With 18 million square feet (1,672,200 m2) on 67acres (27 hectares), MGM MIRAGE’s CityCenter development in Las Vegas is one of the world’s largest environmentally sustainable developments to receive LEED certifications from the Washington, D.C.-based U.S. Green Building Council.
With six LEED Gold certified buildings—ARIA Resort & Casino; Vdara Hotel & Spa; Mandarin Oriental, Las Vegas; Veer Towers; and Crystals retail and entertainment district—CityCenter is the highest LEED achievement of any hotel, retail district or residential development in Las Vegas. The Harmon Hotel, opening later this year, is also expected to receive LEED Gold certification. Additionally, ARIA is one of the first Las Vegas hotels to achieve LEED Gold certification and is currently the largest hotel in the world with LEED Gold status.
More than 60 LEED Accredited Professionals from across the United States contributed their expertise over CityCenter’s five-year design and construction process.
“When we started, this was the largest, and still is, the largest registered or LEED certified project in U.S. history. But also when we started it [in 2005], the square footage—18 million square feet of CityCenter was as much square footage as all other LEED projects combined, either registered or certified,” said JF Finn, principal, Gensler, San Francisco, and CityCenter project executive.
“Not only is CityCenter one of the most ambitious developments ever built, it is an industry leader in design complexity, environmental sustainability, construction diversity participation and manpower,” said Craig Shaw, president and CEO of Perini Building Co., Henderson, Nev., the general contractor.
LEEDing the Way
“From its inception to design, development and construction, we had one single goal in mind for CityCenter: create a destination that is not only built in an environmentally sustainable manner, but also operates every day with an equal commitment to conserving natural resources,” said Bobby Baldwin, president and CEO of CityCenter.
“[City Center] was one of the first projects to really be from the resort owner side; to take a leap out there and say we are going to do a sustainable project, we are going to go after LEED Silver or Gold or better,” Finn said. “And [MGM MIRAGE] made that a public and very strong initiative as one of their core objectives in the development; they were the first ones to do it.”
Cindy Ortega, MGM MIRAGE’s senior vice president of energy and environmental services, led a collaborative effort between the general contractor, Perini Building Co., the entire design team, subcontractors, consultants, and hundreds of manufacturers and suppliers, to achieve MGM MIRAGE’s vision of creating a sustainable environment.
Perini had a significant impact on earning LEED certification, managing the LEED compliance for more than $1 billion worth of building materials. Perini’s sustainable efforts included construction waste management, site pollution prevention, indoor air quality, regional and recycled content material procurement, and the use of Forest Stewardship Council wood.
During preconstruction, Perini gathered data, provided client feedback and suggested options for pursuing the most material-based credits in cost effective ways. The preconstruction and LEED teams collaborated to model costs for building components, site-based management plans and building systems relative to Forest Stewardship Council certified wood, construction management and indoorair quality management throughout construction.
Perini developed and maintained systems for tracking and documenting LEED credits on the project, and offered formal training sessions for its own staff and 250 subcontractors, assisting with the research and procurement of sustainable materials and implementing proper LEED documentation.
“CityCenter captures the energy and diversity of Las Vegas in one of the world’s largest green developments,” said Jim Murren, chairman and CEO of MGM MIRAGE. “Designing CityCenter with sustainable elements and practices reinforces its permanence and creates a healthier environment for our guests and residents, as well as for the 12,000people who work at CityCenter.”
Modeling Efficient Design
CityCenter’s efficient design saves the amount of energy equivalent to the average annual power use of 8,800 homes. To create the most sustainable buildings of this era, the project features complex window glazing, building shades, and light-colored rooftops that reflect and deflect the intense desert sunlight before it can enter buildings, dramatically reducing the amount of energy required to cool indoor spaces.
To achieve a 30 percent increase in energy efficiency over similar buildings using traditional design, a state-of-the-art central power plant allows CityCenter to generate its own electricity on-site.The power plant uses natural gas to create electricity, and then captures emitted heat before it enters the atmosphere to meet the domestic hot water needs of all the buildings and pools in the complex.
Low-wattage lighting, along with compact fluorescent bulbs, LEDs and cold cathode light systems are used throughout the project. Every condominium unit features Energy Star washers, dishwashers and refrigerators.
Combined with periodic building inspections,computerized control systems provide constant electronic monitoring to ensure that all systems are performing at optimum capacity and maximizingenergy conservation.
Water Usage
To save nearly 50 million gallons (190 million liters) of water each year, or the equivalent to the amount of water used annually by 380 Las Vegas homes, CityCenter utilizes advanced plumbing design and low-flow technologies. Low-flow showerheads, faucets and toilets that were chosen by designers to deliver water savings of more than 30 percent compared to standard bathroom fixtures.
During construction, reclaimed water from Monte Carlo’s cooling tower was used to control dust, saving 2.4 million gallons (9,120,000 liters) of potable water and the energy required to process and pump it. Soil surfactant and tackifier was used to lessen the occurrence of stockpiled and unimproved surface dirt becoming airborne.
Native and drought-tolerant species were utilized throughout CityCenter’s landscaping for their heat and low-water tolerance. Additionally, moisture-controlled sensors and other technologies ensure that landscaping is irrigated only as needed, resulting in the exterior vegetation using 60 percent less water than traditional landscapes.
