Perimeter drains are the quiet heroes of a dry basement in Coquitlam. They work out of sight, hugging the foundation and ushering groundwater away before it sneaks through a crack. When they fail, you often meet them for the first time in the worst way: a musty smell after a week of rain, a tide line along a foundation wall, or a sump pump that won’t quit. The big question that follows is simple, but expensive: can cleaning save the day, or is replacement the only honest fix?
I’ve crawled more than a few damp crawlspaces around Maillardville and Burke Mountain, and the answer depends on age, pipe material, grading, and the kind Check out this site of debris you’re dealing with. Here’s how to think about it with Coquitlam’s soil and weather in mind.
The local context: rain, slopes, and soil that moves
Coquitlam gets roughly 1,600 to 2,000 mm of rain per year, much of it stacked between October and March. Many lots slope, and newer neighborhoods often include terraced landscaping and retaining walls that redirect surface runoff in quirky ways. Clay and silt pockets aren’t rare, especially in older areas, and they hold water longer than sandy soils. Put those together and perimeter drains carry a heavier load here than they do in drier regions.
The system typically includes a perforated pipe at the footing, filter material around it, cleanouts at the corners, and either a sump or a gravity tie-in to storm. When it’s all working, you don’t notice it. When it isn’t, you learn new vocabulary like fines, biofilm, and root intrusion.
What cleaning can fix, and what it can’t
Perimeter drain cleaning is not one technique, it is a set of tools and methods chosen based on what’s inside the line. Jetting heads flush silt and sludge, chain flails knock off mineral scale and some root hairs, camera heads map the problem, and enzyme or oxidizing treatments can help with organic buildup. In many cases, cleaning restores flow with no digging at all.
Cleaning shines when:
- The pipe is intact but dirty. Silt infiltration after a landscaping project, a few seasons of leaf debris washing into open cleanouts, or algae and iron bacteria buildup will choke a line without damaging it. Jetting at 2,000 to 3,000 psi with the right nozzle angle can scour the interior and push the mess to a catch basin or sump. Roots have found small seams. Hair roots slip in where pipe sections meet, especially at unglued PVC joints or in older clay tile. A combination of cutting and jetting clears them, then you plan root management at the surface. The filter fabric did its job for years, then started passing fines. You’ll often see pudding-like sludge at the low points. Controlled flushing can restore capacity.
Cleaning falls short when the pipe itself is the problem. I still see original clay tile on pre-1975 houses that has shifted on settling soils. Gaps open between bells, and soil slumps in. No amount of jetting fixes a missing segment or a collapsed run. Asbestos cement (transite) lines, common into the 1970s, become brittle and delaminate with age. Even PVC can belly if backfill subsided, leaving a permanent water pocket that collects silt all over again.
If the camera shows deformation, an oval pipe, wide-open joints, or a section that never drains, it’s time to talk replacement or at least sectional repair.
Diagnosing the situation without tearing up the yard
Homeowners sometimes call after being told they need a full replacement based on a single clogged corner. That can be true, but I always ask for three pieces of evidence.
First, a map. A camera with a sonde lets us trace the route and depth. In Coquitlam, drains often jog around porches and stairwells. Knowing the depth also matters because digging six feet down along a concrete walkway is a very different job than replacing a shallow run beside a garden bed.
Second, video. A clear recording during a wet spell tells a lot. Is water entering the pipe from the perforations? Do we see fines swirling? Are roots isolated to one seam or marching for meters? A minute of footage can save thousands by avoiding guesswork.
Third, a drainage context check. Look at downspouts, surface grading, driveways that pitch toward the house, and any recent work like patio installs. I’ve cleared “failed” perimeter drains that were actually overwhelmed by roof leaders dumping straight into the system during a storm. Once we decoupled the downspouts and added a rock splash pad, the drain went back to normal duty.
How age and material guide the decision
Pipe material and the era of construction set expectations.
Homes from the 1950s to early 1970s often used clay or transite. Clay separates at joints and invites roots; transite gets brittle and can flake internally. If these systems still flow, they can often be maintained with periodic cleaning, but they are living on borrowed time. Replacement brings peace of mind and better performance. I’ve seen clay tile look fine in August then admit inches of silt after a January soaker because a joint finally opened.
From the late 1970s onward, PVC became the norm. Properly installed, PVC holds up well. Failures usually trace to installation shortcuts: insufficient bedding, thin cover at driveways, or missing filter fabric. These often respond to targeted fixes. You can dig up and replace a 12-foot failed section where a belly formed, flush the rest, and get years of service.
A quick rule of thumb: if your system is older than 40 years and made of clay or transite, plan for replacement when the first major issue arises. If it’s PVC under 30 years old and the camera shows clean pipe with localized trouble, cleaning and spot repairs are usually sensible.
What cleaning actually involves on a typical Coquitlam home
Picture a 1990s rancher in Ranch Park. Two corner cleanouts, a sump beside the garage, and a tie-in to the municipal storm. After a week of rain, the basement carpet near the back wall is damp. We open the downstream cleanout and find a slow trickle. The upstream cleanout shows standing water.
