THE Water Down Under.

The host facility for the aquatic events of the 2000 Summer Games in Sydney, Australia, is using a state-of-the-art water chemistry control to provide consistent, high-quality pool water.

With the dawning of a new millennium, the eyes of the world will be focused on Sydney, Australia, host city of the 2000 Olympic Games. Preparations are well under way to ensure an event worthy of showcasing this splendid city. As the centerpiece of the Homebush Bay Olympic site and host to all aquatic events, the Sydney International Aquatic Centre is already living up to its reputation. Juan Antonio Samaranch, president of the International Olympic Committee, described the facility as, "The best swimming pool I have seen in my life." Opened to the public in October 1994, more than 300,000 people passed through its doors in the first three months of operation.

Green and Clean

Because the 2000 Olympics are being dubbed the Green Games, focusing on environmentally sound principles for swimming pool operation and maintenance was obviously important. From the use of gas for heating pool water to minimizing chemical usage for water treatment, the SIAC is committed to protecting the environment whenever possible.

The Olympic aquatic facility contains four pools: a 50-meter, 10-lane competition pool; a 50-meter training pool with a movable floor; a utility/diving pool; and a leisure pool with separate spas. More than 10 million liters of water fill the four pools. And, considering factors such as swimmer comfort, sanitation requirements, and the advances that have been made in underwater photography, it is critical that water chemistry be at a perfect balance throughout the Olympic aquatic events.

The competition pool was designed with an emphasis on achieving faster swimming-event times. Wetdeck water returns on each side of the competition pool reduce reflected wave patterns. A 2-meter minimum depth throughout the pool guarantees reduced turbulence and ensures that special attention has been paid to the slope of the foot- and handgrips on the starting blocks. A movable, motorized bulkhead enables the competition pool to be divided into two 25-meter short-course competition pools at any time.

The utility pool is 3 to 5 meters deep and is designed to accommodate a 10-lane, 25-meter short-course event, a water polo match, or swimming/diving training. The dive tower is built to the latest design standards and according to Olympic specifications.

The 50-meter training pool features an adjustable-depth movable floor, which covers more than two-thirds of the pool's length. The floor is moved by mechanically tensioned steel cables and hydraulic rams, enabling easy adjustment to a maximum depth of 2.5 meters. Open to the general public, it enjoys unlimited use by a variety of activity groups.

The leisure pool is a big draw for casual visitors. Landscaped with free-form boundaries and tropical vegetation, it consists of a large wading area with fountains and showering-water features as well as a water slide and flume ride leading to a small area where bathers can learn to swim. A group of spa pools allows bathers to relax and enjoy the pleasant surroundings.

Controlling Water Chemistry

In 1998, SIAC management chose to install five Strantrol[R] System 5 controllers to improve water quality. The units' High Resolution Redox[R] technology measures the actual oxidative effect of the addition of liquid chlorine (sodium hypochlorite) regardless of the pH, temperature, or bather load of the pool. When adding an oxidant for purposes of disinfection, the rate of disinfection is related to the millivolt redox potential in the water. A low millivolt reading indicates that more oxidant needs to be added.

A separate probe measures pH and initiates the feed of [CO.sub.2] gas to automatically correct pH. The water chemistry control system also displays free chlorine parts per million (ppm) as well as total alkalinity, calcium hardness, Langelier Saturation Index, and Ryznar Stability Index. These water balance calculations also enable the controller to make recommendations on overall improvements, which can be implemented to enhance the quality of pool water and bather comfort and extend equipment life.

Since installing the water chemistry control system, liquid-chlorine consumption at SIAC has been cut by 50 percent, to approximately 2,000 liters per week. This is a chemicals savings of almost 8400 each week. In addition, the system provides supervisory assistance and has noticeably improved water quality, which, in turn, protects bathers and the environment.

Other Benefits

As an additional safety precaution, the pools are superchlorinated once a week. This is accomplished automatically by programming the water chemistry control system. Dechlorination occurs quickly afterward by means of the pools' ozone (and chlorine) reduction granular-activated carbon filters.

An auto-probe wash feature, incorporated into the system, minimizes maintenance requirements by cleaning the probes on each controller nightly. To help minimize chlorine consumption, the controller automatically lowers chemical levels when the pools are not in use, and re-establishes the desired chlorine levels for bathers.

The water quality controllers are networked with voice and data modems on the facility's internal telephone system. The voice-modem feature allows controllers to provide a verbal readout of pool chemical levels, and enables security-protected adjustments to be made to controller settings using a phone keypad.

In the event of an alarm, the units can call as many as eight preprogrammed phone numbers for immediate operator assistance. This feature, which allows problems to be remedied before they become serious, protects swimmers and pool equipment and saves time and money.

The computer software, supplied with the water chemistry controllers by USFilter Stranco, enables SIAC management to log on to any of the controllers and monitor readings remotely; change settings, alarm ranges, and programmed events; and make other adjustments from a desktop PC.

Several weeks worth of data can also be downloaded, graphed, and added to the previous history for each pool. An easy-to-use inspection mode enables the graphs to be read with a simple pointer, which creates a digital readout of exact readings at exact times. Controller events, such as feeder activity, alarms, and individual operator adjustments, can also be recorded and presented on the computer screen.

In addition to providing assistance to operators who are fine-tuning chemical doses and feed rates, the software allows managers to better control operations at the Olympic facility by identifying any unnecessary or inappropriate adjustments being made to controller settings.

Overall, the advances in technology and chemical control have provided the Sydney International Aquatic Centre with a rapid return on investment and a dramatic improvement in pool management capabilities. With its state-of-the-art water chemistry control system, which provides consistent, high-quality swimming pool water, the SIAC is perhaps the first gold-medal winner of the 2000 Summer Games.

"These are exciting times for the aquatics world," says Terri M. Palmberg, CLP. "But our vision needs to grow and expand. Rather than focus on why it can't work, let's believe it can work in every experience we facilitate and provide."

Palmberg, a city of Mesa (Ariz.) Parks, Recreation and Cultural Division administrator and this month's guest editor, has assembled a collection of features that highlights the best of programming, facilities, and health and wellness in the aquatics arena. "The challenges of providing new aquatic experiences in the public and private sectors to meet leisure interests accelerate at an astounding pace," Palmberg continues. "The partnering, construction details, and staffing issues associated in today's fast-paced world leave us all shaking our heads and asking, `What's next?'"

How's the water Down Under? Couldn't be better, according to International Olympic Committee President Juan Antonio Samaranch, who dubbed the Sydney International Aquatic Centre, host to all aquatic events at the 2000 Summer Games in Sydney, Australia, "The best swimming pool I have seen in my life." Tim Batt, Asia Pacific region manager of USFilter's aquatic division, and Craig Dickson, a sales engineer with USF's chemical feed division in New South Wales, Australia, take a look at this truly spectacular aquatics facility (p. 54).