LEED BD+C: New Construction v2 - LEED 2.2
Salt River Fields at Talking Stick
LEED Gold 2011
The below stakeholder perspectives address the following LEED credits:
SSc2, SSc4.4, SSc5.2, SSc6.1, SSc6.2, SSc7.1, EAc1, WEc1, WEc3, IEQc2, IEQc6.2
* This profile has been peer-reviewed by a USGBC-selected team of technical experts.
Goals and motivations
What were the top overarching goals and objectives?
Our overall goal was to support the owner's desire to have a facility that represents the culture and values of their community. Many of the LEED elements are a perfect fit with the ideals of the Indian community. The Indian community can educate others on their culture by having a facility with a type of certification that others will understand.
What were the motivations to pursue LEED certification and how did they influence the project?
- Design innovation
- Integrated design process
- Organizational policy
- Organizational priority
The examples above were all motivating factors but, more importantly, we felt compelled to pursue LEED certification because of the educational value associated with the certification. Hundreds of thousands of fans visit our venue annually, and Salt River Fields at Talking Stick will hopefully teach and inspire our visitors to make changes in their own day-to-day behaviors, at work and at home, all with an eye on improving their own sustainable operations.
What were the most notable strategies used to earn LEED credits?
Selecting the right site was an important strategy for this project. We sited Salt River Fields on a previously-developed golf course that is within walking distance of residential zones and basic services, helping earn Sustainable Sites credit 2. The location is highly visible from the 101 freeway and has four main entrance points. Connecting the surrounding area to the ballpark, including nearby suburban retail development, via pedestrian access was a vital strategy. There is a lot of suburban retail development around the site and we liked that this encouraged pedestrian use to the stadium. Other sites that the project team considered were on the outskirts of town, had one freeway point, and didn't really have development around them. The project team saw this stadium as a step in revitalizing the area, including the adjacent outdoor shopping mall, by bringing business with the spring training folks and other site events. We were also able to take advantage of the opportunity for shared parking with the shopping mall to alleviate some pressure on our site.
Opening day of the 2011 Spring Training season attracted over 12,500 people to Salt River Fields.
When looking at the LEED development density and community connectivity credits, we started to overlay the half-mile walking radiuses over the multiple entries. With four major entries into our site, we had four different radii. Given the 140-acre site size, the half-mile walking distance radius incorporated a lot of our site and didn't reach out of our boundary as much as I hoped it would. But we were still able to achieve Sustainable Sites credit 2 Development Density & Community Connectivity with ten nearby services, while being close enough to the residential neighborhoods.
Listen to HKS LEED project administrator Ellen Mitchell discuss the challenges and solutions with documenting the use of the baseball field as alternative parking.
What cutting-edge strategies or processes were implemented?
The project incorporated a significant number of energy efficient design strategies including dual-pane glazing systems with low solar heat gain properties, variable air volume water-cooled air conditioning systems with variable speed pumping and cooling tower systems to provide the most efficient system demand response, and evaporative cooling strategies to select areas to eliminate the need for mechanical refrigeration. The most cutting-edge of these many strategies, however, is the use of displacement ventilation air distribution throughout the two clubhouse buildings and most notably in the major and minor league locker rooms.
Interior photograph of the Arizona Diamondbacks clubouse. Design strategies featured including maximizing the amount of daylight in the perimeter spaces as well as underfloor air vents.
Displacement ventilation is a departure from the traditional overhead air distribution air conditioning systems we often see. Rather than providing conditioned air at the ceiling level which requires mixing the entire air volume of the space to achieve an acceptable level of occupant comfort, displacement ventilation supplies relatively neutral temperature air at low level and low velocity to take advantage of the natural stratification within the space. The primary benefits are:
- Reduced energy consumption by the central HVAC systems as air is cooled only to 65 degrees F rather than 55 degrees F with a traditional overhead system. The increased air temperature also allows an increase in the number of economizer hours available to the HVAC systems.
- Reduced fan energy as the system conditions only the occupied space and not the entire room volume as a traditional overhead system does.
- Increased occupant comfort with less draft risk coupled with improvements in the indoor environment. Contaminants within the occupied space rise with the stratified return air and are removed from the space in contrast to a traditional overhead system where contaminants are continually mixed in with the supply air as the whole volume of the space is conditioned. In a locker room environment, where air quality is of particular importance, this strategy provides a significant environmental quality improvement.
The project required a very collaborative effort among all parties on the design and construction teams and the integration of displacement ventilation into the locker rooms is a prime example of this effort. The air supply is integrated into the 6" base of the player lockers, creating a very clean, and well hidden, final product. Supply ductwork from above the ceiling runs down to the locker bases, hidden within column furring and in corners between lockers, where it pressurizes the architectural plenum created by the locker base assembly. In order to ensure the system's performance in the small physical space available within the locker bases, the design team modeled the proposed installation and the contracting team performed smoke tests after installation which confirmed the design team's airflow modeling results and the air-tight integrity of the field fabricated locker bases.
