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Improving landscape drainage.

Who could have ever imagined Denver having as much precipitation as we have had this year? Not only the amount but the duration of the wet weather has made a tremendous impact on our industry. One of the most common requests this year has been for improving drainage on our client’s properties. As this is not an easy or direct answer for most people, here are some drainage basics.

First and foremost, one of the easiest and most important things you can do on your property to improve your drainage is to make sure that you have adequate slope away from any building structures. This means that you have a minimum of ¼ inch of drop per foot of run. So to grade away from the house 8 feet, you would need at least 2 inches of drop from the house out. The shorter the distance you are able to grade away from the house, the more the slope should be; as much as ½ inch per foot (or more).


Second, once you have addressed the slope around your house and out buildings, you
will want to make sure that you have little to no irrigation within the first three to four feet next to the structure. You should have beds with little or no plantings at the perimeter of the house or a hard surface like a sidewalk or drive. There should never be lawn against any building.


And finally, one of the biggest issues that need to be addressed at most residences is the downspouts. Downspouts should be run well past the drip line of the roof of the house, and should go to a point where the water will not accumulate in a large rain storm. Clogged downspouts, or downspouts that dump at the foundation, are one of the primary reasons people have foundation issues or flooding issues. Downspouts that run into corrugated pipe below grade may seem like a good way to mitigate your water issues, but in reality, over time sediment will build up in the grooves of the pipe and eventually it will clog and back up. This is much more of a problem if the pipe has not been run to daylight (the end is visible) and just run to a “french drain”. Our recommendation: if you need or want to run your downspouts underground, use a solid P.V.C. pipe with a cleanout installed. Cleaning your gutters and checking your drainage on a regular basis will also make a significant difference when we get a heavy downpour.