Utilities Water Treatment Process
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Water Treatment Facility

Wellington’s Water Treatment Facility (WTF) uses a dual treatment process for treating the Potable Water that its customers consume. Both Conventional Lime Softening and Reverse Osmosis (RO) are used to treat the Ground Water, which is supplied by 18 active wells; the wells are located around Wellington. Conventional Lime Softening is a common practice used to treat water in South Florida and Reverse Osmosis, which is a newer technology, is a mechanical sieving of the water.

Lime Softening is treated by adding the pretreatment chemicals of Quick Lime (CaO) and Polymer to an Upflow Clarifier. The Quick Lime raises the pH of the water to around 10.0. Raising the pH to 10.0 causes calcium carbonate to precipitates out of solution (calcium carbonate is essentially limestone). Because of the chemical reaction that takes place, the Calcium hardness is lowered to around 70 mg/L or 4.1 grains. Polymer acts as a weighting agent by physically attaching itself to the suspended solids in the water; once this attraction occurs, the particles and spent Lime sink to the bottom of the treatment unit, which is then pumped to a sludge solar lagoon. The lagoon is later cleaned out and used for agricultural purposes. Once the water leaves the Upflow Clarifier, it is then injected with Carbon Dioxide to lower the pH to around 9.0; Carbon Dioxide also aides in reducing the scale formation (the white spots that you may see on your vehicle after washing it) of water. After recarbonation of the water occurs, the water is then filtered through the multimedia filter bank that the WTF uses; the filters ensure the removal of any suspended solids that may not have been removed in the Upflow Clarifier unit. The filters are backwashed, approximately every 75 hours, to ensure efficient operation. The backwash water is captured in a holding pond and then retreated so that no water is wasted.

Once the water leaves the multimedia filters, it is then sent to either one of the two clearwells that are located on the plant site. Fluoride, Chlorine, Ammonia, and occasionally Caustic Soda are injected into the water for post treatment purposes. Fluoride is used to prevent tooth decay. The Village uses a combined Chlorine & Ammonia mixture to form Chloramines, which is used as a primary disinfectant. Occasionally the Village will temporarily convert to a Free Chlorine disinfection process, which will ensure a thorough disinfecting of the distribution system. This Free Chlorine run is performed, as a safety precaution, to ensure safe potable water is delivered to our customers. Caustic Soda is used for pH adjustment only when necessary. All of the chemicals that the WTF uses for pre and post treatment are NSF approved.

Exisiting RO Plant

The Reverse Osmosis (RO) treatment is a much different process; more sophisticated equipment and fewer chemicals are used to treat the water. Water is pumped from the well and injected with an Anti-Scalant solution to keep sparing soluble “salts” in solution so that the RO membranes won’t plug up. The water is then directed to any one of the 6 Cartridge Filter Housing, depending on which RO Trains are running; the Cartridge Filters remove particles down to about 5 microns (1 grain of Talcum power is about 50 microns). Once the water is filtered it is then sent to a High Pressure Pump, which pressurized the water to approximately 140 psi. The water is then sent to the RO membranes, which are housed inside multiple pressure vessels. The RO membranes reject constitutes based on their physical size, molecular weight, or by their natural charge. Generally, 75% of the water is recovered as Permeate (finished water) and 25% is rejected and sent into a Deep Injection Well (DIW) that is located on the plant site. The DIW is approximately 3200 feet deep and the reject water is blended with the lower Floridian Aquifer. The 75% of Permeate water that’s recovered is sent to a Degasifier system, which removes excessive Carbon Dioxide and Hydrogen Sulfide. Once the water leaves the Degasifier system, it is then sent to one of the two clearwells that are on the plant site where it is then blended with the Lime Softened Water. New RO Plant

Once the blending and chemical injections are completed, the water is then pumped to one of the four Ground Storage Tanks on the plant site. The Village has the ability to store 4.25 Million Gallons of Water onsite and an additional 4.0 Million Gallons of Potable Water offsite. Ground Storage Tanks are used to ensure that adequate amounts of water are available for peak flow times, which is usually from 4 am to 9 am and 5 pm to 9 pm. The Village’s WTF has backup emergency generators that can provide power for the entire plant operations in the event of a power outage or natural disaster.

The WTF is capable of treating approximately 12.0 Million Gallons per day of potable water. Finished water flows will vary each day depending on the time of year and weather conditions. The Village operates a full time lab and our water quality meets or beats the Maximum Contaminant Levels (MCL) set forth by the United States Environment Protection Agency (USEPA), the Florida Department of Environmental Protection (FDEP), and the Palm Beach County Health Department (PBCHD).

Should you have any questions regarding our water quality or treatment process, please feel free to contact us at (561) 791-4037.