The Mercy West Lakes Hospital is a seven story, 85 bed facility in West Des Moines, Iowa. There is approximately 250,000 square feet of finished space with another 70,000 square feet of enclosed shell space for future expansion. It incorporates the following services: cafeteria, kitchen, administrative offices, helipad, six operating rooms, a labor and delivery area, two C-section rooms, MRI, CT scan, X-ray, cath lab, emergency department, two trauma rooms, bariatrics, ICU, pharmacy, decontamination area, and centralized lab facilities. Additionally, there is a separate central plant housing all major mechanical equipment and a 120,000 square foot, two-story parking ramp. Tunnels connect both structures to the main hospital building. This hospital is designed to achieve the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) Certified rating.

All major mechanical equipment is housed in a separate central plant, remote from the hospital. Piping for all utilities is routed through a utility tunnel to the hospital. The chilled water system consists of two 650 ton water cooled chillers. Both units are equipped with auxiliary condenser bundles to preheat the domestic hot water. The chilled water system is a variable primary flow system. There is also a separate 140 ton air cooled chiller with glycol to maintain discharge air temperatures and humidity levels required for the surgery rooms.

The heating water system consists of three steam boilers, two 500 BHP and one 250 BHP. The boilers are equipped with dual fuel burners to utilize natural gas or fuel oil. 75 lb steam is produced and piped to the basement mechanical room in the hospital. Heating water for the building is generated by two steam-to-hot water heat exchangers. Heating water is utilized in the air handling units, fan coil units, cabinet unit heaters and VAV boxes. The steam is also used for sterilizers, humidifiers, kitchen equipment, and making domestic water.

The HVAC design is a variable air volume system utilizing six custom air handling units providing a total of 350,000 cfm of air to the building. Space temperature is maintained by terminal air boxes with hot water heating coils. All AHU’s incorporate heating and chilled water coils, air blenders, direct inject steam humidifiers, sound traps, and UV lights. Medical gases are distributed throughout the hospital. Systems include oxygen, nitrogen, nitrous oxide, carbon dioxide, medical air, instrument air, waste anesthesia gas, and vacuum.