Listen to HKS project manager Andy Henning describe the decision to use an underfloor air distribution system on the Salt River Fields project.
How was the integrative process applied and what was the greatest benefit gained?
Although the integrative process was not specifically applied to the Salt River Fields project, the nature of the fast-track schedule ultimately required an incredibly collaborative approach that mirrored an integrative process in many ways. Because the project had three clients - the Salt River Pima - Maricopa Indian Community, the Arizona Diamondbacks, and the Colorado Rockies - an integrated approach of some form was the only method that all parties felt would be effective and lead to a successful outcome. The collaboration required a high level of dedication and commitment by all involved. A focused effort was made to ensure that all meetings took place with all parties present. Because the architect, owner, and all three user groups were spread across the country several hours from one another, this approach required going the extra mile to fly to a single meeting location. Meetings took place every other week for nearly a year. In the end, the results proved the effort made by all parties was more than worth it.
The greatest benefit gained from the collaborative process was the distinct values and points of view that each group brought to the table. The Salt River Pima - Maricopa Indian Community emphasized its cultural appreciation for the land and the history of baseball within their community. The Arizona Diamondbacks were committed to celebrating achievement and creating a family-friendly atmosphere that allowed for a connection to baseball training not provided before. The Colorado Rockies stressed the importance of demonstrating what it took to be a team and the importance of relationships in both baseball and life. With each organization focused on very different ideas and objectives, teamwork led to a facility that was well-rounded and stronger in every way.
It was an interesting learning experience for the Indian community. They came into the project thinking that LEED came with an added expense, but as we got into the design standards, they were fully on board. It translated directly into the design processes when they realized that the practices we were already planning got us to the Gold certification level. It's exactly what the Indian community and baseball teams wanted; they just didn't realize they could get it as part of a more traditional approach.
The exterior of the Colorado Rockies clubhouse illustrates the desire to maximize the amount of daylighting in the space while using a terra cotta rainscreen to block the sun.
A specific example of the integrative approach was one critical project team discussion in regards to the clubhouse faucets. We had designed the faucets as motion-activated, which was a large concern since the players wanted hot water consistently running for shaving needs. In the end, they sacrificed this desire. It may not sound like a large sacrifice, but it was an intense conversation to get them to agree to the motion-activated faucets. It really showed a large commitment to sustainability on the part of the stakeholders to encourage the players to adjust their habitats in the interest of conservation.
Aside from LEED certification, what do you consider key project successes?
Beyond LEED certification, one of many additional project successes was developing a design in tune with the unique site conditions for an unprecedented client, a Major League Baseball Spring Training Complex. Salt River Fields at Talking Stick represents the first Major League Baseball facility constructed on Native American land. The Salt River Pima-Maricopa Indian community challenged the design team to create a spring training home for the Arizona Diamondbacks and Colorado Rockies that spoke the language of not only the land that is was to be constructed on, but also the Indian community responsible for its creation. The result was a spring training facility that not only responded to a unique landscape and client goals, but more importantly, brought attention and focus to them.
The facility is not just a baseball park, but a park for the community, and that was part of the design intent. Outside of the baseball season, the facility manager and his team host nearly 170 events at the facility, including art shows, wine tastings, and concerts. Additionally, the Indian community uses the dance ring for pow wows, including community gatherings, dancing festivities, and arts and crafts shows.
The inclusion of native and adaptive vegetation throughout the site and within the stadium was a key design driver for the SRP-MIC.
An additional project success can be found in the high level of baseball immersion for visiting fans, created by the design. Training activities that traditionally take place behind the scenes (such as batting cage hitting and catcher drills) are celebrated by being brought front and center, so fans can see them up close and personal and interact with the players.
Water conservation in an arid environment such as Phoenix is always a challenge. This challenge was difficult to overcome due to the necessity of numerous grass practice fields. Irrigation is re-circulated from a lake that was created to gather rainwater on site. We're allowing the natural rejuvenation of that lake, as well as using it for irrigation. Irrigation is also augmented by well water, which on this site is designated potable. Although LEED credits for water reduction through irrigation were not feasible, we counter-balanced this by incorporating extensive areas of open space that weave between practice fields, parking lots, clubhouses, and even the stadium. This open space, vegetated by a native and low water-demanding Arizona plant palette, became an amenity not often found at a facility like this. The design team viewed this open space incorporation as healing the land by reintroducing its natural processes, while the baseball components exist cohesively within a native environment, enriching the experience of visitors and players alike.
