This project consisted of the cleaning of over 90 existing CSP highway culverts from 450mm to 1200mm in diameter, and the CIPP rehabilitation of 11 of these culverts. The work was conducted on Highway 41, a busy highway for cottagers and an entrance way to Bon-Echo Provincial Park. To protect the water courses, sediment control barriers were used, and the liners were steam cured to prevent spills of cure water into the environment.

CWW has the ability and the proven experience to complete the rehabilitation of culverts where access to only one extremity exists. In the case where the inlet or the outlet is inaccessible due to the presence of trees, a steep drop, or swampy grounds, the CIPP liner can be installed entirely from the other extremity. The major advantage is the reduced costs typically associated with the building of temporary access roads. Through the application of proven and tested CWW rehabilitation methodologies, access roads to either end are not required. In addition, the rehabilitation solution is non-invasive and environmentally responsible. Trees are undamaged, and water streams, fish, animal habitats, and the surrounding environment are undisturbed.

For this project, traffic disruption was minimal, and the culvert rehabilitation was completed in 11 days, a significant advantage over conventional dig-and replace methods which typically require weeks of complete road closures and detours.

This project consisted of over 2,200m of CIPP sewer rehabilitation, ranging in diameter from 200mm to 900mm, including the replacement of several manholes and sewer sections. The excavation aspect of the project was sub-contracted to a local contractor and managed by CWW.

Quebec City had a series of additional road reconstruction projects underway in the vicinity of our lining, which required precise scheduling on our part to avoid and eliminate any potential conflicts.

Several of the sewers slated for rehabilitation were located on high traffic volume streets, which required the submission, approval, and implementation of complex traffic control plans. The most challenging part of this project was the rehabilitation of a 900mm CSP storm sewer outfall. The outfall consisted of two 100m sections, with the downstream situated halfway down a steep, rocky ravine, and several meters above the Rivière De-Cap-Rouge. These two sections were cured with hot water; and due to exacting environmental requirements, the cure water had to be pumped from the liner upon completion and transported for treatment.

All of the liners were wet-out (resin impregnated) in our facility in Ottawa and transported in a refrigerated truck to Quebec City. The 450mm diameter and smaller liners were inverted with air and steam-cured. Larger diameter liners were inverted and cured with water.
With the existence of two CWW steam-cure units and one hot water boiler unit in our fleet, we had the flexibility to meet the tight scheduling requirements.

The project was the City of Ottawa’s first contract calling for the CIPP rehabilitation of residential sewer laterals while also requiring spot repair excavations prior to lining.

Fifty addresses were selected by the City of Ottawa for this contract. Due to breaks and sumps, the sewer laterals could not be rehabilitated by CIPP without a prior spot repair excavation. Similarly, these laterals could not be repaired entirely by conventional trenching excavation methods for a number of reasons including the presence of trees. The City of Ottawa outlined specific requirements for each address in order to minimize inconveniences to the individual homeowners, and to minimize site disruptions and damages to surrounding trees and the surrounding environment, while at the same time minimizing overall costs.

In one instance, the sewer lateral ran under a cement porch, then under grass and under a large city tree before reaching the City main. There was a break in the pipe beneath the grass, including the presence of a highly invasive network of roots. There were cracks and fractures at various locations along the length of the pipe. The solution was to excavate and repair the break, and then install a CIPP liner over the entire length of pipe from the cleanout to the City main. In this case excavation was required because the liner could not be installed through the broken section, given that the stated obstacles could not be disturbed.

CWW engaged the services of a sub-contractor for the excavation portion of the project. The work was coordinated by CWW and involved first inspecting the pipe, locating the section of sewer that required excavation, spot repair, landscaping reinstatements, the rehabilitation by CIPP, and the final video inspection.

This extremely complex project was tendered by the City of Ottawa, and CWW was the only bidder. The work consisted of cleaning and televising over 600m of 1800mm storm sewer and outfalls. The specific sewer, built in the mid 1950s, had never been maintained; and investigations determined that there was a large accumulation of sediment present in the storm sewer.

The outfall is located approximately 20 feet under the Ottawa River in the Nepean Bay area of the City.

CWW employed professional divers to install a 72-inch diameter plug to ensure that sediment would not enter the Ottawa River. Among a series of specialized equipment brought to bear to complete this complicated challenge, four 20,000 gallon Weir tanks were used simultaneously to separate the solid debris from the water. The clean water was then recycled and used by the flusher unit for cleaning operations. Over 200 tons of debris was removed from the sewer and transported to the Ministry of Environment-approved dump pad at our facility.

This project was completed in the dead of winter and on schedule, and before the spring melt.

CWW first obtained a contract with St-Vincent Hospital consisting of televising and locating the storm and sanitary drains in the basement of the original building on Cambridge St. Originally built in 1932, the hospital had received major renovations including a new addition in 2001.CWW investigated over 1000m of sewer drains by push sewer camera.

Following CWW’s report, and at the request of the client, most drains were cleaned and flushed while others were selected by the client for rehabilitation by CIPP. CWW re-lined approximately 20m of 4 inch diameter sanitary drains under the concrete floor in the hospital’s main kitchen area. The work was conducted overnight when the flow would be minimal, and the disruptions to the hospital staff and patients would be greatly reduced. The work was complete by the following morning, allowing the drains to be used at full capacity.

This project consisted of the CIPP rehabilitation of approximately 600 residential sewer laterals from the existing cleanout to the City main. The full length of over 9,000m of sewer first had to be televised, cleaned, and prepped before the liner installation.

The most common defect in lateral sewers is the presence of roots, which can easily be removed by using our 15,000-psi high-pressure water unit. When further investigation of the lateral was required, CWW depended on its LAMP (Lateral and Mainline Probe) camera, which provides total inspection of the lateral from the main sewer.

CWW uses a felt liner impregnated with epoxy resin, which is then inverted with air and cured with hot water. The rehabilitation of sewer laterals by CIPP is a prudent and cost-effective alternative to the conventional dig-and-replace method, as costs associated with the reinstatement of existing landscaping, trees, utilities and roadways is eliminated. Further, our experienced technicians often complete the entire CIPP process in less than 5 hours.

CWW reinstated weeping tile connections internally through the use of a robotic cutter. It is also important to note that the CIPP process remains unaffected by colder weather, which is another significant advantage over traditional excavation methods.

This project consisted of approximately 2,400m of preliminary CCTV investigation followed by 2,400m of CIPP installation. CWW recommended lining candidates for the approval of the City of Ottawa, and two installation methods were used: air inversion with steam cure, and water inversion with hot water cure. 1200m of 30” diameter and larger CIPP liners were installed. 100m of 42” diameter and larger CIPP liners were also installed.