How much does trenching cost per foot?
Ashburn, VA

How much does trenching cost per foot?

Ashburn, VA

How much does trenching cost per foot?

$5 – $12cost per linear foot
$500 – $1,200total cost to dig a 100’ trench

Get free estimates for your project or view our cost guide below:

$5 – $12 cost per linear foot

$500 – $1,200 total cost to dig a 100’ trench

Get free estimates for your project or view our cost guide below:
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Kristen Cramer
Written by
Kristen Cramer
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Trenching cost

Trenching costs $5 to $12 per linear foot, depending on the length, depth, soil type, and obstructions. Digging a 100-foot trench costs $500 to $1,200 on average for underground electrical conduit or water, sewer, or gas lines. Trenching services charge $35 to $65 per hour for labor.

Trenching cost
Trench length Average cost
1’ $5 – $12
10’ $50 – $120
25’ $125 – $300
50’ $250 – $600 
100’ $500 – $1,200
125’ $625 – $1,500
150’ $750 – $1,800
200’ $1,000 – $2,400

Get free estimates from excavating companies near you.

Average cost to dig a trench per foot

The following table shows the average trenching cost per linear foot.

Trenching cost calculator per foot
Factor Average cost per linear foot
Equipment / trencher $2 – $3
Labor cost $3 – $9
Total cost $5 – $12

Cost to dig a trench by project

Trenching cost by project
Project type Cost per linear foot installed Total cost installed*
Drainage system $10 – $30 $1,000 – $4,000
Electrical panel $6 – $14 $850 – $2,500
Gas line $12 – $25 $350 – $1,000+
Retaining wall $40 – $300 $4,000 – $10,000
Sewer line $40 – $180 $1,600 – $7,200
Water lines $30 – $50 $800 – $3,000
Foundation $5 – $30 per square foot $5,100 – $19,300

*For the complete project including trenching.

Underground conduit installation cost per foot

Installing an underground conduit costs $5.50 to $25.00 per linear foot, depending on the utility and conduit type. Trenching and installing PVC or polyethylene pipe is typically the cheapest, while running copper or steel pipes for water or natural gas lines costs the most.

Underground conduit installation cost
Line type Material price per linear foot Total cost per foot installed Uses
½ inch non-metallic PVC conduit $0.90 – $1.50 $6.00 – $13.50 Electrical wiring 
Copper pipe (Type K) $6.00 – $11.00 $11.00 – $23.00 Water line
4-inch PVC pipe $1.30 – $3.00 $6.30 – $15.00 Sewer or drain line
1-inch polyethylene pipe $0.50 – $0.80 $5.50 – $12.80 Irrigation or gas line
2-inch black steel pipe $7.00 – $15.00 $12.00 – $25.00 Natural gas line

Professional digging a trench for electrical conduit with a mini-excavator.
Professional digging a trench for electrical conduit with a mini-excavator.

Electrical trenching cost

Electricians charge $50 to $130 per hour on average. Installing underground electrical wiring requires trenching but minimizes the chance of a power outage during a storm. Electrical trenching for underground service typically costs more in densely populated urban areas.

Other home electrical projects may require trenching:

  • The cost to replace an electrical panel is $850 to $2,500, depending on the amperage, and may require trenching to run new conduit if upgrading to a higher amp panel.

  • New electrical wiring for a hot tub installation costs $800 to $1,600, including a new circuit and outlet.

  • A wired home security system costs $199 to $900 for equipment and installation with $25 to $50 monthly monitoring fees on average.

  • A home generator costs $6,000 to $11,000 installed. Whole-home standby generators are typically powered by natural gas or propane and require trenching to run a new gas line and electrical conduit.

Cost to trench a water line

Replacing a water main costs $30 to $50 per linear foot or $800 to $2,000 on average, depending on the type of pipe used and the distance from the home to a well pump or city water supply. Trenching a new water line costs $1,700 to $3,000, including connecting the system to the meter.

Other plumbing projects that require trenching include:

Cost to trench a sewer line

Sewer line installation costs $40 to $180 per linear foot or $1,600 to $7,200 on average, including labor, materials, and trenching up to 40 feet from the home to a septic tank or public sewer system.

Other sewer and septic system projects often require trenching:

Cost of digging a drainage system

An interior or exterior perimeter drain tile costs $4,000 to $15,000 installed. A French drain costs $1,000 to $4,000, including trenching labor and materials. Drainage issues are one of the most common reasons for trenching around a home or yard.

Other methods of protecting the home from water damage include:

  • Basement waterproofing costs $4,500 to $15,000 on average or $6 to $15 per square foot. Excavators carefully trench around the foundation to expose the basement’s exterior walls for waterproofing.

