Dealing with water where it leaves the property
In Virginia, I’ve seen a few different scenarios for how water exits a property. In a lot of subdivisions, everyone’s backyard pitches into a swale that carries stormwater into a storm drain. Even if the swale is on your property, you’re usually prohibited from altering the grading such that it impedes the flow of water into the storm drain. I’ve had well-meaning clients who wanted to channel everyone else’s runoff onto their lots and create a giant rain garden. On a larger property you might be able to pull this off, but in a typical subdivision lot you may cause a lot of problems for yourself and your neighbors.
In my situation, I live in downtown Culpeper. A portion of my stormwater runoff ends up in the street and flows into the storm sewer. As this water rushes down the street it picks up oil residues and other contaminants, which will strain the wastewater treatment plant. For this reason, our best course of action is to try and catch as much water as we can reasonably use, and slow the flow of the remainder so that it can more easily percolate back into the ground.
I’ve even dealt with an unfortunate situation where all the water from two neighborhoods ended up in my clients’ backyard- they just happened to be the low point in the area. In that situation, there wasn’t a lot we could do except to make certain the land was graded away from the house, and try to reclaim enough of the backyard to make it usable. As tempting as it may be, solving your water woes by pushing the water into your neighbors’ yards is not an option! Be very careful any time you change the grading and drainage patterns of your lot. If you create water problems for someone downstream, it will be your responsibility to fix them.
The important point here is that for decades, we’ve treated stormwater as more of a liability than an asset. Having made it through a particularly tough drought two years ago, I think we have a better appreciation of the importance- and occasional scarcity- of water. Paying attention to how water enters and exits our properties can help us make the best use of it and ensure there’s enough to go around.