What, Why, How — Water Treatment Plants

Did you know that 99.7% of Earth’s water supply is not usable by humans? This unusable supply includes not only saltwater but fresh water supplies from lakes and streams that often contain waterborne germs such as Cryptosporidium, E. coli, Hepatitis A, and Giardia intestinalis. The water we drink, from taps and bottles and fountains, goes through an extensive treatment process to rid itself of these harmful pathogens.

A water treatment plant serves its local community by sourcing its water from the surface, from lakes, streams, reservoirs, or from the ground, where water pools after seeping in from rain or snowfall. The plant is then tasked with disinfecting and purifying this “raw,” or untreated, water. Below is a step-by-step look into how your water is treated:

  1. The first step of the purification process is coagulation and flocculation: in this step, a coagulant, such as aluminum sulphate or iron salt, is added to the water to neutralize the negative charge of any dirt, parasite, or bacteria that might be present. This neutralization enlarges the harmful particles in preparation for the following step.
  2. The second step is referred to as sedimentation, where the now enlarged dirt particles can more easily sink to the bottom of the water.
  3. The third step is filtration, where the water is run through sand, gravel, or charcoal to weed out the enlarged dirt particles.
  4. The fourth step is disinfection where a chemical such as chlorine or chloramine is added to the water to both kill any remaining parasites or bacteria and prevent the growth of new ones.
  5. Finally, the purified water is stored in a water tower and, with plenty of gravity and pumps, is delivered into your home.

Want to find out more about the quality of your drinking water? Visit this site to access an annual drinking water quality report from your local water supplier.


Trout Brook Project

KC, on behalf of the Village of Woodbury and the WP3 Subdivision Project, designed modifications to the Trout Brook Water Supply and Treatment facility located on New York Route 32 in the Village of Woodbury.

The Trout Brook Water Treatment Plant is integrated into the Town of Woodbury’s Consolidated Water District, which serves the residential development known as WP3.

The water system was originally designed to provide only disinfection via chlorination. Subsequent laboratory testing results of the wells indicated that TW-02 and TW-04 were ground water sources under the direct influence of surface water (GWUDI).

KC designed a filtration and ultraviolet (UV) treatment system to treat the water produced at this facility.

The filtration system consists of a series of two municipal high-pressure filter housing units, each with an allowable flow rate of 500 GPM sized to handle the combined discharge rate of all three wells.

The first filter housing unit, a Harmsco Model No. MUNI-5-4FL-304 HP, utilized five nominally rated 5-micron filter cartridges, while a second Harmsco housing unit contained five 1-micron absolute filter cartridges.

After the filters, an Aquionics UV Technology InLine+D 450 treatment system was installed. The system consists of one UV unit capable of operating at a flow rate of 364 GPM, while providing a minimum 40 mJ/cm2 dosage with a minimum UVT of 94%.

The additional filtration and UV treatment will ensure safe drinking water for all Village residents.