Drainage Solutions in Kelowna & the Okanagan Valley

People are sometimes surprised to hear that drainage is a real issue in a place as dry as the Okanagan. We get a fraction of the rain the coast does, and half the summer the valley is under water restrictions. So where does the water problem come from? It comes all at once. A hard summer cloudburst dumps an inch of rain on ground that’s baked hard and can’t absorb it. The spring freshet and snowmelt come pouring off the hillsides. Irrigation water runs where it shouldn’t on an orchard slope. And our soils make all of it unpredictable — gravel that swallows water in one spot, silt that sheds it like pavement in the next.

At GroundStone Excavating we design and install drainage across the Central and North Okanagan, and the trick here isn’t fighting constant rain — it’s managing water that arrives suddenly and behaves differently on every soil type. Here’s what property owners ask us about most.

Why do I get pooling or runoff when it barely rains here?

Because dry ground is bad at absorbing a sudden downpour. When silt or clay-rich soil bakes hard over a hot Okanagan summer, the first heavy rain mostly runs off the surface instead of soaking in — so you get sheeting water, pooling in low spots, and erosion on bare slopes from a storm that didn’t even last an hour. On the flip side, the coarse sandy and gravelly benches drink water so fast that it can travel underground and surface somewhere lower down where you don’t want it. Both are drainage problems; they just need opposite solutions, which is why reading the soil comes first.

What’s the deal with water sitting on top of the ground over gravel?

It sounds backwards, but it’s common here. A lot of Okanagan ground is layered — free-draining sand and gravel with a band of dense silt or glacial till running through it. Water sinks happily until it hits that tight layer, then it stops and spreads out sideways as a “perched” water table, sometimes popping out partway down a slope as a wet seep long after the rain stopped. Hillside lots around Kelowna and Lake Country see this a lot. The fix isn’t a deeper hole — it’s intercepting that water with a properly placed subdrain before it reaches your foundation or undermines your slope.

How do you stop erosion on our dry, loose slopes?

This is a big one in the Okanagan, because our silt and sandy soils erode fast once the vegetation is gone and the water gets moving. The pale silt bluffs around Vernon and the lakeshore are the dramatic example — those fine glaciolacustrine silts lose strength and slough badly when they get saturated. We manage erosion with surface shaping that slows and spreads water instead of letting it channel, swales and berms that carry runoff to a safe outlet, rock and vegetation to armour the vulnerable spots, and proper sediment controls during construction. Keeping a slope stable starts the moment it’s cleared, which is why erosion control runs right alongside land clearing and site preparation. The goal is to keep your soil on your slope instead of watching it wash down into the ditch.

What kinds of drainage do you actually install?

We match the system to the problem, but the toolkit usually includes:

• Surface grading and swales to move runoff away from buildings and across the site safely.
• French drains and subdrains to intercept perched water and hillside seepage before it causes trouble.
• Perimeter (foundation) drains to keep water away from basements and crawlspaces — closely tied to foundation excavation on a new build.
• Catch basins and piped systems tied into an approved storm outlet where one is available, which usually means running a utility trench to the connection point.
• Erosion and sediment control on slopes, especially on erodible silt and disturbed ground.

Can drainage and irrigation be managed together?

On orchard and vineyard properties they really have to be. Irrigation puts a lot of water onto sloping ground all summer, and if it isn’t controlled it runs off, erodes rows, and pools at the bottom of the block. Meanwhile the same property has to handle storm runoff and snowmelt the rest of the year. We look at how water moves across the whole parcel — where it lands, where it concentrates, where it needs to go — so the drainage works with your irrigation rather than against it. In a region where every drop of water is regulated and precious, sending it somewhere useful beats sending it down the road.

Do I need a permit, and where does the water go?

Connecting to a municipal storm system and larger drainage works can require permits and approvals, and the rules vary by community across the valley. Soil and grading work can also fall under local bylaws like the City of Kelowna’s Soil Removal and Deposit Bylaw No. 9612, which can trigger an erosion and sediment control plan on bigger jobs. Where your water ultimately goes — an approved storm connection, a ditch, a swale, an infiltration area — depends on your location and the approvals available. We figure out a legitimate outlet as part of the design, because a drainage system that just dumps the problem onto a neighbour isn’t a solution.

Why GroundStone Excavating?

Okanagan water problems are sneaky — they show up in flash storms, spring melt and irrigation runoff rather than steady rain, and they behave completely differently on gravel than on silt. We read your soil and your slope, design drainage that handles the way water actually moves on your property, and protect your land from the erosion our dry soils are so prone to. Whether it’s a soggy yard, a seeping hillside or an eroding vineyard slope, we’ll get the water under control.

Water showing up where it shouldn’t? Let’s get it under control.

Book a free, no-pressure on-site estimate for residential, agricultural or commercial drainage in Kelowna, West Kelowna, Penticton, Lake Country, Vernon and across the Okanagan, or explore the rest of what we do to see how drainage fits into the bigger picture.