UNC Greensboro Aquatics Go Green

There is a growing trend among athletic aquatic facilities to install eco-friendly pool equipment designed to lower operating costs by lowering energy consumption. Swimming pool pump rooms are among the areas most scrutinized when facilities undergo energy audits due to the amount of energy consumed by pumps, filters and even pool lighting. The University of North Carolina in Greensboro (UNCG) was updating its aquatic center and not only wanted to redesign the facility to better serve the needs of the population it serves, but also wanted to do so with the most energy-efficient equipment to control operating costs.

UNCG, like many universities, needed to improve its student recreation and wellness centers. This trend began about 10 years ago with the explosion of the "arms race" of student recreation centers—as recreation centers became more architecturally attractive with facilities that are used as showcase facilities to attract new students. An awareness grew that not only is physical health important but mental and emotional health are just as important to the student body. This changed the old-school gyms with weights and tracks into all-encompassing wellness centers with social centers, dieticians, counselors and spaces to do physical activity.

The Design

In the case of UNCG, there was a student-led referendum and bond for the creation of the Kaplan center for wellness. RDG Planning & Design was the architect of record, and Aquatic Design Group worked closely with the architect to create this space that met all the criteria required by the university. The contactor selected for the building of the pools was Paddock.

The aquatic center is an indoor facility with large windows comprised of two separate bodies of water. A larger, 25-meter swimming pool for lap swimming and other aquatic activities and a second leisure pool that offers several unique features that provide social and leisure desired by the student community.

The Big Pool

The university does not have a competitive swim team. As a result, in lieu of a regulation competitive pool, a 25-by-25-foot pool was built to allow for lap swimming, as well as programming like kayaking, scuba and paddle-boarding courses. In addition, this pool can be rented out for community swim meets, providing additional income for the center while also actively engaging the community.

The Leisure Pool

The students also wanted the aquatic facility to embody more of a resort feel, and thus the leisure pool was created with many typical resort-style features, such as a water lounge ledge where students and faculty can sit in water but still work on their tablets or mobile devices. "In addition we included a vortex feature, which is a semi-circle in which the water moves around creating a type of current for users to walk against the current," said Justin Caron, principal at Aquatic Design Group. Caron explained that the feature is unique because the vortex/current can be turned on or off as desired. This allows users to do physical therapy when walking against the current. When the feature is turned off, the area remains a calm, shallow body of water in which people can lounge.

In fact, a seat bench was designed into this area and it faces a large video board where movies and sports are shown, allowing users to sit in the leisure pool to watch the video board. The video board also features school announcements and the like, and doubles as a scoreboard when the university hosts local community swim meets for high school and younger ages.

The leisure pool also has an ADA-compliant beach entry that was designed with curves into the pool partly because of a lack of deck space. It works well not only because it's ADA compliant, but helpful to people with mobility issues, injury or those who just want to enter the water slowly.

The leisure pool also includes a basketball hoop and a volleyball net designed to create that fun, resort-like atmosphere.

The Pump Room

The pump room was placed beneath the pools in order to save energy. Pumps are great at pushing water up and pull water down poorly. Therefore, by putting the pump room below the pool, the water flows downward using gravity rather than power. Known as a flooded suction pump design, this type of pump and system is able to reduce its energy consumption by more than 50 percent compared to a self-priming pump system.

The equipment used in the pump room all contributed to the LEED Gold rating for the facility. Aquatic Design Group always works to create the most energy-efficient and most water-efficient systems possible within the constraints of the project.

As with all new aquatic centers, the equipment selected to operate the pools is key to the long-term success of the facility. "We used very specific criteria when selecting the pump room equipment," said Caron. In evaluating each piece of equipment, Aquatic Design Group applied three main criteria:

1. Local availability: not only its proximity to the facility itself, but how easily the equipment can be serviced, and how readily available parts are available for equipment maintenance.
2. Warranties on each piece of pump room equipment
3. Overall life-cycle costs, from the front-end costs to the efficiency of operation and life expectancy of the equipment.

In this case, much of the equipment specified and used was supplied by Pentair. "The equipment met our three criteria being in close proximity to UNCG, offers excellent warranties and provided the best value according to our calculations," Caron said.

As always, this project went through the public bid process and Paddock Pools was awarded the job. In addition to the items originally specified, Paddock also added their stainless steel gutter and air handling systems.

Energy Efficiency

Like many university aquatic facilities undergoing updates, the new UNCG pools were equipped specifically with energy-saving equipment in order to reduce energy consumption by their swimming pools and thus reduce operating costs. The main energy saving products used included the Acu Drive XS Variable Frequency Drives (VFDs), Stark Filter systems and IntelliBrite 5G LED pool lights.

The VFD is designed specifically to help aquatic facilities save energy and operating costs by increasing pump performance, saving up to 60 percent or more on the pump's electricity usage. The VFD allows the system to ramp up to full speed during the day when the pool reaches peak bather loads. At night, the drive can slow the pump down to continue filtration but not at full speed while closed. The VFD units have a minimal payback time as they automatically optimize energy. In fact, the VFD units offer a built-in display to show how much time remains until the drive pays for itself. Many utility providers around the country even offer rebates to those that install a variable frequency drive—making the investment in the drive minimal.

"The VFD is the ideal piece of equipment for controlling costs associated with the energy needed to run the pool pumps," Caron said. "VFD units eliminate energy spikes to reduce energy consumption and also help the pump motors run smoother and last longer, as they eliminate the wear and tear associated with starting and stopping. VFDs are part of our energy-saving best practices and have become standard in our pump room designs."

The UNCG facility also installed two sand filter systems. The competition pool has one system comprised of three filter tanks plus a separate two-tank system for the leisure pool. These systems have an integrated automatic backwash control system that makes them highly energy-efficient. The filters are easier to install and maintain because they have a modular design that allows for influent and effluent placement to meet any design requirements. In this case, a side-by-side configuration was chosen. These new green units were chosen for this particular pump room because they occupy as little as one-fourth the floor space of other filters. The filters were ideal for this pump room located below the pools themselves in a relatively tight space. The manway viewport on the front of the filters provides a quick, visual observation of the sand bed during filtration and backwash that allows for better monitoring and maintenance. In fact, the difference between a clean and dirty filter can nearly double the pump's energy consumption, so checking the sand bed frequently is crucial.

Choosing LED lighting is a very important part of the overall plan to reduce energy consumption. Old incandescent lights are inefficient and don't provide the best illumination. Changing aquatic facility lights to LED technology immediately lower electrical bills and maintenance staff will rarely need to change those bulbs. The facility's LED pool lights use 89 percent less electricity than incandescent and halogen pool lights. LED circuits are extremely energy-efficient, and because each light lasts much longer, the bulbs are changed less frequently, providing aquatic facilities additional savings over time.

The End Result

The Kaplan Aquatic Center is now open and running efficiently. The pools meet all the needs of the students, faculty and community. The air quality system has created a superior indoor environment and the green pump room design and equipment ensure that the facility keeps operating costs lower so more funds are available for well programming or other facility improvements.