If we haven’t met before allow us to introduce ourselves. We are Back 40 Landscaping and our expertise is in retaining walls, hardscaping and drainage. We also like to bring education to those looking for retaining wall and drainage solutions.
A basic drainage system has 3 components
Additional systems are available to drain lower grade areas, collect surface runoff from driveway and patios, handle water behind retaining walls, and drain any other place you can think of.
Even if it appears you have all 3 components, parts of it could be poorly designed, or installed. It’s very common for areas of a yard to be flat which prolongs the drying time after a heavy rainfall. In the past it was normal for an operator to grade by eye, but time after time operators got it wrong. With the advancements of lasers, sites are now laser graded to a perfect preset slope. Proper grades move water away from higher areas by using gravity; A scientific principle that doesn’t fail.
Unfortunately, it’s all too common that perimeter drains and downspouts are tied into together. From the surface you would never know this, as they both use the same white pvc pipe. This allows all of the collected water from your roof to escape underground at the base of the foundation. Eventually the perimeter drain will collect this, but not before the water has made your foundation footer wet, and potentially entered your basement or crawl space.
All of the pipes around your building as well as any other drainage systems (French drains, retaining wall drains, driveway drains) should tie into what’s called a sump. This is usually a large 3-4’ diameter concrete container that sits flush in the ground. There are inlet pipes, and outlet pipes connected to the sump. The outlet pipes carry the water to its designated discharge area (storm drain, ditch, leach field, rock pit, pond, etc.).
The sump is a great connection point as well as a great debris filter. As rain falls on your roof asphalt shingles lose their granules. This makes its way to your gutters, and down the downspouts into your system. Without a sump collection area, this debris clogs pipes deep underground. Instead of having to clean or unearth pipes, the debris ends up in the sump, where it can easily be shoveled out as needed.
Regrading a site after finished landscaping has been installed is a big undertaking.
It’s not always the entire area, but whichever area needs to be regraded will be like starting over.
The process for this in a residential setting involves stripping, trucking and disposal of the grass, excavating the soil to raise and lower areas as to form a downward slope away from all structures.
Another method that does a much better job, and lowers disposal costs of the grass is to use a Harley rake. A Harley rake is a tractor attachment that is similar to a rototiller.
It chews up the grass and top 3” of the soil. It grades the soil, sorts rocks and debris all in one pass.
It’s almost automatic, eliminating operator error.
Adding a perimeter and downspout drain system requires excavating down to the bottom of your foundation, this is often in the range of 2-8 feet deep and 3-4 feet wide.
Unearthing this area requires the use of an excavator and requires digging all the way around your building.
Large piles of soil the size of cars are placed away from the open area so workers in the trench are protected.
Temporarily placing this soil away from your home creates a wide working area that will affect grass, and any plants in the area.
Special care can be taken in certain areas such as around decorative concrete, trees, and valuable areas.
However, it’s important to note this is a major undertaking and extensive landscaping will need to take place afterwards.
This is a very common issue that we see because of how much rain the Fraser Valley gets annually.
It’s an uncorrected problem in a lot of cases because of two reasons.
The first is that in most cases it is not required to be addressed when building a new home, and the second being its wrongfully accepted as something you just have to live with.
French drains are a fantastic way of bolstering your homes defense against water. They are a great add on solution IF built correctly.
A French drain is a U-shaped collection area. It is made by excavating the soil and lining the area with filter fabric, placing a drain pipe in the bottom and filling the trench back in with round rock. The top few inches can be filled with soil so lawn or landscaping can be grown on top.
The problems we see most often is these drains are:
A properly built French drain will move a lot of water, and cost $5000 - $35,000 for a typical residential yard.
Typical process:
Completely hidden from above a French drain maybe a perfect solution for you.
A complete drainage solution includes proper planning, excavation, building, grading, and finished landscaping. It is very difficult, and in some cases impossible to clean up a full project in winter.
Therefore, in order to have the best experience and limited interruption to your life we recommend bolstering your drainage systems between spring and fall.
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