What a French drain actually does
An exterior French drain is a gravel trench with a perforated pipe. Water already in the soil can move into the stone, enter the pipe, and travel to an outlet.
That is subsurface drainage. It is for saturated ground: a lawn that stays spongy, a low area that stays wet underfoot, groundwater that keeps reappearing in the same place.
It is not a grate. It does not scoop a puddle off the surface as fast as a catch basin. If the outlet is wrong, collected water has nowhere honest to go.
What grading actually does
Grading changes slope so surface water runs a better direction. A swale is a shallow drainage path in the lawn — a gentle channel, not a ditch — that gives that water a route.
That is surface-water work. It is for runoff that is traveling the wrong way, a bowl that ponds, a yard that tilts toward the house, a side strip that acts like a trough.
Grading will not drain soil the way a French drain does. It can keep new surface water from pouring into the area a French drain is trying to relieve.
Visible surface runoff vs. saturated soil
If you can watch water sheet across the lawn, pond in a dish, or run toward the house, start with the shape of the ground. A trench under a reverse slope still has to fight incoming surface water.
If the lawn is spongy with little or no puddle, and water seems to well up rather than collect, the soil is holding water. A grade change alone may leave that saturation in place.
Low areas can be both: a bowl on top and wet soil underneath. Then the honest plan is often grade or a swale for the surface, and a French drain for what still soaks in — if there is a working outlet for both.
When one is usually the better first conversation
Grading (or a swale) is usually the better first conversation when the problem is direction: water crossing the yard, a dish that fills from above, slope toward the house, a missing path for runoff.
A French drain is usually the better first conversation when the problem is storage in the soil: the surface looks drained and the ground is still soft days later.
There is no universal winner. A French drain in the wrong place, or grading that fills a hole without an exit, both fail for the same reason: the water still has nowhere to leave.
When they work together
Many yards need both. Reshape the surface so rain runs to a swale or a basin. Use a French drain where the ground remains saturated after that surface water is no longer trapped.
Downspouts dumped onto a reverse slope will keep wetting the same strip until either the discharge point or the grade changes. Pipe under that mess without moving the roof water is a common way to overbuild the wrong layer.
Yard drainage is the broader decision: where the water starts, how it should travel, and where it can discharge. French drain vs. grading is one slice of that decision, not the whole menu.
What to look at before choosing
- Whether the water you care about is on the surface or in the soil
- The direction of slope toward or away from the house
- Low bowls vs. broad saturation
- Downspout discharge feeding the same area
- A realistic outlet for a trench, a swale, or both
Read the service pages next
These pages explain each method without treating it as the answer to every wet yard.