Here is how we might proceed. We run the camera from the downstream cleanout to map the route and depth, marking any standing water pockets. If we see fine silt and brown slime, we follow with a jetter head designed for heavy debris, starting at a lower pressure to avoid pushing backups into the house. We work in short sections, flushing toward the sump, then vacuum the sump so we’re not leaving muck to recirculate.
If roots show up near a hedge line, we swap to a cutter head, remove the growth, and camera again to check for joint integrity. Once flow is restored, we test during a hose-down and watch the sump. If the water now streams in a steady sheet from the perforations and levels fall quickly, we’ve likely resolved the immediate issue. Finally, we talk about surface water: does the patio slope toward the house, do downspouts discharge near window wells, is the lawn higher than the sill at any point? Addressing these cheap fixes matters as much as what happens underground.
When replacement is the honest answer
Certain findings end the debate. A collapsed section under a driveway, a crushed pipe at a service trench crossing, a long belly holding water year-round, or consistent infiltration of soil through gapped joints all argue for replacement. Another factor is maintenance fatigue. If you’ve needed perimeter drain cleaning two or three times in five years, and the camera shows the same vulnerable joints each time, the cost of repeated service can approach the price of replacement without delivering long-term security.
Replacement today usually means new PVC or HDPE perforated pipe set at proper slope on compacted bedding, wrapped in a clean aggregate envelope with a geotextile that passes water but screens fines. We add accessible cleanouts at every corner and any significant change in direction, and we separate roof leaders from the footing drains unless there is a properly sized storm tie-in with capacity. A well-done replacement reduces risk dramatically and often brings insurance comfort.
Cost realities and how to think about value
Prices shift with access and depth. Cleaning with camera inspection tends to run in the low four figures for a standard single-family home, higher if root cutting is extensive or multiple visits are needed to stage flow during wet periods. Sectional replacement might land in the mid four figures for a small dig, while full replacement around a house can push into five figures, especially with deep footings, concrete flatwork to cut and restore, or tight side yards that require hand digging.
Value is not just the invoice. Consider what you’re protecting. A finished basement with drywall, flooring, and contents might carry $40,000 in quick-loss exposure if water finds a way in. If cleaning provides stable performance for several more years and you can improve grading and downspouts right away, that can be the wise interim step. If the system is at end of life, replacement guards the house and lets you stop worrying every atmospheric river forecast.
How seasons affect timing
In Coquitlam, shoulder seasons are your friend. Camera work and perimeter drain cleaning in late summer or early fall gives you a chance to spot issues before the rains test the system. That said, many calls come mid-storm. Cleaning during wet weather has one advantage: you get to see the system under load. Replacement is easier when soils are drier and less likely to slump, but emergencies don’t schedule themselves. If you must dig in winter, budget for erosion control and restoration of landscaping come spring.
Preventive habits that pay off
You don’t control the rain, but you control what reaches your perimeter drains. Keep roof leaders clear, and if possible, route them to daylight or a dedicated storm line, not directly into your footing drains. Maintain positive slope away from foundation walls for at least the first two meters. Keep cleanout caps intact and tight, especially after yard work. If trees grow near the foundation, choose species with non-aggressive roots, and keep them pruned. A camera and cleaning every five to seven years on older systems is a fair rhythm, more often if you live under big cedars or maples that shed needles and seeds into every opening they find.
A quick decision guide for homeowners
- If the camera shows intact PVC with silt or biofilm, pursue perimeter drain cleaning first and adjust surface water management. If you have clay or transite with recurring root intrusion and visible joint separation, plan replacement, possibly staged in sections. If a specific low spot holds water even after cleaning, correct the belly with targeted excavation rather than hoping it improves. If you’re seeing moisture at one wall only, inspect that segment and nearby grading before assuming the entire system is failing. If service calls are stacking up, compare the total against a well-scoped replacement, including the peace of mind factor.
What to ask your contractor before you decide
Choose someone who arrives with a camera and uses it. Ask to see live footage, not just a summary. Ask about nozzle choices and pressures for cleaning so you know they will protect older pipes. Request a map with depths to understand any replacement scope, and ask how they plan to handle downspouts. Good contractors in Coquitlam also speak the language of municipal storm connections and can tell you what permits are needed if tying into city infrastructure.
One more point from experience: be wary of one-size-fits-all answers. I’ve seen a 1968 clay system humming along because it sat in clean sandy soil with mature landscaping and no big roots nearby. I’ve also seen a 2008 PVC install struggle because the builder sent half the roof into it and skipped filter fabric. The ground tells the truth. The camera confirms it. Your decision should follow that evidence.
Final thoughts from the crawlspace
Perimeter drain cleaning earns its keep when the system still has good bones. It’s fast, less invasive, and often all you need. Replacement belongs on the table when age, material, or deformation has turned the drain into a liability. Coquitlam’s climate rewards proactive owners who check early, manage surface water, and fix what is actually wrong, not what is assumed. If you match the solution to the problem and the property’s stage of life, you can keep your basement dry through the next Pineapple Express and the one after that.