A pilot program to evaluate better methods to save water in drought-stricken California demonstrates that governments and businesses can save millions of gallons of water.
After 18 months of operation at LA City Hall East, a treatment system installed by Scottsdale, Arizona based Dynamic Water Technologies showed more than a 90 percent savings in chemical costs, and a water use reduction from 5.95 million gallons a year to 4.78 million, a savings of 1.17 million gallons or 20 percent less water.
After an extensive evaluation process, DWT was selected by the Department of Energy's High Impact Technology Catalyst Program, which evaluates emerging technologies that save energy and natural resources, to participate in the pilot program.
The Energy Department's National Renewable Energy Laboratory served as an independent monitor.
The NREL tracked the system's performance from April 2018 to October 2018.
NREL released the final numbers of the study in September 2019.
In comparison to other traditional and non-traditional methods used by the city, city leaders found the results were so conclusive that the Los Angeles City Department of Water and Power contracted with Dynamic Water Technologies to install the reactors at the city's downtown headquarters as part of the city's proactive efforts to save water.
NREL established pilot programs at a variety of facilities, including LA City Hall East.
The East Hall, named James K. Hahn City Hall East after former mayor James K. Hahn, is home to the HVAC plant that supplies cooled water to East City Hall and the adjacent city hall building.
It is 18-stories tall and contains about 530,000 square feet.
Cooling tall buildings uses an enormous amount of water that is circulated throughout the cooling system.
The water is used for several cycles, but has to be replenished or completely removed when hazardous contaminants and scale accumulate.
Adding water to replace water lost to evaporation and the cooling process is called "make-up" water.
The dirty, contaminated water that is removed is called "blowdown" water.
In the LA City Hall study, NREL reported a 19 percent reduction in make-up water and a nearly 66 percent decrease in blowdown.
Before the DWT installation, water was recycled between 3-5 times.
After the installation, water cycles exceeded 10 cycles.
In addition, the DWT system reduces mineral build-up in tubing, pipes and throughout the cooling system, extending the life of the equipment, and again reducing costs, he said. ■