Replacing a Calgary sewer line, one step at a time.

01 /What does replacing a sewer line in Calgary involve?

Replacing a sewer line in Calgary is a short dig wrapped in a longer process. The crew is usually on site for one to three days for an open-cut replacement, about a day for lining or a spot repair, and one to two days for pipe bursting. Around those days sit the steps that decide whether the job goes smoothly: camera footage and a written scope, a City of Calgary plumbing permit, locates for every buried line, an inspection before backfill, restoration of whatever was dug up, and a file of records you will keep for as long as you own the house.

1. Scope it from footage

   Map every defect to the yard, mark the property line, and write down the metres, method and material. See setting the scope.

2. Choose who does it

   Check the City business licence, trade certification, WCB clearance and insurance. See hiring a contractor.

3. Permit and locates

   A plumbing permit, public locates through Utility Safety Partners, and a private locate for your own lateral.

4. Dig, lay and inspect

   Trench protection past 1.5 m, pipe laid to grade, inspection while everything is visible. See the day-by-day guide.

5. Backfill, restore and record

   Compacted lifts, restoration by surface, and the after-video, permit and sketch filed together.

Every page on this site follows that sequence. If you only read one, read the replacement process step by step; if you want to see your own timeline, use the Replacement Timeline Planner.

02 /What makes a sewer replacement in Calgary different?

Four local conditions shape almost every Calgary job. The first is depth. In a house with a basement, the drain leaves below the basement floor, so the lateral starts deep and keeps falling toward the City main. Most of its length sits deeper than 1.5 m, which is where Alberta's Occupational Health and Safety Code requires trench walls to be cut back or protected before anyone works in them.

The second is the ground. The Alberta Geological Survey's mapping of the Calgary urban area describes glacial till, thick lake sediments of silt and very fine sand, and, in many places, quartzite gravel or hard sandstone under a thin cover, a combination it notes makes digging difficult. A replacement trench also follows the old one through previously dug soil, which Alberta's rules never treat as the most stable class. The soils and depth page explains what that means on site.

The third is the climate. Frost has to be broken or thawed before a winter dig, frozen spoil cannot be compacted, and a chinook can soften an open trench overnight. Alberta's Code is explicit that naturally frozen soil is not a substitute for trench protection. The fourth is ownership. The City of Calgary's published position is that it owns and maintains the sanitary service pipe from the main to the property line, and the homeowner owns and maintains it from the property line to the house. The property line is often behind the sidewalk, and the boulevard is City right-of-way, so a dig that reaches it needs City permits. Working on the City side covers that process.

03 /What do the City's records tell you before you dig?

The City of Calgary publishes the material and install year of the City-owned section of every residential sanitary service line in its open data. A HAUSE analysis of that dataset, covering 367,397 City-side service lines, finds about 20 percent coded TIL, the City's tile code, generally read as clay tile; 3.3 percent cast iron; 66.5 percent PVC; and 1.1 percent already relined with a cured-in-place liner. Clay tile dominates City-side installs of the 1960s and 1970s, and PVC takes over from the 1980s.

Those records cover only the section from the main to the property line. Your private section can be a different material and a different age, and only a camera tells you what it is. What the records do tell you is what your new pipe will have to join at the property line, and how likely it is that the original private pipe was clay or cast iron. In communities such as Maple Ridge, Rundle and Willow Park, more than 95 percent of City-side records carry the TIL code; in Rosscarrock and St. Andrews Heights, more than half are cast iron. CalgarySewers.ca maps the records community by community.

04 /How does this site fit with the rest of the HAUSE Sewer network?

CalgarySewerReplacement.ca covers the process of a Calgary replacement. Sister sites cover the questions around it, so each can go deep without repeating the others.

• Costs, financing, insurance and buying or selling an older Calgary home: CalgarySewerReplacement.com. This site's cost drivers page explains where in the process the money goes.
• Calgary's sewer system as data and civics: CalgarySewers.ca.
• Backups, clogs, roots and freeze-ups right now: CalgarySewers.com.
• Repair, reline or replace, and which method suits which pipe: SewerReplacement.ca.
• Camera inspections and reading a report: SewerInspector.ca.
• The pipe bursting method in depth: PipeBursting.ca.
• Cleaning a basement after sewage gets in: SewageCleanup.ca.
• Every sewer service lane across Canada in one place: the network hub, Sewers.ca.

Before the first call, three planning guides save time: finding where your sewer line runs, what a Calgary quote must include, and living at home during the job. Rebuilds and infills start instead with running a new sewer line to the street, and defects inside the foundation with under-slab replacement.

HAUSE Sewer publishes independent information and passes along quote requests; it does not dig, lay pipe or hold permits, and no sewer work is done by this site. When you are ready, request quotes with your footage, locate marks and scope, and use the Permit & Locate Checklist to keep the paperwork on track.

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