Skipping the request because "it's just a post"[1]
What happens
A post or planting hole can pierce a shallow gas line or power cable.
How to avoid it
File a request for any hole in the ground, small or large.
Guide
Before you dig: locates, permits and property lines
Every project that digs starts the same way: a free Info-Excavation request at least 4 business days ahead, a check of municipal permits and property lines, then careful digging near the marks. This guide explains each step, the trench safety rules and what to do if a line gets hit.
Draft.This guide is a draft. It has not yet been reviewed by an experienced installer or an engineer. Quantities and times come from the engine; the text may still change.
In this guide
Your project
The quantities below come from the calculator, for the guide's typical project, and drive its times.
| Material | Quantity |
|---|---|
| Bank volume of soil to dig | 2.4 m³ (3.1 cu yd) |
| Swollen volume to haul | 3.4 m³ (4.5 cu yd) |
| Mass of spoil | 4.56 t |
| 10-wheel truck trips | 1 truckload |
| Machine hours | 1.4 machine h |
| Depth | 0.6 m (2 ft) |
| Area dug | 4 m² (43.1 sq ft) |
Computed for: Quebec (province)
Estimated total working time
- Beginner
- 28 person-h11 to 77 person-h
- Intermediate
- 20 person-h9 to 47 person-h
Phase 1 · Assessment
Plan what you will dig
Under the safety rules, digging means making any hole in the ground: a drain trench or a patio base, but also a fence post hole or a tree pit. Before any request, define the exact area, the depth and what you will do with the soil. The calculator gives the bank volume, the swollen volume to haul and the number of truck trips.
Also find what belongs to you: private wires and pipes (garage, spa, lighting, irrigation, well, septic system) are not marked by any public network. And know where your property lines run.
01Mark out the area and find your private lines[1, 2]
- Mark the whole area you will dig on the ground with paint or flags, including the machine's access and where spoil goes.
- Note the planned depth and the volume the calculator gives.
- List the private lines you know of: a wire to a garage or shed, a spa, lighting, irrigation, a gas line to a barbecue, a well, a septic system. Look for clues: boxes, cleanouts, conduits going into the ground.
- Decide where spoil will go: hauled away, kept on site or reused.
Done when : The area is marked on the ground, the depth and the spoil plan are written down, and your list of private lines is done.
02Confirm the property lines[2, 3, 4]
- Get out your certificate of location: it shows the lot lines and where the buildings sit.
- If the work comes close to a line, or the markers cannot be found, hire a land surveyor.
- Check the setback your municipality requires for the planned structure (wall, fence, pool, parking).
- Tell your neighbour if the work runs along the line.
Done when : You know where the lines run near the work area, from the certificate of location or a surveyor, and you know the setback that applies.
03Set the work calendar[2, 5, 6]
- Pick the date of the first shovelful, then count back at least 4 business days, without weekends or holidays: that is the deadline for your Info-Excavation request.
- Estimate how long the work will take. If it may run past the request's end date, 180 days at most, plan to renew it.
- Avoid placing stone or a base on frozen ground, or with frozen stone: from November to March, plan digging only or wait for the thaw.
- In spring, thaw load restrictions can reduce or delay truck deliveries: confirm with the supplier.
Done when : You have a start date, the locate request deadline and the validity end date to watch, written in your calendar.
Phase 2 · Permits and locates
Locate request and permits
The Info-Excavation request is free. The RBQ asks contractors to file it at least 4 business days before digging; it stays valid until the stated end date, 180 days at most. Hydro-Québec speaks of 72 hours, or three business days where a pipeline is involved: plan for the longer of the two.
In Quebec, the duty to locate lines before digging falls on the employer on a work site (construction safety code). For homeowners digging themselves, it is the basic precaution, and some municipalities require it in their bylaws. Depending on the project, a municipal permit may also be needed: retaining wall, pool, curb cut, parking, fill.
01File the Info-Excavation request[2, 5, 7, 8]
- File the request online at least 4 business days before digging starts. Count business days, not weekends or holidays.
- Give the address, the marked area, the type of work, the depth and the dates.
- Write down the request number, the list of network owners notified and the end date.
