Honor Award
International Student Center Rain-Garden
Aarthi Padmanabhan, Student ASLA, and Jeremy Merrill, Student ASLA
Kansas State University, Manhattan, KS
faculty advisors: Lee R. Skabelund, ASLA, and Dennis Day, FASLA

Project Statement

The International Student Center Rain-Garden educates students, faculty, staff, administrators, and campus visitors about low-impact stormwater management solutions by revealing how designed landscapes can elegantly capture and use rooftop and surface water runoff. This rain-garden strategically addresses a significant hurdle to integrating natural stormwater management systems within the urban fabric- namely, the lack of public knowledge of and appreciation for the function and design of these systems- by integrating art, architecture, ecology, hydrology, and people. 

Project Narrative

Project Goals and Objectives
Primary Goals of the International Student Center (ISC) Rain-Garden:

1. Engage students and faculty in a collaborative design-build and service-learning project.
2. Help restore the natural hydrological cycle along the Campus Creek riparian corridor.
3. Educate students, faculty, staff, administrators, and campus visitors about low-impact stormwater management solutions by designing and constructing a rain-garden that elegantly captures and uses rooftop and surface water runoff.

Specific Educational Goals:

1. Help each participant deepen their collective knowledge of both natural and human systems- and how these understandings can be specifically applied to urban stormwater management.
2. Necessitate collaborative, interdisciplinary, cost-effective, and beautiful project work.
3. Require critical thinking about the relationship between design, implementation, and management.

Analysis, Options Considered, and Interested Parties Involved
During Fall 2006, the Campus Creek Stormwater Management Planning/Design Charrette and related university coursework involved over 125 students, faculty, staff, and professionals in the task of considering ecologically-sound ways to treat stormwater on campus. In the process, the following results were achieved:

1. Many ideas for rain-gardens, bio-retention cells, streambank improvements, and other stormwater best management practices (BMPs) were generated during a one-day interdisciplinary charrette. Watershed analyses, water quality monitoring, and contextual site assessment work were undertaken through a "Natural Systems & Site Analysis" course and served as important references for subsequent rain-garden design explorations. Analyses and design ideas generated during Fall 2006 continue to inspire facilities personnel as implementation plans are developed for various parts of the Campus Creek Watershed. As a result, the negative impacts of rapid, pipe-to-stream stormwater runoff are beginning to be addressed on campus, so that Campus Creek streambanks can be stabilized and water quality improved.
2. Local planners, designers, engineers, other professionals, and community leaders were informed about the project and invited to participate. A number of professional designers and engineers attended lectures presented by stormwater management experts and participated in the charrette. During pre-charrette presentations, charrette-related explorations, field tours, and subsequent meetings and open houses many innovative ways to address urban stormwater runoff were demonstrated to campus administrators, to facilities and ISC staff, to university faculty and students, and to visitors to the campus. Local city planning and engineering staff, other professionals, and many local citizens in the region have visited the rain-garden and expressed a keen interest in learning more about the project. Other rain-gardens have been created as a result of this project. 
3. The ISC Rain-Garden (the first rain-garden in the community) has created tremendous interest on campus about the prospect for retrofitting water-and-energy-intensive buildings and landscapes and creating a more sustainable campus environment. Because of the way it speaks to the site and its bio-regional context, this perennial garden has become a touchstone for regional excellence in natural systems based stormwater management.

Design Process
The ISC Rain-Garden was designed to relate to the architecture and the cultural sensitivities of the ISC and was implemented using a $5,000 water quality service-learning grant- with additional support from the state, university, local businesses, suppliers and contractors. The garden is comprised of a variety of plants- some that can withstand wetland conditions and many that can tolerate hot, droughty conditions common in the region. The garden has an intentional, formal structure that embraces a naturalistic planting design. Vegetation in the bottom of the two small basins receives more water than species elsewhere; plants nearest the building receive less sun so that heavy clay soils in this area remain moist for a much longer period of time. Many of the species found within the garden are perennials (flowers and grasses) native to the Flint Hills Eco-region. The garden was designed to catch and slow stormwater runoff pouring off the ISC's Taiwan Wing rooftop as well as nearby areas dominated by turfgrass- thus lessening the amount of water flowing quickly to Campus Creek. Within the first year-and-a-half, the garden was typically able to infiltrate stormwater in less than 24 hours. The garden clearly shows how property owners can reduce runoff volumes while also eliminating or minimizing pollutant and sediment loads to nearby surface waters. The location and design of the garden (including basins and berms, permeable walkways, splash-pads, and a level-spreader) help reduce the impacts commonly associated with stormwater runoff.

