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Rain Without Pain For once I’m excited about the rainy season starting. Last fall in this column I wrote about rain gardens, a promising new approach to handling water runoff in your yard. Well, this fall I’ve finally built my own little rain garden in my own backyard. I know that lots of folks are interested in these, so I thought I’d share my experiences. by Tom Watson We live in Seattle's Central District, walking distance from downtown, and we just have a small backyard. Our basement has had water seeping in, if not pouring in, the past few winters, and we really wanted to get water away from the house. Part of the problem was that water often overflowed the gutters during heavy rains. We also had one downspout pipe from the roof that went directly into the sanitary sewer system, which is an archaic method that's not considered environmentally sound. So, we had the gutters and downspouts worked on, and we decided to divert water from two downspouts into a rain garden, where the water could collect and then seep into the ground.

I built the rain garden over the past few weekends, taking out the sod, digging down 8 or 10 inches, and adding a layer of compost from my backyard compost bin. It's a small rain garden (about 12 by 8 feet) to fit our little yard, and it curves around an old plum tree.

I formed a berm of soil all the way around it, so the garden can hold a fair amount of water in a heavy rain. Our regular handyman guy put in the piping from the downspouts to the garden, using standard black 4-inch flexible, corrugated high-density polyethylene pipes. The last segment of one of the pipes is slotted and actually under the edge of the garden, surrounded by gravel so it won't clog up, and water should seep out from that pipe into the garden. The other pipe just pours into the garden directly.

The beauty of a rain garden is that you put in native plants and grasses, and then in the summer when it's fairly dry it turns into a landscape garden that attracts birds and butterflies. Since it's fall, the nurseries I've checked don't have much of a selection of native plants right now. But I was able to find a Snowberry and a Pacific Ninebark at City People's Nursery in Madison Valley, and I planted those. I'd like to plant much of the rest of it with native grasses, and I expect to be able to find those in the spring, though I may have to ask buyers at nurseries to order them for me.

The bible for rain gardens in western Washington is a handbook from the Washington State University Pierce County Extension (http://www.pierce.wsu.edu/Water_Quality/LID/index.htm). It includes great info and extensive plant lists. You want to use different types of plants depending on whether they are going to be in the middle of the garden (plants that can handle having very wet roots or even being partially submerged), higher up on the side of the berm, or at the top of the berm. For example, my Ninebark can handle wet soil so it's in the lowest part, and I planted the Snowberry halfway up the berm.

Now I'll just have to wait until we get some really heavy rains to see how it works. By the time you read this, I may already know. It's been a fun project, but now my rain garden needs to do its job. If it does collect the water and let it seep into the soil, and then is eventually filled with flowers and native grasses, it will be more than worth my time and effort.

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