- If a network owner does not respond, or a network is not a member (some municipalities), contact it directly.
- If the work will outlast the validity, plan a new request before the end date.
Done when : You have a request number, the list of owners notified and the end date, at least 4 business days before you dig.
02Check the project's municipal permits[2, 9, 10, 11]
- Name the structure you are digging for: drain, patio, wall, pool, parking, curb cut, fill.
- Check your municipality's planning page or department, and in Montreal your borough's.
- For a pool, a municipal permit is always required. For a curb cut in Montreal, the City lowers the sidewalk, from May to October. Some cities have rules on fill.
- Gather the documents requested and keep the answer in writing.
Done when : You have a written answer from the municipality: permit issued, or confirmation that no permit is needed for this work.
Phase 3 · Excavation
Dig safely near the marks
Marks show where a line runs, not how deep: that is why it gets exposed by hand. Keep the machine at least 1 m from each side of the marks and expose the line by hand or by vacuum until you can see it.
Never go into a trench deeper than 1.2 m unless its walls are shored or sloped back. Keep soil and materials at least 1.2 m from the edge, and machines at least 3 m back.
01Check the marks before the first shovelful[2, 12, 13]
- Compare the list of owners notified with the marks or clearances received: there must be an answer from each one.
- Check that the marks cover the whole requested area.
- Photograph the marks with a fixed landmark (house, marker) in the picture.
- If a mark is missing or worn off, do not dig: call the network owner back.
Done when : Every owner notified has marked its lines or confirmed it has none, and the marks are photographed.
02Expose the lines by hand[1, 2, 12]
- Within the 1 m strip on each side of the marks, dig with a round shovel, gently, scraping rather than stabbing. No pick or digging bar.
- Keep going until you see the pipe or cable across the full width of the dig, and note its depth.
- If an exposed line crosses the trench, support it; do not let it hang and do not move it without its owner's consent.
- Only then may the machine dig outside the protected strip.
Done when : Every marked line crossing the dig is visible, supported and its depth is written down.
Safety : No pick or digging bar near a line. If you hit it, follow the "If you hit a line" step.
03Dig the rest of the excavation[2, 12, 14]
- Dig by machine outside the protected strip, to the planned depth.
- Place spoil at least 1.2 m from the edge. Keep machines at least 3 m from the edge unless the shoring is designed for them.
- If the dig is deeper than 1.2 m and someone has to go in, shore it (trench box or engineered shoring) or slope the walls at less than 45 degrees starting 1.2 m above the bottom.
- Keep the dig reasonably dry and a ladder on site if anyone goes in.
- Nobody under 18 works in a trench.
Done when : The dig has the planned depth and width, its walls hold without crumbling, spoil sits at least 1.2 m from the edge and no marked line was touched.
Safety : Never go into a trench deeper than 1.2 m unless its walls are shored or sloped back. Nobody stands within the bucket's reach.
04If you hit a line[1, 2, 5, 13]
- Stop the machine and move everyone away from the dig.
- If you smell gas, hear hissing or see a power cable exposed or torn, leave the area, keep everyone away and call 911.
- Call the network owner (contact details are on the locate confirmation) and report the damage, even if it looks minor: a scraped jacket or a dent counts.
- Do not repair anything yourself, do not touch the cable or pipe and do not backfill.
- Photograph the line and the marks and note the time.
Done when : If damage happens, the area is secured, the network owner is notified and nothing is backfilled before they come.
Safety : Never approach a torn cable and never try to stop a gas leak yourself.
Phase 4 · Base
Backfill around the lines
Backfill around an exposed line is done by hand, on a uniform bed, with no stones against the pipe or cable. A damaged line, even slightly, is never backfilled: its owner has to see it first.
01Inspect, then backfill by hand[1, 2, 15]
- Inspect every exposed line: cut jacket, dent, scrape. At the slightest doubt, call the owner before backfilling.
- Around and over the line, place a fine, uniform material (sand or fine stone) by hand, with no stones or debris against it, and compact lightly by hand.
- Once the line is well covered, backfill the rest in lifts and compact each lift.
- Do not run the plate compactor or the machine directly over a shallow line.