Indoor Air Quality
A stringent indoor air quality plan was implemented during construction to ensure a healthier environment and maximize the well being of CityCenter guests and residents. Non-toxic paints, sealants, adhesives, carpet and composite wood products were utilized during construction, and also for touchups and renovations. Additionally, Perini procured and installed low-emitting Carpet and Rug Institute Green Label Certified carpet pad.
Construction workers were limited to designated smoking areas, protecting the air quality in guest rooms and eliminating the potential for the wallpaper and carpet to absorb tobacco smoke. All hotel rooms and residences were sealed to prevent the migration of tobacco smoke between units.
Recycling and Waste Management
At the onset of the project, the CityCenter team developed a strict construction waste management program that redirected recyclable and reusable resources back into the manufacturing process, diverting more than 94 percent of the construction debris from landfills. Overall, more than 295,000 tons (265,500 metric tons) of waste was hauled from the site, with more than 276,000 tons (248,400 metric tons) diverted from landfills. Additionally, 82 tons (74 metric tons) of used wood were donated to the local Carpenters Apprenticeship training center.
A Perini subcontractor used a B20 blend of biodiesel in the equipment for site work and excavation. Perini tracked and reported the totals of biodiesel used, resulting in the award of a LEED Innovation Credit for reducing carbon emissions and utilizing local yellow food grease that is otherwise sent to a landfill.
More than 80 percent of the imploded Boardwalk Hotel and Casino was recycled or reused, including doors, hardware, scrap steel, other metals and carpet was sold to resellers; broken tiles, concrete and asphalt were taken off-site, crushed and made ready for reuse as backfill or underlayment; and salvaged toilets and countertops were donated for reuse.
Throughout construction, 1.3 million cubic yards (988,000 cubic meters) of dirt and caliche removed from the site, or enough to fill 16,000 residential swimming pools.
More than 289,000 tons (260,100 metric tons) of waste, or the equivalent of 193,000 Honda Accords, were also hauled away.
CityCenter uses four recycling docks to separate and collect recyclable materials, such as paper, cardboard, plastics, glass, metals, kitchen grease and other commodities.
Materials
Building a project of this scale to LEED standards helped support the local economy by procuring more than 48 percent of the LEED tracked materials from within 500 miles (800 km) of CityCenter. More than 18 percent of the material was harvested, extracted or recovered within the same 500- mile radius, including the majority of the drywall sourcing and the majority of the millwork and cabinetry manufacturing.
CityCenter sought and utilized the products of more than 260 manufacturers located within a 500- mile radius of the site. Designers chose products manufactured with recycled content to reduce the exploitation of virgin resources, while also seeking local and regional products to minimize the emission of greenhouse gases generated during transport and delivery.
CityCenter created a market for Forest Stewardship Council certified wood use in Las Vegas. Perini and its subcontractors procured more than 91 percent of the total wood for ARIA and Crystal through FSC chain-of-custody certified suppliers and manufacturers. The FSC wood products came from more than 85 FSC certified mills, material vendors, suppliers, distributors, manufacturers and fabricators.
Fly ash was used as a cement replacement in more than 1 million cy, with an average of 4 percent mixes by weight. CityCenter achieved 26 percent recycled content for all applicable construction materials. By replacing an average of 17 percent of cement with fly ash, the project was able to reduce carbon emissions by 119 million pounds (53,550,000 kg).
By allocated space for an on-site concrete production plant, CityCenter managed to greatly reduce mileage traveled by trucks to deliver thousands of loads of concrete to the site. All raw materials used for concrete manufacturing were extracted from within 500 miles.
Additionally, material suppliers and manufacturers that worked or bid on CityCenter were required to document the origins and composition of their products, gaining experience in sustainable projects transferable to future projects. CityCenter’s magnitude assisted an emerging waste management trend in the Las Vegas area, influenced market attitudes and is viewed as a model for sustainable design and construction.
Driving Forward
CityCenter also commissioned the world’s first stretch-limo fleet powered by compressed natural gas. Developed by Krystal Enterprises, Brea, Calif., in collaboration with Seal Beach, Calif.-based Clean Energy Fuels, Dallas-based BAF Technologies and Dearborn, Mich.-based Ford engineers, the 26 silver, 24-foot (7-m) Lincoln Town Cars are 100 percent dedicated to utilizing CNG. The cars will service the ARIA Resort & Casino and Vdara Hotel & Spa.
“Commissioning the first CNG stretch-limo fleet is a demonstration of CityCenter’s commitment to environmental responsibility, while never sacrificing guest experience,” said Bill McBeath, president and COO of ARIA Resort & Casino. “Just as with every element of CityCenter’s design and construction, we’re determined to employ the most innovative solutions possible to grow responsibly, while continuing to raise the bar on service, comfort and experience.”
Compressed natural gas was selected because of the U.S. natural gas reserves. It is also one of the cleanest burning alternative fuels available and is generally less expensive than either gasoline or diesel with greater price stability.
Guests at CityCenter also receive preferred parking for hybrid or electric cars and carpoolers, and are offered bicycle valet service. Residents have bicycle storage, rideshare options and dedicated carpool pickup lanes, while employees are presented with a full range of transit, bicycle, green car and carpool options.
“MGM MIRAGE’s initiative to build such an unprecedented environmentally sustainable project has changed the Las Vegas construction and the hospitality industry,” Shaw said. “There is a new level of understanding of the importance of environmentally responsible construction. The commitment of all of the entities involved to achieve LEED at this level has been one of the most rewarding aspects of this monumental project.”
