HOW TO INTERPRET A WATER ANALYSIS REPORT
AGRICULTURAL ENGINEERING FACT SHEET
The Pennsylvania State University College of Agriculture
Cooperative Extension Service, University Park, Pennsylvania
| Item | Normal Range | Average | Recommended
Maximum |
Effect of concentrations above acceptable limit |
| Lead | 0.0 0.005 | 0.005 | 0.015 | From solder or lead pipes, can cause impairment to mental development, especially in children. |
| Nitrates | 0.0 0.10 | 0.0 | 10 | Can cause "Blue Baby Syndrome" |
| Alkalinity (CO3, HCO3) |
14 286 | 150 | ------ | Measure of waters capability to neutralize a strong acid. High alkalinity (pH 8.0+) may have "soda" taste and drying effect on the skin. |
| Chloride (Cl) |
1 138 | 13 | 250 ppm | Sources of chlorides are from soluble salts such as sodium chloride (table salt). Brackish or briny taste and water is usually corrosive. |
| Iron (Fe) |
0.05 2.0 | 1 | 0.3 ppm | Most private wells have higher levels of iron than EPA max. recommended amount. Metallic taste to water: yellowish red stains on everything it contacts. |
| Manganese | 0.0001 0.05 | 0.05 | 0.05 ppm | Similar to iron: leaves black specks on bathroom fixtures |
| Sulfate (SO4) |
1 50 | 17 | 250 ppm | High concentrations could cause a cathartic (laxative) effect. Produces medicinal taste and may have a laxative effect on those not accustomed to it. |
| Total Dissolved Solids | 30 600 | 230 | ------ | The measurement of weight of all dissolved material in the water after evaporation. May settle out and build up scale in pipeline and water heaters. |
| Total Hardness (Ca and Mg) |
1 350 | 120 | ------ | Measurement of Divalent cations, magnesium and iron all expressed as calcium carbonate. Wastes soap, cleans poorly, causes lime scale. |
| pH Value | 6.3 8.5 | 7.8 | 6.0 8.0 | The amount of acid in water. 7.0 is neutral; pH values below 6.5 may results in corrosive water. PH values above 7.5 usually indicate hard water. |
| Calcium | 2 410 | 37 | 250 | Major contributor to hardness. Required by the body at 1000 mg/day. |
| Conductivity | 50 900 | 350 | ------ | A measurement of all dissolved solids in solution, this is a quick way to estimate the total dissolved solids. |
| Potassium | 0.3 65 | 2.5 | ------ | Does not contribute to hardness but high levels can impart salty taste. |
| Magnesium | 0.02 20 | 8.3 | ------ | The major cations in brine waters associated with gas drilling. Can cause the same types of problems in water as iron. |
| Sodium | 0.5 135 | 30 | 20 | Used in water softeners to regenerate resin. Is added to water at twice amount of calcium when water is softened. |
| Oil and Grease | ------ | ------ | <1 | Measurement of weight of all substances that are soluble in a particular solvent. Drinking water should be free (<1 mg/L) of oil and grease. |
| Barium | 0.005 0.10 | 0.05 | 2.0 | Barium is not a common contaminant of ground water. Levels above the EPA maximum may cause increased blood pressure and nerve damage. |
| Methane / Ethane | ------ | ------ | <0.066 | A result of 0.1 1.066 mg/L indicates that immediate hazard is not present but water "settle" before use. Meth/Eth will "bubble-out" in a few minutes. |
| Coliform | ------ | ------ | 0 | Group of bacteria that should NOT be present in potable water. If present, indicates contamination by surface or septic water. |
Results listed above are in milligrams per liter (mg/L).
Hardness classification
Classification Hardness (mg/L or ppm) Hardness (gpg)
Soft Less than 17 Less than 1.0
Slightly hard 17 to 60 1.0 to 3.5
Moderately hard 60 to 120 3.5 to 7.0
Hard 120 to 180 7.0 to 10.5
Very hard More than 180 More than 10.5
**Conversion formula
1 gpg = 17.1 ppm or gpg = ppm / 17.1
From an Agricultural Engineering Fact Sheet issued by the Pennsylvania State University, College of Agriculture, Cooperative Extension Service, University Park, Pennsylvania. Written by N. Henry Wooding, Extension Agricultural Engineer.