Longer Downspout Extensions

2006.11.11

I’ve started thinking more seriously about some kind of drain tile / drywell system to divert groundwater away from my basement foundation.  I’ve also thought about an additional, separate system to take water directly from the downspouts to a drywell further out in the yard.  My house has three downspouts, two of which are at the back corners.  That means two-thirds of the rain hitting the roof is getting discharged there, which is exactly where I have the flooding problems.  Even the four- to six-foot extensions I put in place this year weren’t enough.

I drew up a plan for the two systems, and then went to Lowes today to price components, mostly perforated PVC pipe and fittings.  The drywells I would be ordering online (or as a cheaper alternative, use a couple 44-gallon Rubbermaid trash bins), and then the crushed gravel for backfill would come from a local landscape supply.  I came back home from Lowes and started putting the numbers together.  What I came up with suggests that this would cost in the $500 - $800 range, and that’s if I did all the digging by hand.  The drywell holes especially would have to be quite large, about five or six feet in diameter, by at least that deep.  Realistically, I’d have to rent a backhoe (or hire someone), so that puts the cost at $1000 or more.

Wow, that’s a lot to spend.  I’ll have to think about this for a while.  It seems like a high price to pay to hopefully (and no guarantees) avoid a minor flooding problem once or twice a winter.  Especially since I only plan to stay in this house another three or four years.  (Although I can’t predict the future, of course, I could be here longer.)  Now if our winter rains fall into this pattern more often, and I’m having to bail out the basement every month… that’s a different story.

2006.11.25

After additional flooding in the basement, I decided to try extending the downspouts further, to see if that would help.  A lot cheaper and easier than digging trenches, so worth a shot.  We had a rare sunny day today before another front moves through, so I decided to take advantage of the break in the rain.  I went to Lowes to pick up the supplies.  I discovered that you can fit a couple 10-foot sections of aluminum downspout in a Honda Civic, provided you don’t mind giving up most of your passenger space and holding the trunk lid down with a bungee cord.

I augmented the single extension with a flexible vinyl elbow (great invention) and one of the 10-foot sections of downspout.  I removed the bottom two elbows from the vertical downspout so I could start the first extension at a higher elevation.

On the other downspout, I had tried this green flexible extension.  It just doesn’t go far enough away from the house, and, because the existing downspout came down so far to the sidewalk, the flexible extension ended up traveling slightly uphill for a couple feet, which is definitely not what you want.  When I pulled it off, it still had water in it, even though the rain tapered off yesterday afternoon.

The first step was to cut off the bottom of the existing downspout with a hacksaw.  I’d forgotten what a grating experience this is… it makes the most excruciating screeching sound that reverberates through the neighborhood.

Then I slipped on an aluminum elbow and affixed it with some screws.  Next a flexible elbow, 10-foot section of downspout, and finally, the green flexible extension at the end.

Well, they look kinda silly, but if they help keep the water out of my basement, it’s worth it.