Done when : No damaged line was covered, backfill around the lines was placed by hand with no stones, and the rest is compacted in lifts.
Safety : Backfill by hand around the lines, with no machine. If a line, cable or gas pipe is touched, even slightly, stop, move everyone away and call the line owner before backfilling.
Phase 5 · Install and finish
After the work: soil, records and validity
Keep your request number with the photos of the marks and of the exposed lines: it shows you dug with care. If the work goes past the request's end date, file a new one before carrying on. Excavated soil takes more room than in the ground (swell): the calculator accounts for it in the trips. When you restore the ground, do not send water toward your neighbour.
01Deal with the spoil and file the records[2, 5, 16]
- Have surplus spoil hauled away or take it to a site that accepts it; drop-off depot rules vary between municipalities.
- Put the topsoil back and give the ground a slope that takes water away from buildings without sending it to the neighbour.
- File together the request number, the photos of the marks and the exposed lines, and the permits.
- If work resumes after the request's end date, file a new request before digging.
Done when : The spoil is gone or reused, the ground is restored without sending water to the neighbour and the records are filed.
Common mistakes
Starting before the lead time or before all answers are in[5]
What happens
A line that is not yet marked gets hit.
How to avoid it
File at least 4 business days ahead, and wait for every notified owner's answer.
Digging with the bucket on the marks[1]
What happens
The bucket tears the line before anyone sees it.
How to avoid it
No machine within 1 m on each side of the marks: expose by hand.
Assuming the request covers your private lines[7]
What happens
Wires and pipes laid by you or a previous owner are not marked and get cut.
How to avoid it
Make your own list and find your private lines before digging; contact directly any network that does not respond.
Letting the request expire[5]
What happens
The marks have faded or changed and you dig without current information.
How to avoid it
Note the end date (180 days at most) and file again before passing it.
Spoil and machine at the trench edge[12]
What happens
The weight collapses the wall onto whoever works at the bottom.
How to avoid it
Spoil and materials at least 1.2 m from the edge, machines at least 3 m back.
Going into a deep trench with vertical walls[12]
What happens
A collapse can bury and kill, even in soil that looks firm.
How to avoid it
Beyond 1.2 m, shore or slope the walls back before anyone goes in.
Backfilling over a scraped line[1]
What happens
The hidden damage causes a leak or an outage later, with nobody knowing where it comes from.
How to avoid it
Inspect every exposed line; at the slightest doubt, call its owner before backfilling.
Digging without knowing the property lines[3]
What happens
The structure encroaches on the neighbour or the setback and has to be redone.
How to avoid it
Check the certificate of location or hire a land surveyor before digging near a line.
When to call a pro or an engineer
- LocateApplies to the typical project
File a free Info-Excavation request at least 4 business days before you dig. Keep the machine at least 1 m from the marks.[1, 5]
- Contractor
Trench deeper than 1.2 m that someone enters: it needs shoring (rented trench box or engineered shoring) or sloped walls. Hire an equipped business.[12]
- Contractor
Excavation deeper than 3 m: barricades at least 0.7 m high or a warning line around it, on top of shoring. Professional work.[12]
- Engineer
Excavation near a neighbouring building's foundation: if it threatens its stability, underpinning or shoring to plans is required. Consult an engineer.[12]
- Contractor
High water table: the dig has to be kept reasonably dry (pumping) and the walls become unstable. Plan for an equipped business and a contingency.[12]
- Contractor
Rock expected: it takes a breaker and many more machine hours. Ask for a quote with a unit price for rock.[14, 17]
- Land surveyor
Work near a property line: confirm it with the certificate of location or a land surveyor.[3]
- Engineer
Land in a landslide zone: a geotechnical study is required before digging or filling.[18]
- Contractor
You are changing the ground level near a line: you may not make the flow toward your neighbour worse. Have the slopes and drainage checked.[16]
Rules in Quebec
- LocateAll of Quebec
