| Level1 : | Non-abrasive - No bedload. |
| Level2 : | Low Abrasion - Minor bedloads of sand and gravel and velocities of 5 ft/sec. or less, or storm sewer applications. |
| Level3 : | Moderate Abrasion - Bedloads of sand and gravel with velocities between 5 and 15 ft/sec. |
| Level4 : | Severe Abrasion - Heavy bedloads of gravel and rock with velocities exceeding 15 ft/sec. |
There is a correlation between water softness and resistivity. A high resistivity level will be an indicator of a lower calcium carbonate concentration. Therefore, if a site has a resistivity ≥ 10,000 ohm-cm, this could be an indicator that soft water is present