One of the 4 main entrances to Salt River Fields highlighting the use of native landscaping.
We were very fortunate to have an owner and client who have a deep connection to the land. The site had some mature vegetation prior to construction, offering an opportunity to preserve native plants. We identified plant material that could be harvested and boxed it, storing it on-site during major construction. We inventoried the plants when they were in place prior to harvesting, and then again after being boxed and stored. After construction, we replanted the vegetation within the project site. It was a real benefit to the project aesthetically because it's so unusual to have such large mature species on day one. This plant relocation meant the site had large, mature species on day one, which also provided related shade benefits. It also helped maintain those micro-climates that the harsh sun requires to uphold the normal ecological benefits in our local ecosystem.
Mature cacti and plant relocation
What were the most important long- and short-term value-add strategies and what returns on investment (ROI) have been experienced or anticipated?
We monitor the social media feedback surrounding the site and it's been amazing how much positive feedback we have been getting through Twitter, Facebook, and other sites. What's even more impressive is the record that the Diamondbacks and Rockies set last year: They had an attendance record that shattered the Cactus League spring training records; their average of 11,000 to 12,000 attendees per event was more than twice that of other facilities.
The newness is not wearing off, as this year has been similar. They've had three to four events so far and the attendance numbers have been similar (over 12,000 people for each one). People have commented on the LEED certification and the appreciation they see in the stadium's design for the land, as well as the spectators (particularly the solar angles that offer shaded seating).
What project challenges became important lessons learned?
Being a somewhat unique project type within the LEED system, there were challenges that were difficult to overcome and credits that were not achievable. Two perfect examples are irrigation and light pollution.
As a Major League Baseball facility, there are certain watering requirements for playing and practice fields that can be water-intensive. Due to the project's location, it was not possible to harvest enough rainwater to meet the watering requirements. The project team tried to balance the large amount of potable water needed for the fields by integrating native, drought-tolerant plants that required no irrigation throughout the rest of the site.
Drought tolerant native plants awaiting relocation
Because of budget challenges, landscaping also took a hit. Rather than eliminate landscaping, the strategy was to reduce the maturity of the landscape. The design team was forced to make some cuts to fit in the budget. One option was to reduce the amount of plants in the design, which would have affected the potential for shade and species habitat, not to mention aesthetics. Instead, the team chose to keep their original plant palette, but purchase smaller, younger plants because they are less expensive. This way the original landscape design was not compromised, but would simply take an additional three to five years to reach the maturity level of the initial design. We also looked at ways to reduce plant densities. Working with civil engineers on how we were going to handle stormwater early on in the project played a large role in the comfort level with reducing densities and maturity levels. We had the chance to reintroduce the natural process of water flow in the desert rather than piping water underground or dumping it straight into a sterile retention basin, which gave us comfort with those compromises and also meant less maintenance was required in the future because the landscape functioned in a more natural way. These compromises required some convincing of the ownership, but by doing this, we saved the money we needed to and also saved the design.
Likewise, the stadium lighting that was required for night games and practices came nowhere near meeting LEED's dark sky requirements for reducing light pollution. As the exterior lighting was a "necessary evil" for the venue, the design team again tried to offset it as much as possible by reducing the lighting power density within the clubhouses and maximizing the amount of daylight entering both facilities.
What was a pivotal moment that impacted the project's direction?
A key moment in the development of the Salt River Fields project surfaced early in design when it was determined that a significant budget challenge existed. The value engineering process led to the loss of two key environmental strategies that were contemplated early on in the project: geothermal energy applications and evaporative cooling concepts. The loss of these concepts led to the implementation of other important design decisions that eventually drove many of the major factors associated with the project as a whole.
One example was the orientation of the baseball stadium itself. To create the greatest opportunity for passive cooling concepts wherever possible, we oriented the stadium in a manner that placed occupied interior space in shade wherever possible. In doing so, the stadium volume was used in a way that it cast the most effective shadow possible on the exterior seating of the stadium seating bowl. In the end, the ballpark design achieved shade across nearly 85% of the outdoor seating throughout the traditional timeframe of a spring training baseball game.
The roof was a prominent design feature and oriented for maximum possible shade for the concourse and stadium seating.
In addition to orientation, the roof design of the ballpark and baseball administrative offices was greatly influenced by the loss of geothermal energy applications and evaporative cooling concepts. Large roof overhangs were incorporated into many elements of the facility to allow for a large expanse of glass, as desired by the clients, while avoiding transmission of heat to interior spaces because the sun did not contact glass surfaces. This design strategy coordinated seamlessly with the goals of the Salt River Pima - Maricopa Indian Community due to the predominant use of "ramada" shade structures for cooling throughout its history.
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