Free Info-Excavation request before digging. The RBQ asks contractors to file at least 4 business days before the work; it is valid until its end date, 180 days at most, and damage is recorded in the contractor's file. Hydro-Québec speaks of 72 hours, or three business days where a pipeline is involved.[5, 8]
Checked October 10, 2026
- LicenceAll of Quebec
A contractor who digs for you works under an RBQ licence (excavation and earthwork subcategory); the RBQ ties the locate request and any damage to that licence file. Check the licence in the RBQ register before hiring. Digging yourself at home needs no licence, but the locate request is still required.[5, 19]
Checked October 10, 2026
- SafetyAll of Quebec
On a work site, the employer must find and exactly locate buried lines before digging. Trench walls must be shored, with exceptions (sound rock, nobody goes in, slope under 45 degrees starting 1.2 m from the bottom, an engineer's certificate). No materials within 1.2 m of the edge, no machine within 3 m, a ladder every 15 m, nobody under 18 in a trench. These rules bind employers; the danger is the same for a homeowner.[12]
Checked October 10, 2026
- LocateAll of Quebec
Keep machines at least 1 m on each side of the marks and expose lines by hand or vacuum. Never backfill over a damaged pipe or cable.[1]
Checked October 10, 2026
- Locatemagog
Magog requires by bylaw a locate request to dig on municipal land, at least 3 business days ahead.[20]
Checked October 10, 2026
- PermitAll of Quebec
A municipal permit is always required to build, install or replace a pool, and for any structure that gives or blocks access to it.[9]
Checked October 10, 2026
- Permitmontreal
- Permitsherbrooke
Sherbrooke covers fill in a separate technical sheet: check it before bringing in soil or raising the ground.[11]
Checked October 10, 2026
- NeighboursAll of Quebec
Lower land receives the natural flow of water from higher land, but the upper owner may not make the neighbour's situation worse (Civil Code of Quebec, art. 979).[16]
Checked October 10, 2026
Words used
Sources
- 1.
Fiche technique 34, Protéger les services publics souterrains · APSAM (Association paritaire pour la santé et la sécurité du travail, secteur affaires municipales)
Consulted October 10, 2026Source page
- For APSAM, any hole dug in the ground is digging under the safety code, including a post hole or a tree pit.
- APSAM asks to keep the machine at least 1 m on each side of the marks and to expose lines by hand or vacuum, never with the bucket.
- APSAM forbids backfilling over a damaged pipe or cable.
- Any hole dug in the ground counts as digging.
- 2.
Experience curve effects · Wikipedia
Consulted October 10, 2026Source page
- Wright's law links task time to the number of repetitions; published progress ratios range from 0.75 to 0.90.
- 3.
Haie, clôture, muret et mur de soutènement · Ville de Laval
Consulted October 10, 2026Source page
- Laval asks for a certificate of location prepared by a land surveyor with a retaining wall certificate application.
- Land surveyor's certificate of location required with the certificate application.
- Land surveyor's certificate of location.
- 4.
Obtenir un permis pour aménager ou modifier un espace de stationnement · Ville de Montréal
Consulted October 10, 2026Source page
- Montreal asks for a certificate of location, photos, a plan and a detailed cost estimate for a parking permit.
- Montreal parking permit.
- 5.
Travaux d'excavation · Régie du bâtiment du Québec
Consulted October 10, 2026Source page
- The RBQ asks for the request at least 4 business days before the work; it is valid until its end date, 180 days at most.
- The RBQ asks for the Info-Excavation request at least 4 business days before the work; it is free, valid until its end date, 180 days at most, and damage is recorded in the contractor's file.
- The RBQ records damage in the contractor's file and can sanction its licence.
- The request is valid until its stated end date, 180 days at most.
- 6.
DTNI-3C, Mise en oeuvre des pavés et des dalles en béton ou en pierre naturelle sur lit de pose granulaire · Ville de Montréal
Published October 3, 2024Consulted October 10, 2026Source page
- Montreal forbids placing frozen aggregates. (s. 7.4.3)
- 7.
Demande de localisation · Info-Excavation
Consulted October 10, 2026Source page
- Info-Excavation takes locate requests online.
- Info-Excavation forwards the request to its member network owners.
- 8.
What to do before you dig (underground lines) · Hydro-Québec
Consulted October 10, 2026Source page
- Hydro-Québec asks for the request 72 hours ahead, three business days where a pipeline is involved, free of charge.
