Eda U. Gerstacker Grove at the University of Michigan
Landscape Performance Benefits
Environmental
- Reduces peak stormwater runoff rates by up to 100% for a 2-year, 24-hour storm event and up to 34% for a 100-year, 24-hour storm event.
- Improves water quality by removing up to 80% of total suspended solids for a 2-year, 24-hour storm event.
- Sequesters an estimated 1 ton of atmospheric carbon annually in 179 newly-planted trees and approximately 1 ton of atmospheric carbon annually in 39 preserved existing trees. The trees intercept an estimated 27,000 gallons of stormwater annually.
Social
- Accommodates significant foot and bike traffic even outside of the standard school year. An average of over 430 visitors per hour, primarily students, were observed using the space on three weekdays in the summer.
- Creates a safe environment, with 98% of 52 surveyed users reporting that they feel safe or very safe on-site.
- Provides a community and civic/ceremonial space. Of surveyed users, 78% felt it performs well as a civic/ceremonial space and 78% said it performs well at being a neighborhood space for playing, relaxing, and being social.
Economic
- Saves an estimated 12 labor hours, 13.2 gallons of fuel, and 144 lbs of fertilizer each year resulting in a total estimated savings of $410 as compared to turf within the infiltration beds and no-mow grass areas.
At a Glance
Designer
Stoss Landscape Urbanism
Project Type
School/University
Former Land Use
Retrofit
Location
University of Michigan North Campus
Ann Arbor, Michigan 48109
Map itClimate Zone
Humid continental
Size
4 acres
Budget
$6.5 million
Completion Date
2016
Covering four acres at the University of Michigan in Ann Arbor, the Eda U. Gerstacker Grove promotes quality outdoor engagement at the core of the university’s lesser-known North Campus, home to the university’s art, architecture, and engineering schools. The North Campus central plaza was previously an underutilized open lawn with low ecological value and poor pedestrian circulation. With the introduction of additional tree canopy, improved seating, new walkways, and updated lighting, students and visitors have opportunities to engage with nature and one another in what represents a new approach to campus design on the growing North Campus. The jogging paths and dynamic topography provide a sense of mystery as users move through the site, and the site elements both conceal and reveal various features meant to capture and clean stormwater runoff.
Challenge
- Create a civic space that knits the campus community together and encourages collaborative and multidisciplinary learning while providing much-needed recreation opportunities for students on the University of Michigan’s North Campus.
- Prevent localized flooding and manage and treat stormwater on-site.
- Decrease localized temperatures through increased tree canopy cover.
- Provide space to increase the number and types of outdoor events that can be hosted at the North Campus.
- Five bioretention gardens with a combined filter bed area of 10,355 sf slow, treat, and cool stormwater runoff from the site. Some examples of plantings in the cells include maidenhair fern (Adiantum pedatum) and ebony spleenwort (Asplenium platyneuron).
- Site stormwater that does not infiltrate into the gardens flows to an underground detention and infiltration open-bottom chamber system with an outlet control structure. From there, the stormwater flows to a hydrodynamic swirl concentrator chamber under the volleyball court, which treats runoff and removes 80% of total suspended solids.
- The addition of 179 newly-planted trees supplements the 39 existing trees on the site. The trees provide shade, cool the air, and reduce surface temperatures, which helps to offset the heat island impacts of the buildings and paving.
- Native plants like serviceberry (Amelanchier arborea), baldcypress (Taxodium distichum), common bearberry (Arctostaphylos uva-ursi), and Dakota tall fescue (Festuca arundinacea) were selected with attention to the different microclimates on-site.
- LED pole lighting achieves required light levels for safety while reducing light pollution.
- Acrylic light rods with LED lights in the bioretention beds also serve as an art installation. They gently flicker when stormwater enters the gardens to call attention to the environmental processes and stormwater management technology on-site.
- Precast concrete benches and curbs made from recycled glass reduced new material use and lowered paving material costs by 7%-14%. These elements went through a complex digital design and fabrication process, and as a result they are highly unique in form.
- Areas for student recreation include a full-size volleyball court and 4 swings.
- The selection of the materials and plants need to be considered in tandem with the client’s maintenance capacity to not overwhelm the established protocols.
- When selecting plants to fit the design concept, it is important to consider the aesthetic preferences of the users. For example, Gerstacker Grove is surrounded by the School of Engineering. The engineering students and faculty sometimes do not like the look of the “no-mow mounds” and at times these will be mowed to keep the space looking “tidier”.
- Not all paths are used to the same extent; some are very rarely used. This indicates that some paths could be reduced in size or completely removed to reduce the impervious surface area.
Metal benches: Landscape Forms, Inc.
Precast concrete benches: Wausau Tile, Inc.
Area lighting: Olivio Medio LED/Selux
Clay pavers: Endicott Clay Products Co.
Interlocking concrete pavers: Turf Block/RCP Block and Brick, Inc.
Rubber tiles: Rubber Mat 23mm/Grassmats (USA) LLC
Volleyball edging: Beach Volleyball Rubber Border/Sports Edge
No Mow Lawn Seed Mix: Prairie Nursery
Project Team
Client: University of Michigan Department of Architecture, Engineering, and Construction; University of Michigan School of Engineering; University of Michigan Department of Facilities and Operations
Landscape Architect: Stoss Landscape Urbanism
Contractor: J.S. VIG Construction
Consulting Engineers: The Mannik & Smith Group Inc.
Lighting: Illuminart
Precast concrete: Tectura Designs
Role of the Landscape Architect
The landscape architect was responsible for the concept development and winning competition entry, as well as the coordination between the client and consulting firms. Additionally, the landscape architect was responsible for the completion of site analysis, design, construction, and the environmental goals set forth by the client and design team.
