French drains and yard drainage
French drain installation in Chattanooga, TN
French drains, catch basins, underground downspout lines and regrading for soggy Chattanooga yards and wet crawlspaces. Most French drains here run about $20 to $50 per foot installed. Get a free written quote after a site visit.
Signs
Does your yard need drainage?
If any of these sound familiar after a normal Chattanooga storm, water is not leaving the property the way it should.
Grass that stays soggy for days
Dense clay holds water at the surface. Mud, moss and dead patches in the same spot every spring.
Water at the foundation or in the crawlspace
Downspouts dumping next to the house, or a ridge side yard that drains straight toward it.
Washouts below a slope or wall
Clay streaks across the patio or driveway, gullies in the lawn, or soil washing out at the base of a retaining wall.
01
French drains
A trench lined with filter fabric, filled with washed stone around a perforated pipe, sloped to an outlet. Shallow yard drains are usually 18 to 24 inches deep. Footing drains along a foundation go deeper and cost more, and rock in the trench line adds time.
- French drainPer linear foot, installed$20 to $50 / ft
- Typical French drain projectMost homeowners$2,000 to $7,000
- Trench drainDriveways and patios$30 to $70 / ft
Source: Angi yard drainage cost (2026). Typical ranges, not quotes.
02
Yard drainage: catch basins and dry wells
For water running across the surface, a catch basin at the low spot collects it and a pipe carries it off. Where there is no downhill outlet and the ground is not prone to sinkholes, a dry well lets it soak in slowly underground.
- Yard drainage projectMost homeowners, all types$2,147 to $7,176
- Catch basinPer installed unit$600 to $2,000
- Dry wellPer installed unit$1,000 to $4,000
Source: Angi yard drainage cost (2026). Angi's 2026 national average for yard drainage is $4,634.
03
Underground downspout drainage
Each downspout can put hundreds of gallons next to the foundation in one storm. Burying solid pipe from each downspout to an outlet away from the house is one of the simplest fixes for a wet crawlspace or basement.
- One underground extensionSingle downspout$800 to $2,000
- Two extensionsMost common setup$1,200 to $2,200
- Full underground gutter drainageWhole house$1,500 to $7,000
Source: Angi underground gutter drainage cost (2026). Typical ranges, not quotes.
04
Grading and swales
Sometimes the fix is the shape of the ground. Regrading so soil falls away from the house, or cutting a shallow grassed swale to steer ridge runoff around it, can beat a buried system on cost.
- Land gradingTypical project$900 to $3,000
- SwalePer linear foot$5 to $15 / ft
Sources: Angi retaining wall cost (2026); Angi yard drainage cost (2026).
Holding back a slope too? See retaining walls.
FAQ
French drain and drainage questions
How much does a French drain cost in Chattanooga?
Angi's 2026 data puts French drains at about $20 to $50 per linear foot installed, with most projects between $2,000 and $7,000. A 100 foot shallow yard drain often lands between $2,000 and $5,000. Deep drains along a foundation, rock in the trench, and long runs to an outlet cost more.
What is the difference between a French drain and a surface drain?
A French drain is a gravel filled trench with a perforated pipe that collects water soaking through the soil. A surface drain or catch basin collects water running across the top of the ground, like a low spot at the bottom of a ridge side yard. Many Chattanooga yards need a little of both.
Where does the water go?
Downhill to a daylight outlet, a pop up emitter, a dry well, or the street where local rules allow it. A drain is only as good as its outlet, so the outlet is planned before any trench is dug.
Will a French drain work in Chattanooga clay?
Yes, and clay is the reason most yards here need one. Water moves slowly through dense clay, so it sits on the surface or against the foundation. A gravel trench gives it an easy path out. Filter fabric keeps the clay from clogging the stone.
Can I use a dry well if my yard has sinkholes?
Parts of the Chattanooga valley sit on limestone, where sinkholes can form. Dumping concentrated water into the ground near a sinkhole or a foundation is not a good idea, so on those lots the plan usually sends water to a surface outlet instead. The site visit is where that gets decided.
Can my downspouts be piped underground?
Yes. Angi's 2026 data puts one underground downspout extension at about $800 to $2,000, and full underground gutter drainage at $1,500 to $7,000 depending on how many downspouts and how far the water has to go.
Does grading fix standing water?
Sometimes. If the yard slopes toward the house, regrading so the ground falls away from the foundation can be the cheapest fix. Angi's 2026 data puts land grading at about $900 to $3,000.
Get a free French drain quote
Tell us where the water sits and where it comes from. A local crew follows up with a written plan and price.