PRB Articles


A Rock-Solid Design

Photos Courtesy Of Bill Tiimmerman

Preserving open space, respecting existing neighborhoods, and creating a demonstration project for sustainability were the primary guiding principles in the design of George “Doc” Cavalliere Park, north of Scottsdale, Ariz. The park is the result of more than 20 years of planning and extensive community input in order to meet the significant challenges of integrating a community park into a regional stormwater-retention facility, all set in a sensitive desert environment.

The design utilizes a limited palette of native materials and reductive design principles to create a modern architectural aesthetic, nestled into a dramatic SonoranDesert site. Constructed almost exclusively from native stone, concrete, and unfinished steel, the resulting project has established a new standard for the design and implementation of a truly sustainable public space within an arid site. In recognition of this accomplishment, CavallierePark was selected by the ASLA’s Sustainable SITES Initiative as a Pilot Project, and is the first certified SITES project in Arizona, having received the highest certification level awarded to date.

Stormwater Retention

Located on 34 acres of rugged terrain, the site had been previously developed as part of north Scottsdale’s regional stormwater-management system, including the construction of a large earthen dam and two significant retention basins. Project requirements included the enlargement of the upper basin to accommodate a total of nearly 50 acre-feet of stormwater volume, dramatically influencing the park’s layout and design.

The design of the park elevates the relationship between park and stormwater-management by responding to environmental and user concerns. Extensive community workshops established a project program that included open-turf playfields, lighted sport courts, shaded playgrounds, group gathering areas, hiking trails, restroom facilities, and 42 parking spaces, along with the preservation of most of the site as natural open space. Every effort was made to incorporate all of these requirements in order to minimize site disturbance while at the same time maintaining the park’s functional uses, even during periods of stormwater inundation.

Blending In

An extensive system of more than 4,000 rock-filled gabion retaining walls created a steeper slope on the uphill side of the new basin, thereby greatly reducing the area of native desert disturbance. The gabions blend into and celebrate the inherent beauty of the site’s rugged typography, and, like many park features, derive their aesthetic value from an underlying practical concern. The native rock was artfully hand-placed into custom gabions to form the central restroom facility, retaining structures, seat walls, and stairways. To further celebrate the singular beauty of this native material, the design incorporates a dramatic freestanding “Window Wall” that appears to rise out of the ground north of the main shade pavilion. Openings of various sizes are incorporated into the structure to frame distant views, and to create dynamic patterns of shadow and light across the adjacent turf panel.

All site elements were custom-fabricated from cast-in-place concrete and/or unfinished steel, including a dramatic series of three freestanding “focal walls” that perfectly frame the peak of the site’s granite pinnacle. Natural steel elements include the dramatic central shade pavilion, which mirrors the shape and slope of the adjacent desert landforms, and steel retaining walls built around the large native mesquites, allowing them to be maintained in situ.

The entry drive, parking, restroom, and playgrounds were all sited above the 100-year floodplain, while other elements were set at tiered elevations to further minimize disturbance. A large, open wildflower field/play area was designed as an elevated plinth that can be used even when the retention basin is inundated with water. A second play

area was set on a slope and utilized an artificial-turf system made from 100-percent recycled plastic. In response to neighborhood concerns, the lighted sport courts were terraced into the side of the existing slope to lower the elevation, thereby reducing their visibility to the existing homes.

Native-Plant Palette

Of vital importance was the preservation and restoration of the site’s natural resources. The project utilizes a 100-percent native-plant palette. All native trees, cacti, and plant communities were surveyed as part of the design process. A number of beautiful mesquite trees that were too large to salvage were incorporated into the layout of the parking and shade structure through the use of steel retaining-wall systems that preserved the existing grade around the trees. All other trees and cacti were salvaged and re-used onsite to restore significant areas of desert upland and riparian-plant communities. Parking, driveways, and paths were paved with stabilized, decomposed granite, which used only site-salvaged materials, and dramatically reduced drainage runoff and the urban heat-island effect, while retaining the natural desert character. Designated parking for carpool and low-emission vehicles continues to encourage sustainable user practices, as well as the connections to the citywide trail system that provide access for pedestrians, bicyclists, and equestrians.

The steel, concrete, and rock-filled gabion baskets provide a regionally appropriate and sustainable material palette, and make up most of the materials on site. All elements were custom-designed, using either steel (waste receptacles, parking stops, signage) or concrete (benches, tables, countertops). The naturally rusted roof panels, structural components, steel planters, the bridge, and other site elements are all made from high-percentage content, recycled steel, and continue the palette of desert colors and textures found in the paving and gabion structures. The strict use of natural, unfinished materials has eliminated the onsite release of VOC’s, and will greatly reduce future maintenance costs. Even the lines of the basketball courts are natural, since they are sandblasted in place instead of being painted.

Structural Components

The shape and design of the central canopy and restrooms took their form directly from the nature of the site, with the roof closely mirroring the slope and tilt of the adjacent mountainside, and the restroom walls having the same gabion construction as the site retaining walls. In addition to providing shade, the canopy roof also functions as a large rainwater collection area, which directs water into a central basin, where it is then distributed to the native landscape.

Utmost attention was paid to reducing energy usage and costs. High-efficiency LED lighting was used throughout the site, with all lights continually monitored through a central Greengate Controlkeeper system. A grid-tied 24-kilowatt solar photovoltaic system provides 100 percent of the park’s energy requirements, resulting in a net-zero energy-consumption site.

Recognition For Excellence

It is fitting that George “Doc” CavallierePark has been named after one of Scottsdale’s founding fathers. The new park sits adjacent to “Doc’s” beloved Greasewood Flat, and the design’s commitment to honoring the site’s natural-desert resources, while also creating a sustainable modern aesthetic, successfully bridges the history of north Scottsdale with its future. In recognition of this accomplishment, the park was chosen as the site for north Scottsdale’s celebration of Arizona’s Centenary in 2012.

The park has also received national recognition for sustainability and design excellence from such organizations as the ASLA, ASCE, AIA, SITES, Architizer A+ Awards, Tucker Design Awards, and Arizona Forward.

Chris Brown , FASLA, is a partner at Floor Associates, a landscape-architecture firm based in Phoenix, Ariz. Reach him at (602) 321-2818, or chris@floorassociates.com .

------------------Sidebar-------------------------------

The Team Players

George “Doc” CavallierePark

Scottsdale, Ariz.

Design Team:

Lead Design/Landscape Architect:  Christopher Brown, FASLA, Floor Associates

Architect:  Phil Weddle, FAIA, Weddle Gilmore

Civil:  Leslie Kland, CE, Kland Engineering

Structural:  Greg Bakkum, Bakkum Noelke Engineerers

Electrical:  Doug Woodward, PE, Woodward Engineering

Contractor:  Markham Contracting

Paradigm LED Wins GOOD DESIGN Award

The Art Of Recognizing Others

0