SUNSHINE PARK. RAIN GARDEN A project by the Partnership for the Umpqua Rivers & the City of Roseburg

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1 SUNSHINE PARK RAIN GARDEN A project by the Partnership for the Umpqua Rivers & the City of Roseburg

2 Table of Contents Introduction..3 Intent of Booklet Bioswales/Rain Gardens Benefits of Rain Gardens Background..4 Roseburg, Oregon Sunshine Park Site Information Site Plans..6 Site Considerations Planting Plan Cross Section and Plan View Process..8 Donations & Collaboration Conclusion...10 Sustainable Stormwater Management Acknowledgements & References Table of Contents

3 The Intent of this Booklet This booklet was created to serve as a resource and example for residents in Roseburg, Oregon. The methods used were specific to the soils and conditions at the Sunshine Park site, but similar conditions may be found throughout the city. Because of this, the project is meant to serve as a pilot for those hoping to learn more about bioswales in Douglas County. As a disclaimer, this booklet is merely an example of one project s implementation. Further research is highly encouraged if one is planning to construct a rain garden. What is a Bioswale/Rain Garden? Rain gardens are depressions in the ground that help offset the effects of impervious surfaces. Rain that historically would have fallen directly on the ground and slowly percolated through the soil is now affected by urban development. This rain instead now falls on parking lots and roofs and is quickly drained off, taking with it any oils and pollutants that may have soaked into the paved surface. The result is that water that previously would have slowly filtered through soil and plants now enters creeks and rivers immediately after rainfalls, potentially carrying these pollutants along with it. All of these impervious surfaces add up, increasing the overall effect on a watershed. Sunshine Park North Pavilion Naturally Occurring Bioswale What is the Benefit of a Rain Garden? These structures can help address some of the aforementioned problems by slowing water, filtering rainfall and reducing pollutants entering our waterways. A rain garden is a small but efficient way to positively affect the watershed. With an integrated and large-scale approach bioswales have the capacity to contribute significantly to the watershed s health. 3 Introduction

4 Roseburg, Oregon The city of Roseburg is located in Douglas County, Oregon and situated on the South Umpqua River. There are a significant number of developments adjacent to the river and its contributing creeks, including industrial, municipal and private. The rain garden project itself is located approximately 100 yards from a tributary of Deer Creek. In its upper reach, Deer Creek runs adjacent to ranching operations and private landowners before winding through the city of Roseburg and converging with the South Umpqua River near downtown. According to the City of Roseburg Parks Master Plan, the population of the city and its surrounding areas totaled 25,490 residents in the year This population is projected to grow significantly in the upcoming decades, making emphasis on sustainable responses to urban growth even more important. The Master Plan also highlights the growing population of older citizens, due to Roseburg s popularity with retirees. (5) Roseburg From Above What is Important to the People? In a region heavily focused on natural resources, populated primarily with families and older residents, and projected to grow steadily, what becomes most important when looking toward the future? When surveyed, Roseburg residents placed environment, parks, and trails in the highest priorities in terms of quality of life in the city (Master Plan 2008). These findings further emphasize the importance of offsetting the effects of urbanization on the watershed, especially within the city s parks. In order to preserve these resources it is necessary to plan proactively and incorporate these types of low impact development into the existing infrastructure of the parks. 4 Background

5 Sunshine Park Site Information Sunshine Park is located approximately five miles east of Roseburg s downtown area. It is the newest among Roseburg city parks, and of its 85 acres 40 are undeveloped natural areas. There is a significant number of users during the week day, primarily walkers and pet owners. During evenings and weekends the park is used more heavily by families for sporting events and outings. This is the very demographic that emphasized the importance of environmental stewardship and upkeep in Roseburg s park systems. The high potential exposure of the rain garden to this demographic will help reinforce the importance of this type of system in developed areas. Restoration on Site 5 Background The small tributary to Deer Creek, located 100 feet from the rain garden site, is the target of a freshwater mitigation plan which was completed in The project aimed to create a canopy along the stream s riparian area, while stabilizing banks and restoring a wetland and wet prairie area. (Land And Water Environmental Services, Inc.) Willow, Oregon Ash, and other native plant species were used in plantings. The rain garden s proximity to this restoration site makes its implementation significant; the swale will make a small but positive contribution toward this effort.