Project Implementation
During Spring and Summer 2007, this collaborative design-build project engaged students, faculty, staff, and professionals in the task of implementing a two-cell rain-garden at the International Student Center . Since that time, faculty, staff, and students have been actively maintaining the garden. To date, approximately 90 students, faculty, staff, and professionals have participated in rain-garden construction and ongoing monitoring and management efforts. ISC staff and students participate in maintenance of the garden. 

Implementation included: preparing detailed rain-garden designs; researching and coordinating purchases, donations, and transport of all necessary equipment, tools, and materials; excavating, rototilling and grading the two shallow basins; removing weeds, roots, and sod and transplanting four existing shrubs; placement of nine large limestone slabs to relate the garden to the ISC's eight-foot grid and to serve as stepping stones and pathways through the garden; preparation of the base areas for the two pathways on the north and south sides of the rain-garden; placement and settling/compaction of washed filter stone (gravel) to support the cut pavers along the formal path (on the north side) and the flagstone along the informal flagstone path (to the south); laying cut pavers, heavy edging stones, re-used metal edging, pieces of flagstone, and filler gravel; placing three salvaged limestone pieces (splash-pads) below roof scuppers; repairing storm-damaged areas after heavy rainfall (more than five inches over 36 hours) damaged unfinished areas of the flagstone path and adjacent berm; coordinating the spraying of weeds and plant protection; planting a combination of moist rain-garden, dry fringe (shady to full sun), woodland, ornamental perennials, and woody plants during five different planting days; ordering, hauling and placing five loads of donated mulch; watering plants from rooftop runoff (and by hose as needed); collaborating with sculpture faculty and students to design, fabricate, and install three silicon bronze rain-bowls; collaborating with bio-agricultural engineering faculty and students to do infiltration tests; regularly weeding; soliciting donations; coordinating volunteers; tracking purchases, budgets and project costs; taking photos; and designing and coordinating the fabrication of an interpretive sign (recognition plaque).

Project Monitoring
Visual observations indicate that the rain-garden readily collects and infiltrates rainwater falling on the ISC's Taiwan Wing and the garden's up-slope watershed from storm events less than approximately two inches. Monitoring vegetative health began in June 2007. Four soil density probes and four infiltration tests were completed in April 2008 and provide a sense of soil conditions within and immediately down-slope of the ISC Rain-Garden. Additional infiltration testing will likely be done in the coming years to see just how quickly water infiltrates into the rain-garden. Bulk density tests will also likely be done to see if soil densities decrease over time (which should occur if compaction/foot traffic is minimized and as native grasses and forbs continue to mature). Ongoing monitoring will help communities learn which plants are best suited for the particular site conditions and show how infiltration rates and soil densities change over time, thus providing important information for future rain-garden and bio-retention designs within the Flint Hills Eco-region. The rain-garden is also a vehicle to educate visitors about the importance of ongoing site maintenance and monitoring.

Other Significant Issues
This project is part of a larger vision for creating a more sustainable campus ? with water conservation, stormwater management, and energy efficiency as primary drivers of proposed activities. The International Student Center Rain-Garden achieves this vision by beginning the process of restoring and revealing the natural hydrologic cycle in an aesthetically pleasing manner and connecting the garden and its users to adjacent buildings and landscape. The garden demonstrates to administrators, campus facilities and grounds personnel, faculty and students, and a wide range of visitors how rooftop water can be readily collected and re-used to nourish a perennial garden consisting of plants native to the Flint Hills Eco-region while also responding to unique site and architectural characteristics. Rain-garden installation used salvaged limestone from a local stone company, thus reducing embodied energy during construction. The garden demonstrates creative use of rain-bowls, splash-pads, a level-spreader, and permeable pavers (employing salvaged cut stone and native flagstone) to slow, temporarily hold, and infiltrate stormwater falling on or entering the rain-garden. 

University personnel, initially skeptical about the ability of very heavy clay soils to properly infiltrate water, now recognize the importance of biological approaches to stormwater management on campus. After breaking up the soil and establishing plants, the dense rain-garden soils now readily infiltrate water while vegetation effectively evapotranspires collected stormwater runoff.