Sweetwater Spectrum Residential Community for Adults with Autism Spectrum Disorders



Sonoma, CA | Roche+Roche Landscape Architecture | Client: Sweetwater Spectrum


Sweetwater Spectrum is an innovative and pioneering model for meeting the unique everyday living needs of adults with Autism. Building on published research and working with the non-profit board of directors, the City of Sonoma, the architect, and other consultants, the landscape architect fashioned an environment that supports the project’s goal of providing residents a ‘life with purpose’.

The 2.8 acre campus in the City of Sonoma includes four residences, each with four bedrooms; a Community Center with teaching kitchen, workout studio, library, and a space for art and music; a therapy swimming pool and two spas; pathways, site furnishings, hammock garden, play lawn and plantings; and a 1.25 acre organic vegetable garden and orchard with greenhouse.

The site location, sustainable landscape, and organic gardens are an integral part of the living, working, learning and social environment for residents, staff and visitors at Sweetwater.



Autism is the fastest growing developmental disability in the United States, affecting 1 in 68 children, according to the CDC. There is no known cure, and most public services end at age 22. In the coming decade, as many as 500,000 American children with autism will reach adulthood, yet very few residential options exist to care for them. More than 80,000 adults with Autism across the country are on waiting lists for residential placements, with waiting periods as long as 8-10 years. Existing programs can create safe environments but generally isolate those with autism, not taking into account the fact that adults with Autism can and should have a range of choices and the ability to lead productive, fulfilling, independent lives with opportunities to socialize and integrate into their communities. Few of the available housing opportunities fully address the behavioral, sensory, and communications challenges of residents.

The Project

In 2009, a group of Northern California families of children with autism collaborated with professionals and civic leaders to found a non-profit organization with a vision: to design and build a residential community for adults with autism unlike anything available today. The group raised money, engaged consultants, and researched existing group homes and residential communities. They found and secured several adjacent undeveloped parcels in a residential neighborhood in the City of Sonoma in northern California, and clarified their mission: to provide adults with autism an innovative, supportive residential community that challenges each individual to reach his or her highest potential. Their founding principles:

The 2.8-acre infill campus includes four residences, each with four private bedrooms and shared kitchen, living room and terraces; a Community Center with teaching kitchen, workout room, library, art and music, and a large plaza; a therapy swimming pool with two spas and restroom; defined pathways, custom site furnishings, and play lawn; semi-private garden spaces; and a 1.25 acre organic vegetable garden and orchard with greenhouse and chicken coop.

Autism-specific Design

The physical environment for persons with autism is very important; they are often sensitive to outside stimuli. Some are uncomfortable with physical touch, or unable to make eye contact. The resident population also spans a broad range of levels of functioning. Some residents enjoy regular employment, study or volunteer in the community. Other residents are non-verbal or barely verbal, and may have motor skills challenges or impulse control issues.

Working with the client, the architect, and the City of Sonoma, the landscape architect built on published research including the excellent ‘Advancing Full Spectrum Housing: Designing for Adults with Autism Syndrome Disorders’, by Steele and Ahrentzen at Arizona State University, and ‘Opening Doors: A Discussion of Residential Options for Adults Living with Autism’, by the Southwest Autism Research & Resource Center. Sweetwater has been designed with special considerations to minimize visual stimulation, ambient sound, lighting and odors. The progression of spaces from private room, to shared house, to the Sweetwater campus, to the greater Sonoma community is carefully designed to allow residents the ability to advance or retreat as needed. Spaces are designed to be simple and predictable, with transitions from one space to another left open to allow previewing of the next space. Water features are absent, and shade structures are either solid or of simple design, to eliminate distracting refraction and shade/light patterns. The plant pallet is mostly ‘quiet’, utilizing subtle and soothing variations of foliage color and form, and avoiding profusions of brightly colored blooms.

