The University of California at San Diego's Charles David Keeling Apartments contain 500 dormitory beds within three residential buildings, which frame a courtyard and stand adjacent to amenities like basketball courts, a barbecue station and open, natural spaces. The LEED Platinum project manages 100 percent of onsite precipitation over approximately 158,000 square feet with a combination of bioswales, basins, weirs and conveyance channels.

"It never rains in Southern California," songwriters Albert Hammond and Mike Hazelwood wrote in 1972. Water is a scarce resource in the coastal desert landscape and climate of San Diego, but when it does rain, it is both dramatic and fleeting.

Innovative site design at the University of California, San Diego's new Charles David Keeling Apartments for second-year residents established an elegant system to capture this fickle natural resource and increase campus sustainability. Named for famed oceanographer Roger Revelle, who was instrumental in founding the university, Revelle College at UC San Diego already had a propensity for eco-friendly practices.

To unify the Keeling Apartments with the rest of Revelle College, the site features 1960s-inspired local lava rock walls updated with contemporary detail. Plantings include California sycamore, San Diego sedge, deer grass, California gray rush and dwarf coyote bush.

Aptly, the new housing earned its name after rigorous scrutiny by the family of Dr. Charles David Keeling, a Scripps scientist and Revelle College professor, who first alerted the world to the possibility of the human impact on global atmospheric carbon. The new apartment facilities brought displaced students who had to live in other colleges' housing units back to their own campus, creating a space for both learning and living.

The university hired Spurlock Poirier Landscape Architects, along with Kieran Timberlake Architecture, to lead the project. Kieran Timberlake designed the 500-bed student dormitory, and Spurlock Poirier was responsible for site planning and open space programming, from the early stages of the project through construction administration.

Buildings on the north, west and south sides frame the central courtyard, and the southern side of the west tower is raised on piers to allow natural light into the open space for residents. An onsite wastewater recycling system at the west tower, which filters and treats shower, sink and laundry runoff to tertiary standards, is a pilot project for the UC system and mitigates demand for water in the landscape.
Credit: Spurlock Poirier Landscape Architects

As a result of the project's environmental efforts, the Keeling Apartments achieved LEED-NC Platinum certification from the United States Green Building Council in 2012, and is the first LEED Platinum student housing in the University of California system.

Site Planning Challenges and Solutions
The 158,000-square-foot site is situated at the western edge of the La Jolla mesa, a coastal ridge 400 feet above the Pacific Ocean. Once covered by native coastal sage scrub, the area was planted with eucalyptus groves in the early 1900s. With providential views of the California coastline, the Keeling Apartments site helps define the southwestern gateway to the campus. Importantly, the project is also at the low end of the campus stormwater system, and just above the fragile ecosystem of the Skeleton Canyon outfall to the Pacific Ocean. The project's relationship to this broader system became the most influential aspect of the site design.

The project's construction made the functional aspects of stormwater capture, infiltration and slow release obvious and essential to the campus experience. Buildings, student amenities and open stormwater infrastructure had to be sited thoughtfully to optimize the landscape's benefits, and integrated gracefully to achieve a memorable character. The design team worked to connect building function to the site, so that each works with the other through water conveyance.

Students, visitors and university staff experience the management of stormwater, hear and see runoff moving from roofs and site hardscape through a system of engineered basins and weirs, which releases into a native arroyo bioswale. The intent was to evoke a feeling of connection with the scarcity of stormwater resources in Southern California.

To withstand the salt air, the project incorporates aluminum windows and doors, and stainless steel hardware for exposed elements. Industrial fiberglass grating was incorporated for sunshades, and railing systems were specified for durability in marine environments. The buildings were constructed with high-quality cast-in-place white concrete for durability and consistency with the existing housing architecture.

The architects and landscape architects conducted a detailed analysis of circulation needs, topography, solar aspects and microclimate factors to site the three towers, each five to ten stories. Connected to each other at the sixth floor vegetated roof, the buildings frame a courtyard on the north, west and south sides. The west tower was folded in the plan for solar gain, and its southern half is raised on colums to open the courtyard. Beneath this raised portion, a student meeting room was designed above a dry arroyo bioswale, with fingers extending below the building edges and buffering the west tower from the campus ring road. The arroyo is adjacent to a student event area at the south of the site.

One of the project highlights was on the west tower, a 7,500-square-foot vegetated roof and event terrace that offers views from the mountains to the Pacific Ocean. Framed by a patterned planting of low water-use grasses, perennials and succulents in less than 10 inches of soil, the vegetated roof not only captures and filters stormwater, but also reduces heat island effect and increases the energy efficiency of the building.

The apartments were sited to use prevailing winds and natural ventilation to maximize comfort in both summer and winter. The housing complex offers numerous amenities to students, including two basketball courts, flexible outdoor space, a barbecue station and meeting rooms.

Revealing, Reusing and Conserving Water
Water is a scarce resource in Southern California and requires significant energy to transport from distant sources. Conservation measures incorporated in the Keeling Apartments project include water efficient landscaping, efficient plumbing fixtures and on-site wastewater recycling.