- Hydro-Québec before-you-dig page.
- Steps before digging.
- 9.
Règlement sur la sécurité des piscines résidentielles, RLRQ c. S-3.1.02, r. 1 · Gouvernement du Québec (LégisQuébec)
Consulted October 10, 2026Source page
- The provincial regulation requires a municipal permit to build, install or replace a pool. (art. 9)
- Residential pool safety regulation. (art. 9)
- 10.
Obtenir un permis pour aménager une entrée charretière · Ville de Montréal
Consulted October 10, 2026Source page
- In Montreal, the City lowers or rebuilds the sidewalk for a curb cut, May to October, after the permit.
- Montreal curb cut permit.
- 11.
Fiche technique no 15 : Remblai · Ville de Sherbrooke
Consulted October 10, 2026Source page
- Sherbrooke publishes a separate technical sheet for fill.
- Sherbrooke technical sheet 15.
- 12.
Code de sécurité pour les travaux de construction, RLRQ c. S-2.1, r. 4 · Gouvernement du Québec (LégisQuébec)
Consulted October 10, 2026Source page
- The safety code requires the employer to find buried lines in the area and locate them exactly on the ground before digging. (art. 3.15.1)
- The safety code allows a line to be disconnected, moved or left in place only with its owner's prior approval and temporary supports. (art. 3.15.1)
- The safety code requires shoring of walls except in sound rock, when nobody goes in, with a slope under 45 degrees starting 1.2 m from the bottom, or on an engineer's certificate; no materials within 1.2 m of the edge, no machines within 3 m. (art. 3.15.3)
- The safety code requires a ladder every 15 m of trench and bars people under 18 from trench work. (art. 3.15.4, 3.15.10)
- 13.
Prévenir les dommages aux infrastructures souterraines · COMBEQ
Published April 28, 2026Consulted October 10, 2026Source page
- COMBEQ reports that 31% of 2025 damage happened without a locate request.
- 14.
Guide des prix d'excavation : tout ce qu'il faut savoir · Soumission Rénovation
Published May 7, 2026Consulted October 10, 2026Source page
- Soumission Rénovation gives 4 to 6 mini excavator hours for 100 linear feet of trench 2 to 3 feet deep.
- Soumission Rénovation gives 12 to 18 breaker hours for 500 ft2 of rocky ground.
- 15.
Installation guide, Walls and design charts · Techo-Bloc (hosted by dealer Stonewood Products)
Consulted October 10, 2026Source page
- Techo-Bloc backfills and compacts in lifts of 200 mm or less.
- 16.
Écoulement des eaux (rapports de voisinage) · Gouvernement du Québec
Consulted October 10, 2026Source page
- The owner of the higher land may not make the natural flow onto the lower land worse. (C.c.Q. art. 979)
- Summary of Civil Code article 979. (C.c.Q. art. 979)
- Quebec government summary. (C.c.Q. art. 979)
- 17.
Code civil du Québec, RLRQ c. CCQ-1991 · LégisQuébec, Éditeur officiel du Québec
Consulted October 10, 2026Source page
- An estimated price may only rise for unforeseeable, justified work. (art. 2107)
- 18.
Formulaire de demande de certificat : Mur de soutènement (C-04) · Ville de Terrebonne
Published January 21, 2026Consulted October 10, 2026Source page
- Terrebonne requires a geotechnical study in a landslide zone.
- 19.
Vérifier la licence d'un entrepreneur · Régie du bâtiment du Québec
Consulted October 10, 2026Source page
- The RBQ explains how to check a contractor's licence.
- 20.
Demande de localisation Info-Excavation · Ville de Magog
Consulted October 10, 2026Source page
- Magog page on locate requests.
Review and history
- Status
- Draft awaiting review
- Last reviewed
- October 10, 2026
- Next review due
- April 10, 2027
- Reviewers
- Rédaction paysagement (editor)
Change log
- October 10, 2026
First version, written from the RBQ and Hydro-Québec pages, APSAM sheet 34 and the construction safety code. Draft awaiting legal and field review.