Water sits in a yard for two reasons at once. It has no route out, and the ground underneath will not take it. Fix one and not the other and the puddle moves a few feet.
Before anything gets dug, it is worth knowing which of three separate problems you actually have, because they have different fixes and people spend money on the wrong one all the time.
Three different water problems
Water against the foundation is a perimeter drain job. That is groundwater in the soil beside the footing, and we covered how those systems fail in five signs your perimeter drains are failing.
Water on the driveway or patio is runoff. Hard surfaces shed everything that lands on them, fast, and it has to be caught and carried. That is why driveways flood every fall.
Water sitting on the lawn is this one. Soft ground that should be absorbing rain and is not.
Why the ground stops taking water
Most of the Lower Mainland sits on clay. Clay drains slowly at the best of times, and once it is saturated it stops accepting water altogether. From roughly October through February it spends most of its time saturated.
On top of that, the soil in a typical yard has been driven over. Machines during the build, deliveries, vehicles parked on the grass. Compacted ground has had the air squeezed out of it, and the air is the part that holds water. A lawn can look fine and be effectively a hard surface.
The other common one is a thin layer of decent topsoil over the builder’s fill. Rain soaks through the good few inches, hits the hardpan underneath, and stops. The water is not sitting on the surface because the surface is low. It is sitting there because it has nowhere to go down.
The three tools, and when each is right
Regrading. Reshaping the ground so water runs somewhere on its own. This is the least glamorous answer, the cheapest, and very often the correct one. If a low spot in the middle of a lawn holds water, no pipe will fix the fact that the yard drains toward the middle.
A swale. A shallow, gently shaped channel that moves water across the surface to wherever it is going. Planted with grass it reads as part of the lawn rather than a ditch. Swales handle large volumes cheaply, they are easy to maintain, and they do not silt up and die the way a buried pipe can. Where there is room for one, a swale usually outlives a french drain.
A french drain. A trench of clear crushed rock with a perforated pipe in the bottom, wrapped in filter fabric so the surrounding soil cannot wash into the stone and choke it. It collects water below the surface and carries it off. Good for intercepting water moving downhill toward the house, drying out a chronically wet strip, or handling a spot where a surface channel is not practical.
Here is the part worth being clear about, because it is where most of the disappointment comes from: a french drain is not a soak-away. It does not make water disappear. It is a pipe, and a pipe has to discharge somewhere. Put one in a flat yard with nowhere lower to send it, and you have built an expensive underground puddle that fills up and stays full.
That is also why the filter fabric and the clean rock matter. A drain built with dirty backfill and no fabric silts up, and the day it does, it stops draining. From the surface it looks identical to the day it was installed.
The part nobody explains: where the water is allowed to go
This is the question that decides the whole design, and it almost never comes up until the trench is open.
A yard drain has to discharge somewhere legitimate. In practice that means daylighting to a lower point on your own property, tying into the municipal storm system if the City permits the connection, or being managed on site. What it does not mean is any of the following.
Not into the sanitary sewer. Storm and sanitary are two separate systems. Storm carries rain, roof downspouts and foundation drains to waterways. Sanitary carries what goes down the sinks and toilets to a treatment plant. They are not interchangeable, and cross-connecting them is a real local problem rather than a theoretical one. The City of Coquitlam states that the majority of excess stormwater in the Stoney Creek Sanitary Trunk Sewer arrives through downspouts on private property that were connected to the sanitary system instead of the storm system, and that it has worked to find and correct unauthorized connections. Coquitlam also points out that the portion of the sewer system on your property is yours to inspect, repair and replace.
If your house is older, or if a previous owner did some drainage work themselves, it is genuinely worth finding out where your downspouts actually go before adding anything else to the same pipe.
Not onto the neighbour. Sending your water next door is how a drainage job turns into a dispute. Where the property falls that way, the water has to be caught and routed, not simply pushed across the line.
Not into a creek or ditch without checking. Coquitlam has a Stream and Drainage System Protection Bylaw, and every municipality here has something equivalent. Where a discharge point is going to a watercourse, that is a conversation with the City before the work, not after.
The short version: the discharge point is not a free choice, and it is worth settling at quoting time. A contractor who has not asked where the water is going has not finished designing the job.
What we would look at
Walk the yard during a real downpour, not a drizzle, and watch where the water actually travels and where it stops. That tells you more in ten minutes than any dry inspection. Photograph the puddle while it is there, because two dry weeks erase everyone’s memory of how big it was.
Then it is a question of whether the ground can be reshaped, whether there is a lower point to work with, and where a discharge is permitted. Often the answer is a combination: regrade the worst of it, carry the rest in a swale or a drain, and fix whatever is quietly making it worse.
We handle drainage across the Lower Mainland and the Fraser Valley, and because we do the excavation ourselves the grading and the pipework get designed together rather than one being blamed on the other. You can see recent work here.
Send a photo of where it sits, taken while it is wet if you can manage it, and we will come look. The quote is free.