Unique to the west tower is onsite wastewater recycling, providing landscape irrigation water that meets year-round irrigation demand. Filtering and treating shower, sink and laundry runoff to tertiary standards mitigates demand for water in the landscape and reinforces UC San Diego as a leader in sustainability. Strict water quality monitoring also contributes to the scientific research database. The integration of onsite water recycling was a pilot project for the UC system, acting as a legal and technical template for future projects to follow. The north and south towers are integrated in the site's water management program, sending roof runoff down to the stormwater conveyance systems. The central courtyard is the most overt demonstration of this functional and aesthetically pleasing concept: stormwater conveyance channels, designed as a primary axis, visibly guide water flow through the space, celebrating the sights and sounds of rain. Pathways over the channels allow pedestrians to travel the Keeling Apartments without interruption.

Basins, weirs and planted swales manage runoff throughout the complex, which is at the low end of the campus stormwater system, heightening the need for water management. Plantings in the courtyard include coast live oak, California sycamore, Torrey pines, "forest pansy' eastern redbuds, Douglas iris and St. Augustine turfgrass.

Two gently sloped lawns provide opportunities for lounging, and also accept water through conveyance channels that carry flows from the building roofs and site, creating ephemeral pools. The pools are designed for maximum revelatory effect, capturing and slowly releasing volumes up to a 100-year storm event. When this happens, runoff water spills to the arroyo bioswale filter before releasing to the Skeleton Canyon outfall. The arroyo bioswale filters pollutants and captures suspended sediments from the large parking areas east of the site. The bioswale does significant heavy lifting, improving water quality and decreasing the quantity carried to the outfall. Plants in the arroyo were selected from endemic palettes for their drought-tolerance and ability to accommodate periodic inundation. The low water native landscaping in the bioswales extends habitat opportunities to fauna located in nearby California coastal sage and chaparral ecosystems, and creates a natural landscape buffer between roadways and the buildings and amenity space at the Keeling Apartments. As a whole, the stormwater management and conservation practices on site evoke a feeling of connection with the scarcity and importance of water in Southern California. The Keeling Apartments were also oriented to take advantage of the solar aspect and prevailing winds, using natural ventilation to maximize comfort in both summer and winter. Within the courtyard, the shadier microclimate demanded selections of low water shade-loving natives and adapted species.

The arroyo bioswale, adjacent to a student event area at the south side of the site, improves water quality and decreases the amount of runoff carried to the Skeleton Canyon outfall. Plantings, which include "Yankee Point' and "Julia Phelps' Ceanothus, San Diego sedge, knife leaf acacia, deer grass, California gray rush, dwarf coyote bush, vanilla trumpet vine and Bush Island snapdragon, were selected for their drought-tolerance and ability to accommodate periodic rain events.

Resident Response
The environmental elements of the project, including the vegetated roof, gray-water irrigation, stormwater infiltration and native plants, enhance student life through everyday engagement with natural processes. The Keeling Apartments encourage occupants to actively use the outdoor space, as students now have many areas conducive to gathering. For example, the event area was designed to include an outdoor barbecue, flexible spaces and two basketball courts.

Thankfully, second-year students at Revelle College are no longer disconnected from their peers. In addition to the housing and surrounding outdoor amenities, these students have easy access to the main dining facility, classrooms and can engage in the greater UC San Diego community, with extracurricular activities and other campus happenings.

The site manages 100 percent of on-site precipitation, providing bioretention and bioremediation, the latter via a system that includes the vegetated roof, downspouts, channels and retention basins. The system's integration reduced stormwater quantity, delayed peak water flow and controlled flooding in this region of the campus.

Industry Response
In addition to its LEED certification, the project was named one of the Top Ten Green Projects by American Institute of Architects and its Committee on the Environment; earned the coveted President's Award from the American Society of Landscape Architects, San Diego Chapter; and won an American Society of Civil Engineer award of merit in sustainable technology.

The stormwater system was designed to control potential flooding, and can capture and slow-release water levels up to a 100-year storm event. During heavy rains, overflow from the green roof is directed to the courtyard retention basins, allowing sediment and pollutants to settle and filter out before water leaves the site.

Team List
Client: University of California, San Diego
Architect: Kieran Timberlake Architecture
Civil Engineer: Nasland Engineering
Construction Manager: Swinerton Builders
Cost Estimating: International Consultants, Inc.
Electrical Engineer: Sparling
Environmental Consultant: Atelier Ten
Landscape Architect: Spurlock Poirier Landscape Architects
Lighting Consultant: Candela
Mechanical, Plumbing & Fire Protection: IBE Consulting Engineers
Photographer: Tim Griffith
Specifications Consultant: Technical Resources Consultant Inc. (TRC)
Structural Engineer: John A. Martin & Associates

The west tower also features a 7,500-square-foot green roof, designed by Spurlock Poirier Landscape Architects, that incorporates a patterned planting of low water-use grasses, perennials and succulents in less than 10 inches of soil. More than 4,000 plants capture and filter stormwater, provide thermal insulation, reduce heat island effect and increase the building's energy efficiency.