Water Plant Sampling Data
Total Hardness- the measurement of mineral content in water that is irreversible by boiling. Total hardness is determined by the multivalent cations' (Ca2+ and Mg2+) concentrations present in water.
Calcium Hardness- the measurement of calcium carbonate in mg/L.
Alkalinity- the measurement of our finished water's ability to neutralize acids and is the sum of hydroxide, carbonates, and bicarbonates. In Western Springs, our raw water comes from a limestone aquifer making our finished water more alkaline than most surface waters.
pH- the measurement of how acidic or basic the water is. Western Springs balances the acidity of the RO water by blending with raw water and treating with sodium hydroxide (NaOH) and a corrosion inhibitor prior to distribution.
Langlier Index- an approximate indicator of a solution's ability to dissolve or deposit calcium carbonate.
Free Chlorine- the chlorine that is still available in solution for disinfection.
Total Chlorine- Total chlorine is the sum of free chlorine and combined chlorine. Combined chlorine is the amount of chlorine used during the disinfection process and free chlorine is the amount of chlorine still available in solution for disinfection purposes, if needed. Total chlorine should always be greater than free chlorine.
Fluoride- An inorganic, anion of fluorine, its addition to water can be controversial; however, in Western Springs the fluoride is naturally occurring.
Iron- Naturally occurring in the aquifers that Western Springs pumps water from and is initially filtered out in pre-treatment.
TDS- stands for total dissolved solids and is a measurement of the amount of charged ions, including salts, minerals, and metals, that remain in solution.
Turbidity- the measurement of cloudiness or haziness in the water.
US EPA and IEPA Recommendations:
Fluoride: Current recommendation 0.7 mg/L (CDC, ADA, HHS, WHO)
Iron: Secondary IEPA limit is 0.3 mg/L, Primary IEPA limit is 1.0 mg/L
Hardness: 0-60/soft water, 61-120/moderately hard water, 121-180/hard water, >180/very hard water
TDS: Secondary IEPA limit is 500 mg/L
pH: Secondary IEPA limit is 6.5-8.5 su
Chlorine: 4.0 mg/L (as Cl2)