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Three of Virginia’s Most Pervasive Drainage Myths

I talk to a lot of people. It’s part of my job. And a topic that comes up all the time is drainage. I’ve seen bad advice given at parties, online, and even by well-intentioned but uninformed contractors. So that being said, here’s my list of three drainage myths that need to stop.


First, a definition: a French drain generally means a trench, lined with a filter fabric to prevent silt from entering, filled with a perforated pipe surrounded by clean gravel. This pipe runs through the yard and terminates somewhere that the water can flow out and away. It’s that last part that seems to escape people, the fact that the water has to have somewhere to go. I’ve talked with folks who have nightmare scenarios with a low spot and nowhere to move that water, and inevitably at least one person has told them “you need a french drain.” No, no they don’t. With nowhere for the water to go, a French drain just moves the water a foot underground, and any additional water goes right back on top of the french drain.


Granted, this is location dependent. Where I grew up in Rhode Island we had sandy soil that wouldn’t hold water long at all, so drywells were great. In fact, that’s where the effluent from my mom’s washing machine goes, to keep it out of the septic tank.

Virginia clay is a different story. To explain why it’s a problem, let’s look at what a drywell is trying to achieve.

We have a large volume of water where we don’t want it, and there’s no way to get it off the property on the surface. The goal with a drywell is to move it all to one spot underground so it can percolate back into the water table. The challenge is sizing a drywell appropriately. The less free-draining your soil is, the bigger the pit needs to be. Otherwise, one rain squall fills the drywell, and if the next storm comes before the water oozes its way down, your original water problem pops right back. Like this guy:


Now sometimes there is no other option that to put that water underground, but in that case we may need a sump pump that discharges the water somewhere else. It’s my last resort, because I’d always rather keep stormwater out of the storm sewer, but there are times when it can’t be helped. If you’re going to pursue a solution like this, just make sure that wherever you’re discharging the water 1) doesn’t break any laws, and 2) doesn’t adversely affect your neighbor(s) because they can sue you and they’ll likely win.


How much water can you drink in a day? Now, point to where the bladder is on this birch tree:



See the problem? A tree will take up as much water as it needs and, using the roots and vascular system, distribute that water where it’s needed. Anything more? Best case scenario, the plant sits in muck for a while. Worst case scenario, the plant’s roots rot and it dies.

We plant water-loving plants in mucky areas because they are what grows there, not because they’ll turn Shrek’s swamp into a verdant meadow.


Are you still confused about how to handle your water issues? We’re experts, you should call us! 703-679-8550. I’d love to learn more about your project and discuss next steps.

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