Category Archives: Swales

Digging a Swale

As I had explained in the post Planning to Dig a Swale, we decided to dig a swale to redirect water away from our home. This isn’t the ideal solution for handling the rainwater, but in the short term, it should prevent a pond next to our house during heavy rains and keep water from pouring into our basement. In the future, we’ll find ways to channel this water into the ground.

The first thing we did was to measure and insert stakes into the ground at the proposed corners of the swale. We inserted the first stakes two feet from the lot line (to make lawn mowing easy on that side) and then measured another two feet over for the other stakes. Some twine was laid out between the stakes as a guideline.

After marking the location of the swale, we removed the sod.

After marking the location of the swale, we removed the sod.

Next, we removed the sod from the marked location. The dimensions of the swale are 48 feet long by 2 feet wide, so this produced a large amount of sod. If we had been able to finish this project in a couple days, we could have reused the sod after digging the swale. However, that wasn’t an option, so we piled the sod up in one of the compost bins to make use of later.

Next, we dug the soil out in the swale and adjacent to the pond location. One question was how deep to go in the swale. We wanted it to be deep enough that the water along the house would flow into the swale, but also high enough that the water would still be able to travel away from the house. This proved to be difficult to judge. My husband purchased a laser level, which helped a little, and we tried to use a string to look for irregularities, but the best test was to turn on the hose and see if the water flowed the way we wanted it to. A couple heavy rains helped us to see the effect of the ground’s depth just by looking out the window. The sides of the swale are steeper than they perhaps should be, so we will need to keep an eye out for erosion, but since the ground is such a heavy clay, I don’t expect it will move much. We piled the large amount of dug-up soil next to the house for later regrading.

While digging, we came across a couple of large roots from the Oak tree next to the swale. We didn’t want to chop through the roots and hurt the tree, so instead, we dug tunnels under the roots. The idea is that the water will just flow around roots and keep moving. It seems to be working so far, but we’ll have to keep an eye on that area to make sure that sediment doesn’t build up there and clog the swale. Some of the small roots got chopped, but we tried not to harm them in hopes that they will just get buried again and be fine.

I bought a yard of compost at the Bruce Company and used my Dad's truck to haul it home.

I bought a yard of compost at the Bruce Company and used my Dad’s truck to haul it home.

To prepare for the swale project, we had purchased one yard of shredded compost from the Bruce Company. My Dad helped me haul it home with his truck and it was great fun taking it across the backyard to dump it on a low corner of the yard. That compost would be used for enriching the soil in the swale when we wanted to regrow some grass (it looked unlikely to grow well with only the clay soil). We also thought we could use some of the compost for regrading or filling in some low areas in the yard. We could also use some compost for preparing a strawberry bed or adding to the vegetable garden… compost is just so useful. A yard looks like a lot at the garden center, but when you actually bring it home, it’s not as much as you thought it was. We’ll see how far it goes.

After the swale was in place, we added an inch of compost and then watered it. I handspread grass seed (the package instructed 12 seeds per inch, not 5 or 30) and straw and then lightly watered it again. I set up a sprinkler to make the daily task of watering a little easier.

After the swale was dug, an inch of compost was added along with grass seed and chopped straw.

After the swale was dug, an inch of compost was added along with grass seed and chopped straw.

Our next project will be to regrade along the side of the house. We already can see a great deal of water going through the swale during heavy rains, meaning that we should have less water by the house. But it’s equally important to get rid of the low area right next to the house so the water just doesn’t have a place to build up.


Planning to Dig a Swale

In my post about water in our basement, I mentioned all the rain we received this past winter and spring. Now, almost July, we are still receiving a significant amount of rain. According to Channel 3000, “southern Wisconsin is roughly 10 inches above the average for precipitation [this year], making it one of the wettest years on record so far.”

This past Wednesday morning, I had just published posts related to some initial steps we took to remediate our basement water issue, when what did I find in our basement again? Water.

We had hoped that our basement problems earlier this year were related to the frozen ground and lack of vegetation. Surely, the growing trees and perennials next to the house would drink up the water in the summertime. We had just dug the window wells deeper and removed the landscape timbers to improve drainage. But we had the same problems as before: a deep pond along the south corner of the house and water pouring in below two of our basement windows.

Water gathers on the southwest side of our house during heavy rainfall and then enters our basement.

Water gathers on the southwest side of our house during heavy rainfall and then enters our basement.

We decided to speed up our water in the basement project. I placed a call to Digger’s Hotline with plans to dig a swale this weekend to move some water away from the house.

The south corner of our house is a low area, not only on our property but also compared to our neighbors’ properties. Our house is built lower than our neighbors’ homes so regrading is limited by the height of our siding and the height of the neighbor’s yards. I’m a big fan of wetlands, but when one unexpected forms right next to my house and then invites itself in, it’s difficult for me to click ‘like’ on that. There isn’t room to slide the wetland away from the house. What we do have room for is a narrow swale, catching the water falling from both our property and the surrounding area and channeling it along our lot line away from our house.

Unfortunately, a swale along the lot line means that some of this water will probably end up in the street and sewers. This is sad. Rainwater is a mostly clean source of free water for us all. When it goes to the sewage treatment plant, it wastes energy as it becomes mixed with chemicals. We don’t yet have a rain barrel, but even a rain barrel (at only 50 gallons) would only hold a small percent of the water that pools up by our house. Water containers can be purchased at 250 gallons, but at over $250, they are expensive.

Another problem with water rolling onto the street is flooding. The corner by our house receives a rush of water from the two intersecting streets (and other properties). During heavy rains, the street by our house fills with puddles that reach to the elevated center of the road. Cars zig-zag around the deep water during these flash floods. The sidewalk also becomes one huge puddle. Among our neighborhood, our problem isn’t unique.

Rain gardens would be a good long-term solution for many of us neighbors to implement on our properties. Of course, a rain garden isn’t a quick project. We need to do some research and invest money into plants suitable for rain gardens. For now, we just have a shovel and a little time to dig those swales. But with more education and cheap access to rain garden plants, we could wisely sink the rainwater into the ground.

I was disappointed when I called the City of Madison Water Utility this year and asked about the Terrace Rain Garden Program. The person I talked to seemed to think that this program wasn’t worth the high cost. Perhaps I need to talk to someone else, because I think our property would be a good candidate for this project (if we could only ensure that the water doesn’t overflow into our basement).

In the meantime, we need to get the water away from our basement so that large-scale damage is not caused on our home. Then, once we have a swale, perhaps we could implement rain gardens at multiple points along the swale to absorb the water. To read about the swale we dug, check out Digging a Swale.