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A French drain moves water from one place to another. If there is no lower place for the water to go, the drain just relocates the problem.
A French drain moves water from one place to another. That sentence contains everything you need to evaluate whether one will solve your problem. If you have a clear, legal place for the water to go — a ditch at the road, a swale at lower elevation, a storm drain at the curb — a French drain is often the right tool. If you do not, installing one just relocates the wet spot rather than eliminating it.
The team at Beaverton Excavation Co. turns down French drain jobs occasionally — not because the work is difficult, but because the site does not have a workable outlet and installing pipe would leave the homeowner with the same problem in a different location. Before deciding on any drainage approach, the first question to answer is: where does the water ultimately need to go?
A French drain is a transport mechanism, not a destination. Perforated pipe collects groundwater or surface runoff along its length and carries it — by gravity — to a discharge point. The pipe itself does not absorb water. It does not evaporate water. It does not store water. It moves water.
On a property with no accessible outlet lower than the problem area, a French drain cannot function as intended. The pipe fills, backs up, and the saturated ground around it stays saturated. Some contractors will install the pipe anyway and never mention this limitation. Others will propose a dry well or a sump pump to compensate — sometimes that is the right call, and sometimes it is an expensive workaround for a problem that has a cheaper solution.
Washington County's flat valley floor creates this situation regularly. Beaverton sits at an elevation where neighboring properties, streets, and drainage swales are often at nearly the same grade. When everything around you is flat, finding a meaningful elevation drop for a gravity outlet is not always possible, and the French drain recommendation may be the wrong starting point.
Many residential wet-yard problems in Washington County are not groundwater problems — they are grading problems. The ground around the house has settled over the years, reversed slope toward the foundation, or developed a low bowl that collects roof runoff and rainwater. In these cases, the fix is moving dirt, not installing pipe.
A proper regrade reshapes the surface so water sheds away from structures and toward the street, a side yard, or a natural swale. It costs less than a French drain in most cases, requires no ongoing maintenance, and addresses the cause rather than the symptom. It also tends to be less disruptive — no trench, no pipe, no aggregate to haul in.
The diagnostic question is whether the water is staying in the yard because the ground cannot absorb it fast enough (a drainage capacity problem), or because the surface directs it to a low point (a grading problem). Standing water that appears in the same bowl every winter but drains away on its own within 24 to 48 hours of dry weather often indicates a grading issue, not a soil or groundwater issue. Grading and leveling work is frequently the cheaper and more durable solution.
A dry well is an underground chamber — typically a perforated precast concrete cylinder or a prefab plastic unit — that stores water temporarily while it percolates into the surrounding soil. It is appropriate when you have a defined volume of water arriving at a specific point (typically a downspout) and the soil at depth drains better than the surface. On Tualatin Valley clay, percolation rates are low, so dry wells need to be sized conservatively or they will overflow in heavy rain events. A dry well is not a good candidate for a large area of saturated lawn — it is more suited to a point-source problem like a single downspout.
Where there is genuinely no gravity outlet and the water table is causing problems, a sump pit and pump can move water mechanically to a street or ditch. This is an appropriate last resort, not a first choice. It introduces a mechanical component that requires power and can fail, and it carries ongoing maintenance. Before recommending a pump, a good contractor should exhaust the gravity options first.
A catch basin is a surface inlet — a grated box set into the ground at a low spot — that connects to an underground pipe and routes the water to an outlet. It handles surface runoff better than a French drain does, because it intercepts the water before it soaks in. Channel drains (linear slot drains) do the same job across a paved area or driveway. These work well when the water problem is runoff pooling at a specific point, not groundwater rising from below. They still need a workable outlet.
A significant share of residential wet-yard problems in Washington County trace back to downspouts that discharge against the foundation or dump into a poorly located underground connection. Extending a downspout with a surface diverter or a buried solid pipe to the street or a side yard can eliminate a problem that looked like a French drain job. It is worth checking where every downspout discharges before digging anything. A site evaluation that looks at the full picture — surface grade, outlet options, and all water sources — is the right starting point before selecting a solution.
The starting point is observation, not equipment selection. During or just after a significant rain event, watch the yard for 30 minutes. Note where the water comes from — is it sheeting off a roof, running from a neighbor's property, or rising from the ground itself? Note where it goes — does it drain away, or does it sit for days?
If the water arrives in a defined path from a higher point and you can see where it wants to go but cannot get there, regrading the surface path may be enough. If the water arrives and there is no path — it just accumulates — you need to find an outlet before any underground pipe will help.
If the ground is saturated across a large area and the water table appears to be high, you may be dealing with a regional groundwater condition that no single-property solution fully addresses. In that case, the honest answer may be that you can make the yard more functional but cannot make it dry during a wet January.
A contractor who walks your property, asks where the outlet is, and discusses these options is worth listening to. One who immediately proposes pipe without discussing the outlet question may be selling rather than solving.
Do not install a French drain when there is no workable outlet lower than the problem area. A pipe with no place to discharge water just relocates the puddle. Also avoid French drains when the real issue is surface grading — a yard that sheds water toward a low point because the ground is shaped incorrectly is a grading problem, and regrading is usually faster and cheaper than installing underground pipe.
French drains require an outlet lower than the collection area, which is not always available on flat valley-floor lots. They can silt up over years, especially in heavy clay soil where fine particles migrate into the gravel and pipe. They require digging, backfill, and restoration work. And they do nothing to improve surface grading — if the yard's slope is wrong, a pipe underground will not fix water pooling on the surface.
It depends on what the problem actually is. Regrading the surface is often the better answer when water pools because of slope problems, not groundwater. Downspout redirection is better when the water source is roof runoff hitting the foundation. A catch basin is better when surface water concentrates at a specific point. The right tool depends on where the water comes from and where it can go — there is no universally superior option.
Yes. Gravel surrounds the perforated pipe to allow water to enter quickly while filtering out fine soil particles that would clog the pipe over time. A standard installation uses washed angular drain rock, not rounded pea gravel, and typically wraps the rock in filter fabric to slow silt migration. Skipping the gravel defeats the purpose — the pipe needs a permeable medium around it to collect water along its length.
Often yes, especially when the wet area is near a foundation where the soil has settled and reversed slope. If the surface sheds water away from structures toward a low point at the property edge or street, and the soil is not permanently saturated from high groundwater, regrading can eliminate the problem without any underground pipe. It is worth having someone evaluate the grade before assuming pipe is necessary.
A properly installed French drain with filter fabric and good drainage rock lasts 15 to 25 years in most conditions. In heavy clay soil like Tualatin Valley silty clay, silt migration can reduce that lifespan if the filter fabric is omitted or poorly installed. The pipe itself is durable; the failure mode is almost always the gravel and fabric becoming clogged with fines over time, reducing the drain's capacity.
Most of these questions have a general answer and a site-specific answer, and the site-specific one is the one that decides the cost. If you want a real number for your property, call (458) 272-9359 or send the details and we will walk the ground with you.