Catch Basin vs. French Drain: Which Does Your Lot Need?

The Most Common Drainage Decision

If your yard has a water problem, odds are someone has suggested either a catch basin or a French drain. They're the two workhorses of residential drainage, and they're easy to confuse because both end in a pipe carrying water away. But they collect water in completely different ways, and picking the wrong one is the fastest path to a drain that doesn't fix anything.

The decision comes down to a single question: is your water sitting on the surface, or soaked into the soil? This guide answers it. For the full menu of drainage systems, see our Oregon drainage guide.

What a Catch Basin Does

A catch basin is a box sunk into the ground with a grate on top, set at a low spot where water collects. Surface water flows across the ground, reaches the basin, drops through the grate, and exits through a pipe to your outfall. It's point collection — it grabs water that pools in one specific place.

Catch basins excel where water visibly puddles: the sag in a driveway, the low corner of a lawn, the dip in a parking lot. As a bonus, the basin's sump traps sediment and debris before they reach the pipe, which is why basins need periodic cleaning. For pricing, see our catch basin installation cost guide.

A catch basin only works if surface water can actually reach it. If your problem is soggy ground rather than visible puddles, a basin sits there dry.

What a French Drain Does

A French drain is a gravel-filled trench with a perforated pipe at the bottom, wrapped in filter fabric. Instead of collecting water at one point, it collects it along its entire length. Water in the surrounding soil seeps into the gravel, drops into the perforated pipe, and flows to the outfall.

French drains shine when the ground itself is saturated — a lawn that stays spongy, a slope seeping water downhill, a wet area with no obvious puddle. They're line collection, not point collection. See our French drain cost in Oregon guide for budgeting.

The Oregon catch: in dense clay, water migrates so slowly that it may never reach the buried pipe fast enough to help. On heavy clay, a French drain often needs surface help to actually solve the problem.

Surface vs. Subsurface, Side by Side

How to Tell Which You Need

Walk your yard during or right after a hard rain and look closely:

• Water pools visibly in one or two spots, then sits there → catch basin. It's surface water with a clear low point to capture.
• The whole area is squishy and saturated, with no single puddle → French drain. It's subsurface water spread through the soil.
• Water runs down a slope and collects at the bottom → often a French drain across the slope to intercept it, sometimes paired with a basin at the low point.
• A patio or driveway holds shallow puddles → a catch basin or a smaller area drain.

When You Need Both

Plenty of Oregon properties have surface and subsurface problems at the same time. A typical combined setup uses a French drain to relieve saturated ground and a catch basin to capture surface ponding, both tied into one outfall. The two complement each other: the basin handles the visible puddle, the French drain handles the soggy ground around it. Our yard drainage cost guide shows how a combined system affects budget.

The Detail Both Systems Share

Whichever you choose, the outfall makes or breaks it. Both a catch basin and a French drain need somewhere lower to send their water — daylighted onto a slope, into a dry well, or to a permitted storm connection. And both need adequate slope on the outflow pipe to keep water moving. A perfectly built basin or drain with nowhere to go just backs up.