French drain cost
A 50 ft French drain costs about $1,000 to $2,500 installed, at the $20 to $50 or more a foot the University of Georgia gives, or about $278.12 in stone, pipe and fabric if you dig it yourself.
What the price per foot covers
The University of Georgia's green stormwater demonstration site puts a residential French drain at $20 to $50 or more a linear foot, with materials and labor. That covers digging the trench, lining it with fabric, the stone and perforated pipe, and putting the soil or sod back. The low end is a short, shallow run in open, easy ground; the high end and beyond is a deep trench, a long way to the outlet, tree roots, rock, or a yard a machine can't reach.
| Length | At $20 a foot | At $35 | At $50 |
|---|---|---|---|
| 20 ft | $400 | $700 | $1,000 |
| 30 ft | $600 | $1,050 | $1,500 |
| 50 ft | $1,000 | $1,750 | $2,500 |
| 75 ft | $1,500 | $2,625 | $3,750 |
| 100 ft | $2,000 | $3,500 | $5,000 |
| 150 ft | $3,000 | $5,250 | $7,500 |
What public jobs paid in 2025
State highway departments publish what they pay for underdrains, the road builder's French drain. These are averages for 2025, per linear foot. Underdrains, as each state specifies them, ran $38 to $57 a foot. Where the pipe is paid on its own, the stone is a separate item: West Virginia paid $95 a cubic yard for it. Highway crews install them by the thousand feet with machines already on site, so a homeowner's single drain usually costs more per foot.
| State | Item | Per foot | Quantity |
|---|---|---|---|
| South Dakota | 4 in underdrain pipe | $38.17 | 12,278 ft, 17 contracts |
| West Virginia | Aggregate-filled fabric underdrain | $49.32 | 483 ft, 2 contracts |
| Florida | Underdrain, Type II | $57.12 | 3,292 ft, 4 contracts |
| Florida | Underdrain, Type I | $45.00 | 1,343 ft, 1 contract |
| West Virginia | 4 in underdrain pipe (stone paid separately) | $21.82 | 1,230 ft, 4 contracts |
| Wisconsin | 6 in pipe underdrain (stone paid separately) | $16.00 | FY 2025 |
Doing it yourself
The materials for a 50 ft drain, 12 in wide and 18 in deep, come to about $278.12: roughly 3 tons of washed stone at 2025 yard prices, five 10 ft lengths of perforated pipe and a strip of filter fabric. The French drain calculator works it out for your trench. The work is in the digging: a 50 ft trench of that size is almost 3 cubic yards of soil, so many people rent a trencher for the day.
What adds to the price
A solid pipe from the end of the drain to the outlet, a catch basin where a downspout joins, a pop-up emitter at the outlet, or a sump pump where there's no lower ground all cost extra. Florida paid $61.77 a foot for 4 in underdrain outlet pipe in 2025. Ask contractors to quote the same depth, width, pipe and outlet so the prices compare, and for stone prices on their own, see gravel prices.
Sources
- Stop 2: French drain, University of Georgia, Green Stormwater Infrastructure demonstration site, read November 2026. An 18 × 18 in trench, a 4 in pipe 3 in above the bottom, nonwoven geotextile, at least 1% slope; $20 to $50 or more a linear foot with materials and labor.
- 2025 bid item price report, South Dakota Department of Transportation, 2025 lettings. Average low bid for Class A, B and C riprap: $43.93, $70.54 and $83.00 a ton; 4 in underdrain pipe $38.17 a foot; base course $22.00 and gravel surfacing $43.77 a ton; contractor-furnished borrow $13.69 a cubic yard; sodding $4.62 a square yard; 4 in shredded bark mulch $5.78 a square yard.
- 2025 average unit bid prices, West Virginia Division of Highways, 2025 lettings. Statewide weighted averages: MSE modular block retaining wall $182.10 a sq ft of face; riprap $151.96 a cubic yard; aggregate-filled fabric underdrain $49.32 a foot; unclassified borrow excavation $45.27 a cubic yard.
- Historical item average costs, statewide, 2025, Florida Department of Transportation, 2025 lettings. Rubble riprap, furnished and installed: ditch lining $123.96 a ton, bank and shore $143.61 a ton; underdrain Type II $57.12 a foot; borrow excavation $36.23 a cubic yard; performance turf, sod $4.51 a square yard; retaining wall system, permanent, $63.81 a sq ft of face.
- Average unit price list, FY 2023 to FY 2025, Wisconsin Department of Transportation, FY 2025. FY 2025: riprap light, medium and heavy $134.48, $112.90 and $67.23 a cubic yard; 6 in pipe underdrain $16.00 a foot; base aggregate dense ¾ in $22.56 a ton; borrow $7.39 and select borrow $16.47 a cubic yard; sod lawn $8.18 a square yard.
- Infiltration: French drains, trenches and dry wells, City of Norfolk, Virginia, read November 2026. A trench at least 12 in wide and 18 to 24 in deep; slope 1 in every 8 ft; 2 to 3 in of gravel under the pipe, gravel to 3 to 5 in below the top; fabric overlapped at least 12 in.