How Much Does a French Drain Cost in the Houston Area?

National cost guides put a yard French drain at about $10 to $35 per linear foot, installed. On those numbers, a 50-foot side yard run comes to about $500 to $1,800. A 100-foot run comes to about $1,000 to $3,500.

These are market numbers, not our price list. Around Houston, heavy clay and tight side yards can push a job up the range. If your yard holds water after a rain, our French drain installation page shows how we work around Katy, Texas.

What do cost guides say a French drain costs per foot?

One national guide, updated in February 2026, prices French drains by type:

Two other national guides set the per-foot range a little differently. One, updated in October 2026, lists $10 to $65 per foot for exterior drains. The other puts a yard drain at $20 to $30 per foot.

You may also see a national average near $5,000. That figure mixes in basement drains, the costliest kind. For a yard drain, length sets most of the total, as the first guide’s table shows:

What drives the price of a French drain?

Labor makes up most of the bill, all three guides say. So anything that adds digging time moves the price.

Length and depth

Every foot of trench needs digging and fill. Guides put most yard drains at 12 to 24 inches deep and about a foot wide. A deeper trench takes longer to dig and more rock to fill.

The pipe and the rock

A French drain is perforated pipe in a trench of washed rock, often wrapped in filter fabric. One guide lists drain pipe at $1 to $5 or more per foot. Washed rock runs about $1 to $3 per foot. The same guide says a 3- to 4-inch pipe suits most homes.

Downspout tie-ins

Downspouts that empty beside the house can keep a side yard soaked. One guide prices a buried downspout line at about $150 to $350 per downspout. Ask whether each downspout runs in its own solid pipe or ties into the French drain.

Access between close-set houses

Where houses sit close together, the side yard is a narrow strip behind a gate. Mowers and foot traffic pack that soil, and water holds there. Guides say tight access raises labor. When a trencher or small excavator cannot reach, the trench gets dug by hand.

The lawn and the dug soil

A trench leaves a strip of torn lawn and a pile of dirt. Guides count lawn repair as added labor and materials. One notes that reusing the dug soil in the yard cuts disposal fees.

Permits

Inside city limits, the city’s permit office decides. Outside them, the county does. Guides list permit fees from about $50 to $375 where one applies.

Katy’s city code requires a permit before a drain pipe goes into a city ditch or right of way. Sugar Land’s homeowner permit guide lists area drains under plumbing permits. In unincorporated Fort Bend County, the county lists regrading and drainage changes as work that needs a development permit.

How do Houston-area clay and flat ground change a French drain?

Federal climate records put the normal yearly rainfall at the Katy station at 49.1 inches. Every month averages more than 2.5 inches, and May is the wettest at about 5 inches.

The ground takes that water slowly. Lake Charles clay is extensive on the coastal prairie between the Colorado and Trinity Rivers, says the federal soil survey. The survey rates it very slowly permeable. Water soaks in fast while the clay is cracked and very slowly once the cracks close.

Bernard soils were first described in Fort Bend County. In winter and early spring, they stay saturated within 2 feet of the surface. Clay is slow to dig, and one guide lists it as a price factor.

Flat ground matters even more. Guides call for at least 1 percent fall, or 1 foot of drop for every 100 feet of drain. The soil survey describes these prairie soils as mostly under 1 percent slope. On a flat lot, the trench gets its fall by running deeper toward the outlet, and that means more digging.

The finish at the top matters in clay too. One guide warns that dirt over a French drain slows it and may stop it in some soils. Ask how the top of the trench is finished and whether a catch basin sits at the low spot.

When is a French drain the wrong fix?

Some wet yards need a different fix first.

• The yard slopes toward the house. The residential code for Texas cities calls for at least 6 inches of fall within 10 feet. Where a yard runs the wrong way, grading and dirt work come first. One guide prices regrading a yard at $500 to $5,000.
• Lot lines leave no room for that fall. Where lot lines block it, the same code calls for drains or swales. That is where a French drain fits.
• One downspout floods one corner. A buried downspout line may fix it alone.
• Water shows up inside the house. That calls for a plumber or a foundation contractor before any yard drain.
• There is no lower outlet. A drain needs somewhere lower to send water. One guide says dry wells suit sandy soil with a low water table, the opposite of wet clay. Some yards end up needing a pump, which is a separate job.
• The ditch or the culvert is backed up. On acreage, a silted ditch or a crushed driveway culvert can hold water in a yard. Opening that up may be the real fix.

What should a written quote for a French drain cover?

A written quote should name:

• the route and the length in feet
• the trench depth and the fall to the outlet
• the pipe size and the rock around it
• whether fabric wraps the rock
• where the water exits, and whether that spot sits lower than the wet area
• each downspout tie-in and how it is piped
• what happens to the dug soil and the lawn
• who files the Texas 811 locate request before digging starts
• any permit the city or the county asks for

Two quotes with the same total can cover very different work. The line items show the difference.

How do you get a French drain priced around Katy?

We put in French drains across Katy, Texas and the west side of Houston. We also run gutter downspout lines underground and backfill washouts with crushed granite. We look at where the water sits and where it can go, then put the quote in writing. See how we install French drains, or call or text (979) 824-2296.