Zwald Transport Inc

This is the 2nd report on Zwald industrial in the area of Sewer Repair, sewer relining using the Perma-Liner cured-in-place process. This was a repair on the sewer of my father's house in Portland to get it ready (along with other repairs) to be listed on the real estate market for sale. His sewer was very root clogged, consisting of concrete 3 foot pipe sections, with heavy root intrusions at every joint (old birch trees in the parking strip, crab apple trees in the neighbors parking strip). Additionally the pipe traveled diagonally under the driveway to the street so a conventional trench replacement would have required extensive concrete cutting and replacement. The Zwald team did the up-front dvd showing the sewer condition all the way to the sewer main. They sent an estimate and said the relining would be required to the property line. Then later we were told that the relining was required by the city to occur to the curb. Unfortunately in the street in the city's area of responsibility there is a severe void and root ball above the sewer line, and had the city allowed Zwald to reline to the sewer main that would have now been taken care of (for only another $700, besides). The day of the project the Zwald team came out and also hired an excavator to dig down the 7-8 feet next to the house. During the digging there was some surprise that the downspouts were also connected to the sewer (it is called a combination sewer) I am sure I had mentioned that early on. The downspout connection had to be removed and the downspouts now drain to the lawn. That is extra work that we had to do. It would be nice if Zwald also provided an extra cost dry well disconnect option in this case. At this point I left and the Zwald team handled the job the rest of the day. I understand they ran a scour jet to remove all of the roots in the pipe before doing the liner. They left a dvd of the completed relining. They also created a good looking rock garden with some of the left over large 6" - 10" diameter rocks (very rocky ground, remnant of the Missoula Floods through Portland at the end of the last ice age). At this point there was difficultly with approval of the City of Portland. The inspector seemed completely unfamiliar with the Perma-liner process even though another inspector had approved a relining previously. And they insisted that a positive connection be made to the city's part of the sewer, even though the liner is epoxied to the inside of the pipe, which is a positive connection. To make a long story short, the Zwald team had to come back out and cut concrete and dig down to the pipe at the curb, cut the pipe and liner, and insert a pvc pipe section with rubber adapters and hose clamps. They actually had to chisel some of the liner out of the pipe, it was obviously firmly attached. The job was then approved by the city inspector. Zwald had a concrete contractor replace the cut sidewalk and curb. We are very positive on the Perma-liner process and Zwald. I did additional research online and found that the cured Perma-liner has been independently lab tested to greater than 3000psi, which is as strong as the concrete pipe it is lining. Zwald had the concrete patched back up and ready to go by the end of the afternoon. Attached are showing photos of the same location before and after it was lined, and a chunk of the liner that they chiseled out of the pipe when the City of Portland required a "positive connection". Note the concrete aggregrate embedded in the liner. A final note: The Perma-Liner has a 50 year written warranty. The City of Portland should embrace this process. They use relining for their sewer mains. They need to make it easier, less invasive and costly for people to repair their sewers. They should also allow the contractors to reline to the sewer main and then pay the contractor for the extra footage. That way there would be one continuous, seamless liner from house to sewer main without extensive digging.

This job was in the area of sewer repair. We had had a first clog in our sewer line about 4 years ago at 11pm and night and was not pleasant. Had to call a roto rooter type company. Then another clog happened about 1 year later. We had had a video inspection and knew there were some gaps, roots, and shifting. The sewer line goes underneath our hot tub slab, and this year it looked from the water level that one corner of the tub was sinking and our thought was that the soil underneath the slab was washing away. So we had to do something. I had searched before and found the Perma-liner technology (www.perma-liner.com). But could not locate a local contractor even after calling the national company. I tried again this year and was directed to the only Oregon contractor, Zwald Industrial in Tillamook Oregon. The Zwald team came out and did a camera inspection of the sewer line and gave us a dvd of the inspection and a written report that showed all problem areas. Our line comes out of the house, goes under the hot tub slab next to the house, then turns 45 degrees to the south west and goes under a lot of landscaping to the sewer main. Total length 83 feet. So we decided to go with Zwald and the Perma-liner process. They gave us a bid and set a target date. On the target date the Zwald team came out and installed the liner. What they did was dig down to the sewer next to the hot tub, about 3 feet, then remove one of the 3 foot concrete sections of pipe. They then prepared the liner by cutting it to length out in the street and turning it inside out. Then they mixed their epoxy resin and poured it into the inverted liner, which since it was inverted had the outside of the liner on the inside. They then roll over the liner with a roller to evenly cover the entire surface of the liner. They also have what is called a calibration tube which is like a balloon and is what presses the liner to the inside of the existing pipe. This is also cut to length. Then they rolled up the liner and place it into a pressure tank. They then rolled the tank to the hole they had dug, and attach what is called an inversion head to a hose, and to the pressure tank. The tank was pressurized and they started the inversion process into the existing sewer line. The liner quickly inverted and unrolled to the length of the line, then they inserted the calibration tube into the liner and shot it down the line. Then they held the calibration tube at 12 psi for 3 hours while the liner cured. While the liner was curing, they created a similar repair that is called a spot repair, to go under the hot tub. This is the same material as the liner, and uses the blow-up calibration tube, but was pulled through with a rope to the sewer clean-out. After the 3 hour cure, they trimmed the liners, and replace the missing 3-foot section of sewer line with a pvc pipe and clamps at either end. They then ended the afternoon by creating a video dvd showing the original sewer, and the newly lined sewer. This dvd was also given to the city inspector who approved the sewer repair.