u2014 ALE: Wayne Rain Garden Pennsylvania Landscape & Nursery Association u2014 ALE: Wayne Rain Garden Terren Landscapes http://www.terrenlandscapes.com 2014 PLNA Awards for Landscape Excellence winner Category: Residential Up to $15,000 Award Level: Gold Project Description: Our company was contracted by the client to provide a creative solution to an ongoing drainage problem. Their property is located within 30 feet of a local stream that collects storm water from the surrounding area. The nearby stream and high water table caused the lawn area at the side of their home to flood and to remain waterlogged for a few days after each storm. The client not only had difficulty growing plants in the existing conditions, but also had a problem with mosquitoes due to standing water. Our goal was to design a self-contained, naturalistic rain garden that slowed storm water runoff, allowed for percolation, and promoted infiltration while permitting excess clean water to enter the nearby stream with diminished force. As designed, the rain garden allows the earth to slowly and more naturally absorb excess storm water while filtering out toxins such as excess nitrogen and phosphorous which are frequently found in the landscape, therefore reducing the contaminants entering the stream. A percolation test was conducted with criteria of absorbing a one-inch rainstorm within four hours without overflow. The one-inch storm calculation included an existing downspout from the home, which would be piped into the rain garden to reduce roof runoff. The first test failed due to a deep layer of high clay-content soil. Excavation continued until a layer of sandy loam was reached, the percolation test was repeated, and a successful test result was achieved. Next, the entire rain garden basin was excavated to the sandy loam layer and the soil amended with compost and sand to create a highly porous planting media. Geotextile fabric was placed to help reduce migration of the surface stone into the soil and allow for minimal maintenance. Gravel, river stone and small boulders were carefully placed to achieve the look of a natural streambed. A palette of mostly native plants with a few non-invasive ornamentals were chosen for their ability to survive in extreme conditions ranging from floods to drought and were placed according to their specific preferences. Wetland plants were chosen for the lowest portion of the rain garden as that area remains saturated for longer periods of time, with a Chionanthus virginicus as a focal point surrounded by irises and ferns at the lowest depth. Plants tolerant of drier conditions were chosen for the upper edges of the garden. The beautiful colors of Monarda, Ligularia, Eupatorium, Solidago, Chelone, and Rudbeckia were scattered within the upper edge, while movement and softness were incorporated by use of the graceful Nassella that lines the border. Finally, winter interest was provided with a backdrop of Cornus sericea. As built, this small rain garden creates tremendous impact by decreasing the amount of storm water runoff not only on our client's property, but also in the neighboring stream. It serves as a means of slowing the water and providing an area for infiltration back into the earth. The plants provide a habitat for birds, butterflies, and insects, working in harmony with nature and providing beautiful visual interest year-round. Photo Credit: Lisa C. Falls