St. Lucie West has a new  stat e-of-the-art , high-technology water  plant. The St. Lucie West Service District's water plant began operating in 1988 as one of the largest low pressure reverse osmosis (RO) treatment plants in the US. Our new plant uses the same RO treatment. but we're now using raw water from the deeper Floridan Aquifer well.
To date. St. Lucie West's drinking water has come from shallow (surficial) aqui­ fers. Because of St. Lucie West's growth. we are beginning to overdraw the shal­

Where does the
15% go?

low aquifer. This is contributing to wetlands drying and lower lake levels. Three new Floridan Aquifer wells a re drilled to 1.300 feet below the ground-a much more plentiful source of raw drinking water for our community . Each well sup­ plies 1.400 gallons of water per minute or 2 million gallons per day.
In addition to being a more plentiful source of raw water. these new Floridan Aquifer wells are completely isolated from the shallow aquifer and will reduce the draw from the lakes in St. Lucie West by about 50% on a yearly basis. and almost entirely during the dry winter months.

Reverse Osmosis (RO) is the future of water treatment. The state-of-the -art RO process uses high pressure to force water through thin. semi­ permeable RO membranes. leaving unwanted
contaminants behind. RO treatment units recover about 85% of the water that is forced through the

The waste flow from the reverse osmosis (RO) process is basically concen­ trated well water. All con­ taminates removed from the potable  water during the RO process end up in the waste flow. commonly call ed concentrate or brine. This waste water has about 75% of the strength of sea water.
In Florida. there is a geo­ logical format ion about 1/2 mile below the surface that contains salt water instead

RO membranes

membranes. The other 15% washes away contam i­ nants filtered out during the process. such as salt

of freshwater. We inject our waste flow into this salty

and calcium. These membranes must be cleaned every six months with a mild
detergent to remove any silt.

The waste flow water (which is sim ilar to sea water) from the RO units is inject­ ed into the Boulder Zone using a specia l " inject ion" well.

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Our new RO system can treat up to 3.4 million gallons of water per day- that' s

formation for disposal. The several "confining" layers between the surface and the injection zone protect drinking water sources.

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Our new system will inject

equivalent to 225 1 5.000-gallon swi mming pools!

Creating perfect water. The RO process removes virtually all impurities from the water. leaving the water with no taste. The water is also very corrosive because of its purity and low  pH.  The new  plant uses calcite contactors to add hardness and make the

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about 15% of the raw water into the injection well-about 500.000 gal­ lons per day into this zone.

water less corrosive. The hardness also adds "taste" to the water. In these calcite contactors. the purified water flows up through a bed of calcium carbonate (ground marble) where the water dissolves the calci­

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um- adding the mineral back into the water- which creates a desired "hardness" and raises the p H .

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Calcite contactors

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ST LUCIE WEST
SfRVICfS, ii S'RICT

How are odors removed from the raw water?
Raw well water often has a "rotten egg" smell that

Raw water pumps

Millions of gallons, ready on demand. The treated water is stored in an enormous potable water storage tank at the water plant. Water from is stored in a 2 million gallon tank to satisfy the peaks and valleys of water demand throughout the day.

comes from its high lev­ els of natural sulfur . This sulfur is harmless. but it is removed for aesthetic purposes as part of the treatment process.
The water flows from the calcite contactors into large tanks called degassifi ers.
These degassifiers remove the hydrogen sulfide (sulfur) and excess carbon dioxide from the water.
The unwanted gasses are removed as the water cascades down through a loose media inside the
tanks and air is forced up through the water.

High service pumps deliver direct to your door. The pump room is one of the most imp ressive aspects of the plant expansio n. High-service pumps draw the clean water from the potable water storage tank and pump it out to your home or business. These four pumps can deliver 4,500 gallons per minute or
6.3 million gallons per day. They are designed to meet peak drinking water and fire service demand for St. Luc ie West.

Various chemicals ensure safe , healthy water. Many natural chemicals go into the treatment process. help ing to ensure your health and well-being. Acid is used to lower the pH for the reverse osmosis (RO) treatment. Causti c feed raises the pH after the RO treatment to stabilize the water. An anti- fou­ lant keeps the membranes clean and chlorine is the disi nf ectant that keeps the drinking water safe for use. In addition. we add fluoride into the water­ which is very important for children's growing teeth.

In an emergency, a generator keeps the plant up and running. The 1,800- horse power emergency generator sits just inside the pump room. This mam­ moth diesel-run machine can provide up to 1,350 KW of power- 100% of what is needed for both the new water plant and the existing wastewater operation.
Emergency generator