Rainwater As Art

I just got back from an amazing rain gardens training. When editing my "Stormwater Best Management Practices for Coos Watershed Residents: Every-day Things You Can Do to Keep Coos Bay Clean" (which will be unveiled tonight at the first Lower Isthmus Slough Coffee Klatch meeting) today I noticed I already had a better grasp on how to communicate about some of these ideas. I could really see myself being passionate about stormwater remediation techniques for the rest of my life.

The training was taught by several Oregon State University extension officers in conjunction with Sea Grant and the Oregon Environmental Council. First we learned the definition of a rain garden (a sunken garden bed, or landscape depression, that collects and treats stormwater runoff from rooftops, driveways, sidewalks, parking lots, and streets), and how they function. Then we went outside and did actual site assessment activities for possible rain garden sites on the Lane Community College campus. We tested the percolation rate of the soil (0.5 - 2"/hr is ideal) and noted clay layers (a no-no), measured slope of the site (stay away from slopes 10 degrees or steeper), calculated roof area (rule of thumb: your rain garden should be 10% of the area of impervious surface it will be draining), analyzed what parts of the roof drained to which downspouts, and talked about other constraints on rain garden siting.

After lunch, we broke into groups and started designing rain gardens for different possible sites around the building we had evaluated. We had to adhere to pullbacks (i.e. 10 feet from foundations, 5 feet from sidewalks, etc.), consider sun aspect, aesthetic appeal, conveyance of the water from the downspout to the rain garden, where the outflow will be, what plants to plant where, and so much more.

I have identified a site around the Oregon Institute of Marine Biology's parking lot as a possible rain garden site. It is already a vegetated swale (a grassy depression with no curbs that allows runoff to naturally infiltrate) but it could be a beautiful and education rain garden if we just went in and added selected plants: water-loving plants in the bottom, mesic plants on the slopes, etc. Other highlights include (1) it is privately owned, therefore fewer people I would have to talk to, fewer permits, etc. (2) it would be a great spot to also have an interpretive sign about rain gardens because it is a highly visible, high-traffic spot, and (3) they have already indicated a desire to be eco-friendly by designing a vegetated swale to begin with, I just need to help them take that extra step to make it a rain garden. Stay posted on this idea!