6 Site Considerations The soil at the Sunshine Park Rain Garden site is classified as Curtin Clay, the upper layer composed of black clay. According to USDA s Soil Survey of Douglas County, the soil has poor drainage and slow permeability, with high shrink-swell potential. (122) Given the soil s properties, the bioswale was designed with shallower depth than normally recommended for well-draining soils. The existing slope was also maintained within zone 3, enabling percolation of water to occur not only into the soil, but also along the downslope. In this way the soil s poor drainage is offset by the naturally occurring slope, and the bioswale will not become oversaturated. Planting Plan Plants native to Southwestern Oregon were selected to populate each of the four zones. Among these included: Zone 1: Tufted Hairgrass, Large Camas, Slough Sedge, Common Rush, Slough Sedge, Western Buttercup Zone 2: Largeleaf Avens, Idaho Blue-eyed Grass, Yarrow Zone 3: Pacific Ninebark, Red Osier Dogwood, Indian Plum, Nootka Rose, Elderberry Zone 4/Buffer: Pacific Serviceberry, Red Flowering Currant, Pacific Crabapple 6 Site Plans

7 Site Plans The plan to the right shows the gutter and piping systems installed on the pavilion which drain into the bioswale. The plan below highlights the four different planting zones incorporated into the rain garden s design. 7 Site Plans

8 The Process After the site was chosen based on availability of the city, planning for the project began. It was decided that the rain garden would offset the impervious surface of the adjacent pavilion s rooftop. To determine the ability of the soil to drain this rain water, a soil infiltration test was performed. Given that grade is also an important factor in drainage, the site s gradient was identified. Finally, to calculate the total drainage area measurements of the pavilion s roof were taken. The rain garden s size and depth were then determined based on these measurements Identifying Site Gradient 8 Process Wetland Sod Flats Specific adaptations to the design were made based on the site s nuances. (For more information about this calculation, see the References section of this booklet.) After the four planting zones were determined, native plants were chosen to populate the garden. Flats with native wetland grasses were started to later be placed in the deepest, wettest zone. Soon thereafter one truckload of amended soil was delivered to the site to use during the planting day. Fencing was also purchased for the perimeter of the site, due to the dense population of white tailed deer in the area. The pavilion was later fitted with gutters, downspouts, and piping to direct the water s flow from the rooftop into the rain garden site.

9 Donations & Collaboration The Sunshine Park Rain Garden project was completely volunteer-based in terms of organization and implementation. The Partnership for the Umpqua Rivers was the rain garden project lead and funder. The City of Roseburg was the primary partner in this effort, offering the site itself, gutter and piping installation, a large portion of the plants, amended soil delivery, and local expertise. The nearby Phoenix Charter School donated another portion of the native plants. Local Ameri- Corps members volunteered to install and plant the rain garden itself. 9 Process

10 Conclusion This project is a contribution towards the much larger goal of sustainable stormwater management, and the Sunshine Park Rain Garden is intended to serve as a resource for residents of Douglas County, Oregon who wish to undertake a similar effort. To offset, by any amount, the effects of impervious surface runoff is a positive contribution to the health of the watershed. This aligns with the overall focus of the Roseburg community: preserve natural areas and improve the health of the environment. Roseburg is uniquely situated to implement projects such as these to reach their main goals. The potential for development in this area is high, and integration of these practices early on is key to preserving natural resources. 10 Conclusion

11 Acknowledgements This project was implemented as part of Oregon State University s Master Watershed Stewards course. The project manager s goal was to not only fulfill the course s community service requirement but to contribute positively toward the health of the watershed. Many thanks to all of the people and organizations that helped to make the project happen, including the Partnership for the Umpqua Rivers, the City of Roseburg Public Works, Phoenix Charter School, and all collaborators and volunteers who took time to contribute to the rain garden. Project Manager: Bridget Ayers Looby Partnership for the Umpqua Rivers/AmeriCorps City of Roseburg Partner: Tracy Pope City of Roseburg Project Collaborators: Michael Rooney AmeriCorps Vincent Weeks AmeriCorps Chris Roe Umpqua Watersheds Terry Burleson Partnership for the Umpqua Rivers Volunteers: Janessa Daum AmeriCorps Booklet Design: Bridget Ayers Looby References City of Roseburg Parks Master Plan. MIG Emanuel, Robert, Derek Godwin, & Candace Stoughton. The Oregon Rain Garden Guide. Corvallis: Oregon State University Land and Water Environmental Services, Inc. Freshwater Wetland Compensatory Mitigation Plan Roseburg Pojar, Jim & Andy MacKinnon. Plants of the Pacific Northwest. Lone Pine Publishing United States Department of Agriculture (USDA). Soil Survey of Douglas County Area, Oregon: Part I. 11 Acknowledgement & References Ayers Looby, Bridget. Partnership for the Umpqua Rivers. 2012