Released on: January 24, 2008, 11:51 am

Press Release Author: Sharon M. Bueno is managing editor of Trenchless Technology.

Industry: Environment

Press Release Summary:
http://www.trenchlessonline.com/index/webapp-stories-action?id=423&archive=yes&Issue=2007-12-01


Press Release Body: Miami-Dade Water and Sewer Department (MDWSD) recently completed
one of the largest lateral lining projects in the country, rehabbing approximately
1,200 laterals in residential and commercial areas at a price tag of just under $5
million.

The 15-month lateral project was part of a pilot program that MDWSD undertook to
research and evaluate a variety of lining techniques in addressing the condition of
its laterals and stopping infiltration-and-inflow (I/I). In the past, I/I was
handled through traditional dig-and-replace methods.

The pilot project, called the Miami-Dade Pilot Lateral Lining Project, was a
two-part program that first inspected and identified the problematic laterals and
then had them lined using trenchless technologies.
"The main purpose was to determine whether lateral relining was a solution to our
peak-flow problems in the system," explains Rod Lovett, chief of the MDWSD sewerage
collection division. "Most of our laterals are conventional replacements where we go
and dig them up and replace them. Being in Miami-Dade County, that typically is the
cheapest way to go. However, we have some exceptions to that rule and we really
wanted to test the lateral linings to see if they are a solution to the leaks in the
system."

The project engineer was Hazen and Sawyer. MDWSD put the project out to bid and
awarded it to Metro Services Inc., which utilized Perma-Liner's InnerSeal and
standard Perma-Liner systems on approximately 1,200 laterals in the system between
June 2006 and November 2007. As the general contractor, Metro Services handled the
majority of the laterals but some work was subbed out.

"By the sheer number of laterals relined, this was probably one of the largest such
projects in the country," says Jorge Godoy, president of Metro Services Inc.
"[MDWSD] identified the laterals that were leaking. Our primary job was to eliminate
inflow."

The area of the project involved about 80 percent residential and 20 percent
business. Miami-Dade's pipes are mostly made of clay but there is a fair amount of
cast-iron, which were turburculated and required cleaning before lining. The
Miami-Dade system also has more than 1,400 pump stations, with pipes 6 to 8 in. in
diameter. The laterals range from 8 ft in length to as long as 100 ft. The laterals
range in age from 20 to 50 years old and suffer from heavy infiltration, cracks and
root intrusion.

"The condition of Miami-Dade's laterals is typical of the rest of the country,
except for the fact that Miami-Dade has a very high water table and all the pipes
are under water," explains Steve Cudd, CIPP project manager for Metro Services Inc.
"Like a lot of cities, Miami-Dade addressed its pump stations and mainlines. After
those, they realized that the next part of the process were the laterals. Because
although they eliminated a lot of the inflow into the mainlines, they had not
addressed the laterals and there was a great deal of water coming in there as well."

To assess the condition of the pipes and laterals to identify the source of
rain-induced I/I that comes into the system during and after heavy rains, MDWSD used
a sanitary sewer evaluation survey (SSES), which uses various equipment and
techniques to detect sewer pipe defects, blockages and capacity problems. These
techniques include smoke tests, dye tests, closed-circuit TV, flow monitoring, rain
monitoring, building service connection location/inspection and flow isolation.

Once MDWSD identified the problematic laterals, issuances were given to Metro
Services to begin work. First, Metro crews used a CUES lateral investigative unit to
look at the selected laterals to determine which ones needed to be cleaned and
prepped before liner installation could take place. Crews utilized a Perma-Liner
InnerSeal unit with a 28-ft trailer, which is used as a turnkey operation, to do the
lining. A smaller trailer was used when the standard Perma-Liner process was used.

How InnerSeal Works

Perma-Liner's InnerSeal, which Metro Services used on a majority of the laterals, is
a non-intrusive lining method to correct lateral pipeline and mainline sewer
pipeline connection problems. The materials are designed to be placed from within
the main sewer pipe and launched into the lateral, creating a watertight seal at the
main and lateral connection point. The lateral is also lined at the same time,
correcting any damaged pipe sections and preventing roots from growing into the
pipeline. The InnerSeal resin technology has excellent bonding properties in all
pipe materials and does not contain styrene. Resin formulation is an ambient cure
and can be modified for hot water or steam curing.

"The process itself takes about two hours and we could easily do four laterals at a
time," Cudd says. "We would do the first one and while it was curing, we would leave
air on it and go start another and then repeat the process."

Metro typically used six-person crews for this project. Cudd says Metro's goal was
to line five to seven laterals a day. "And we usually completed seven [laterals] a
day," he notes.

Though huge in size, the project itself didn't present any special challenges for
Metro, Cudd says, explaining the project simply: "We just had to go through the
cleanout, check the length of the lateral, status of the pipe and then clean it and
reline it." Lateral ownership wasn't an issue as the laterals were addressed from
the property line back to the mainline. If a cleanout needed to be installed, it was
done on the county side of the property line, Cudd says.

Both Metro and MDWSD were more than satisfied with the project's outcome. MDWSD is
still waiting for enough qualified rain event data to fully analyze the results of
the pilot program.

"We were initially pleased with the results of the lateral work and so far they have
held up and have given us good service," Lovett says. "They've eliminated 100
percent of the leaks we had in those laterals."
Beyond the project's final results, Lovett was also pleased with the use of the
Perma-Liner process, which he says gives a 50-year life expectancy. "The InnerSeals
were very good," he says. "There was some discussion before we started that the
InnerSeals wouldn't adhere against the normal pipe material or mainline lining
material. We found that to be untrue and they seal well against both materials. They
stopped the leaks."


Web Site:
http://www.trenchlessonline.com/index/webapp-stories-action?id=423&archive=yes&Issue=2007-12-01


Contact Details: Perma-Liner Industries, Inc.
6196 126th Avenue North
Largo, Fl. 33773
Tel: 727-507-9749
Fax: 727-507-9849
jerry @perma-liner.com
morgan@perma-liner.com
www.perma-liner.com