  • A retaining wall costs $40 to $300 per linear foot installed, depending on the wall height and material.

Gas line trenching cost

Gas line installation costs $12 to $25 per linear foot on average, depending on the complexity, type of pipe, and distance from the main gas supply. Trenching costs increase if the new gas line crosses a driveway, sidewalk, or other obstacles.

Foundation trenching cost

Foundation excavation costs $1,500 to $10,000 on average to create a foundation pad or dig a basement for a new home site. Excavating a large foundation or in areas with rocky soil costs $20,000+.

Geothermal heat pump trenching cost

A geothermal heat pump costs $15,000 to $35,000 on average installed, depending on the system type and size. Installing a horizontal closed-loop geothermal system requires trenching to bury the loops 4 to 10 feet below the surface.

Trenching cost factors

The following factors affect the cost of digging a trench:

  • Trench length and depth – Most residential trenches are less than 5 feet deep. A trench that is 5 feet deep or greater requires shoring or a protective system to prevent the sides from collapsing onto workers.

  • Soil type and conditions – Trenching costs less in areas with soft, loose soil and more in hard clay or rocky soil.

  • Equipment – Hand-digging with a shovel takes longer and increases labor costs. Digging with a mechanical trencher or mini excavator takes far less time but increases equipment costs.

  • Labor – Trenching labor costs $35 to $65 per hour on average, not including materials or other services. Landscapers charge $50 to $100 per hour for trenching to add drainage or irrigation systems.

  • Materials – Trenching contractors typically include the cost of utility line flags, plywood for shoring trench walls, and hand-trenching shovels or hoes in their estimate.

  • BackfillingFill dirt costs $5 to $25 per cubic yard or $4 to $15 per ton delivered. Confirm your estimate includes any required fill dirt or backfill materials, along with delivery fees.

  • Permit ­– Permits for earthwork cost $50 to $400, depending on location.

  • Obstructions – Trenching costs increase if the diggers encounter obstructions on or below the surface.

Boring vs. trenching costs

Get free estimates from excavating companies near you.

Horizontal or directional boring costs $10 to $30 per linear foot. Directional boring is less invasive to the terrain above a project area, allowing contractors to drill an underground borehole beneath obstacles like concrete or pavement without damaging the surface.

Trenching FAQs

How long does it take to dig a trench?

Trenching 100 feet takes 2 to 3 hours on average with a mechanical trencher or up to 10 to 12 hours if digging with a shovel, depending on the depth, soil type, obstructions encountered, and if backfilling is included. Trenching in hard clay or rocky soil takes longer.

Do you need a permit to dig a trench?

Digging a trench requires a permit in some cities. Call 811, the national call-before-you-dig number, or visit the Common Ground Alliance website to check local regulations before digging.

Do electricians dig trenches?

Most electricians do not dig trenches themselves but subcontract laborers who handle the trenching for electrical conduit.

How deep are trenches?

Residential trenches are 12” to 24” deep on average, depending on the purpose:

  • Electrical wire must be buried at least 12” deep if housed in a rigid non-metallic conduit and 18” deep if housed in a weatherproof casing.

  • Gas lines must be buried at least 24” deep in most locations. Some states require a 30” minimum depth instead.

  • Water lines must be at least 12” below the local frost depth and no less than 2 feet underground. The frost depth varies from as little as 6” to over 72”, depending on the geographic location.

The U.S. Occupational Safety and Health Administration (OSHA) mandates that trenches 5 feet deep or greater require a protective system of shoring or sloped walls to prevent the dirt from collapsing on workers.

Getting estimates from trenching services

Before hiring a trenching company near you, be sure to:

  • Get at least three estimates to compare.

  • Read their reviews on HomeGuide and Google.

  • Select licensed, bonded, insured companies that have been in business for 5+ years.

  • Ask for recent references.

  • Avoid selecting the lowest quote as quality may suffer.

  • Get a detailed written estimate, contract, and warranty in writing before paying a deposit.

  • Never pay in full up front. Use a payment plan instead.

Questions to ask

  • How long have you been in business?

  • Are you licensed and insured?

  • Have you worked on similar projects?

  • Can you provide references from recent projects?

  • Will you handle the project yourself or subcontract it to someone else?

  • Do you own or rent the trencher or excavating equipment? Does the estimate include all equipment and delivery fees?

  • How deep and wide will you be trenching?

  • How will you keep my pipes and buried utility lines safe?

  • What will you do with the excavated dirt?

  • Will my project require additional fill dirt? If so, how much will it cost?

  • Does the estimate include site cleanup?

  • Are there any additional fees for transporting or dumping debris?

  • Will you pull the necessary permits?

  • How long will the project take?