The swimming pool and the large plaza with basketball hoop, table tennis, play lawn, and seating allow for group activities and community interaction. Smaller outdoor rooms such as the hammock garden provide opportunities for individual time or one-on-one interaction, as well as the self-soothing effect of repetitive motion. Plant material and low site walls provide separation and definition of spaces without preventing staff monitoring. ‘Proximate seating’, benches on opposite sides of a low wall or at a discrete distance, allows residents to observe or participate at their own comfort level. A non-scalable fence and monitored gates provide privacy, security and containment for residents at the perimeter of the site. The property is essentially level, allowing all public and private spaces to be universally accessible, including the pool and spas and the greenhouse.


The project site, surrounded on all sides by residential neighborhoods, was intentionally chosen for its proximity to bike paths and public transit, within easy walking distance of shopping, banking and employment opportunities.

Wherever possible, construction materials and practices are safe, non-toxic, environmentally sound, and sustainable, utilizing locally sourced materials, and installed by local subcontractors. Lumber for fences and benches is FSC-certified; stains and sealers are low- or no-VOC. To achieve the required goals of durability and cost effectiveness, a family of site furnishings of board-formed concrete and cedar slabs was employed. Concrete with integral color was used for primary paths, with crushed gravel providing a softer counterpoint for secondary spaces. The custom pool fence meets pool safety codes, but utilizes a steel coil fabric that avoids pinch points.

As a part of the sustainable site strategies and to provide for storm water management on site, pervious gravel paving was used for parking areas and drives, and the site is ringed on three sides by bio-swales. Plant material is drip irrigated using water from an on-site well, and was selected to meet the city’s water efficient landscape ordinance while providing year-round interest, shade, and relief from the built environment, and avoiding potentially irritating, sharp or toxic leaves and fruit. The plant palette leans heavily on California native trees, shrubs, perennials and ornamental grasses, supplemented by Mediterranean climate adapted selections. Bio-swales feature riparian plant material that can handle annual winter inundation, but survive the hot dry California summer with minimal irrigation. The organic farm and orchards provide healthy produce and eggs for residents, staff and visitors.

Sustainable features of the architecture include cool roofs, solar PV panels and solar water heating, natural ventilation, day lighting and solar tube skylights, high R-value walls and roofs, high performance windows and radiant floor heating.

Created as a pilot community, Sweetwater Spectrum represents a long overdue model that is intended to be replicated nationwide.

"A high level of design directed to a population that typically gets ill-considered design. Often the most in need of good design receive the least."

- 2015 Awards Jury


Landscape Architects:
David F. Roche, ASLA
Structural Design Group, Structural Engineers
Timmons Design Engineers, Inc., MEP
LeddyMaytumStacy Architects, Architect
Adobe Associates, Inc, Civil Engineers
Midstate Construction, General Contractor
Landesign Construction & Maintenance, Inc, Landscape Contractor



Sonoma Compost, compost and mulch
Soil and Plant Lab, soils testing


Bluestone Pool and Landscape, Swimming Pool Contractor
Kenwood Fence Co., custom fences and benches
Midstate Construction, custom walls and paving
Shamrock Materials, concrete
Scofield, integral color

Architectural Lighting Design, Lighting Design


by others


NDS, drainage products
ACO USA, brickslot drain


Cascade Coil, custom pool fence
Kenwood Fence Co., custom fences and benches
Midstate Construction, custom walls and paving
DKS, gate keypad
Viking, gate operators


Hunter, spray heads
Irritrol, controller
Weathermatic, remote control valves
Netafim, drip tubing


Landesign, custom steel headers
Kenwood Fence Co., FSC cedar for fences and benches


Belson Outdoors, bike rack
Twin Oaks, hammocks
Lifetime, basketball standard
National Pool Tile, pool tile
SR Smith, pool handrails
Competitor, pool lane lines
LifeGuard, pool lift


by others


West Coast Wire, vine cables
Chicago Hardware, turnbuckles