systems. EPA/600/R-10/078,
U.S. EPA, Office of Research and Development, Cincinnati, OH, Jul., 325 pp.,
http://nepis.epa.gov/Adobe/PDF/P1008C45.pdf.
EPA. 2011. Decision Support for Renewal of Wastewater Collection and Water Distribution Systems.
EPA/600/R-11/077, U.S. EPA, Office of Research and Development. Cincinnati, OH, Jul., 70 pp.,
http://nepis.epa.gov/Exe/ZvPURL.cgi?Dockev=P 100BWUR.TXT
EPA. 2012a. Performance Evaluation of Innovative Water Main Rehabilitation Sprav-On Lining Product
in Somerville, NJ. EPA/600/R-12/009, U.S. EPA, Office of Research and Development, Cincinnati,
OH, Feb., 212 pp., http://nepis.epa.gov/Exe/ZvPURL.cgi?Dockev=P 100GDZH.TXT
EPA. 2012b. Performance Evaluation of Innovative Water Main Rehabilitation Ciired-in-Place Pipe
Lining Product in Cleveland. EPA/600/R-12/012, U.S. EPA, Office of Research and Development,
Cincinnati, OH, Feb., 63 pp., http://nepis.epa.gov/Exe/ZyPURL.cgi?Dockev=P 100LHXY.TXT
EPA. 2013. State of Technology for Rehabilitation of Water Distribution Systems. EPA/600/R-13/036.
U.S. EPA, Office of Research and Development, Cincinnati, OH, Mar., 212 pp.,
http://nepis.epa.gov/Adobe/PDF/P100GDZH.pdf.
EPA. 2014a. Performance Evaluation of an Innovative Fiber Reinforced Geopolvmer Spray-Applied
Mortar for Large-Diameter Wastewater Main Rehabilitation in Houston, Texas. EPA/600/R-14/443.
U.S. EPA, Office of Research and Development, Cincinnati, OH, Dec., 63 pp.,
http://nepis.epa.gov/Exe/ZyPURL.cgi?Dockev=P 100LHXY.TXT
EPA. 2014b. National Database Structure for Life Cycle Performance Assessment of Water and
Wastewater Rehabilitation Technologies (Retrospective Evaluation). EPA/600/R-14/251, U.S. EPA,
Office of Research and Development, Cincinnati, OH, Sept, 247 pp.,
http://nepis.epa.gov/Exe/ZvPURL.cgi?Dockev=P100LDG0.txt
EPA. 2016a. Testing and Performance Evaluation of an Innovative Internal Pipe Sealing System for
Wastewater Main Rehabilitation. EPA/600/R-15/326., U.S. EPA, Office of Research and
Development, Cincinnati, OH, Jan., 38 pp.,
http://nepis.epa. gov/Exe/ZyPURL.cgi?Dockev=P 100Q12N.TXT
EPA. 2016b. Clean Watersheds Needs Survey 2012 Report to Congress. EPA/830/R-15005. U.S. EPA,
Office of Wastewater Management, Washington, D.C., Jan., 41 pp.,
https://www.epa.gov/sites/production/files/2015-12/documents/cwns 2012 report to congress-508-
opt.pdf
Matthews, J. 2014. Demonstration and Evaluation of Innovative Wastewater Main Rehabilitation
Technologies. Project Number INFR4R11. Water Environment Research Foundation (WERF).
Alexandria, VA, Jun, 61 pp.,
https://www.werf. org/a/ka/Search/ResearchProfile.aspx?ReportId=INFR4Rl 1
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UC. 2016. "Underground Construction 19th Annual Municipal Survey." Underground Construction. Feb.,
Vol. 71, No. 2, https://ucononline.com/2016/02/17/underground-construction-19th-annual-municipal-
survey/
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