Where Does the Salt (NacCL) in my Well Water Come From

Salty potato chips are a treat, but excess salt in your well water is something that should be looked into. Salt can enter ground water and well systems from some sources, from sea foam to road salt. When salt dissolves in water, it breaks up into positively- and negatively-charged sodium and chloride ions. These ions are so common that they are found in every water supply at some level.

The most pristine water in New Hampshire has less than 20 milligrams per liter, or parts per million, of sodium and 30 mg/L of chloride. On the Seacoast, the sodium and chloride levels are often higher – about 75 mg/L of sodium and 150 mg/L of chloride. This is caused by the proximity to the ocean and the effects of wind-blown sea spray.

Higher sodium and chloride levels in other areas usually mean there is contamination from human activity, such as road salt, discharges from water softeners, animal or human waste disposal and contamination from a landfill.

Why more chloride?

As you can see in the data above, the amount of chloride found tends to be higher than the amount of sodium. Usually, the concentration of chloride is about 50 percent higher than the sodium concentration because of the difference in their atomic weights.

Are there any health risks having salt in my well water?

The Environmental Protection Agency and the Federal Safe Drinking Act do not list sodium and chloride on their list of hazardous contaminants, and there are no recommended levels for sodium and chloride in drinking water. In fact, the majority of sodium we ingest every day comes from food. That amount far outweighs what anyone would find in New Hampshire’s drinking water. To put it in perspective, milk has a sodium concentration of about 500 mg/L, more than six times the level found in water with elevated sodium levels.

Where do sodium and chloride come from?

A common source is from road salt, spread on roads, driveways, and stairwells to prevent slippery conditions during snow and ice storms. In the United State, an average of 23 million tons of salt was applied to roads, parking lots, sidewalks and driveways each year between 2005 to 2009. Studies have shown that in urban areas, about 95 percent of the chloride that enters local watersheds comes from road salt. This is especially a problem along the Interstate 93 corridor, where there are four impaired watersheds.

Another source of sodium and chloride is water softeners. During the water filtration process, water interacts with a salt resin. The contaminants, like calcium and magnesium, are replaced with sodium. As a result, sodium is added to the home’s drinking water, as well as the discharged water brine. The amount of sodium added is based on the water’s hardness level – the more hardness, the more sodium is needed to treat the water.

How do I prevent or reduce well water contamination?

The NHDES monitors road salt usage and its effect on local water bodies. On this fact sheet, you will find information about best practices you and your community should employ to keep the risk of sodium and calcium contamination down.

In home water softeners, the amount of water brine can be reduced by using a water meter or ion probe to trigger the resin regeneration cycle, therefore reducing the amount of sodium discharged into your septic system.

Do I need a whole house water filtration system?

If you are concerned about sodium in your water because of health issues, there are ways to treat your home water supply without adding more sodium. Skillings & Sons have experienced water system professionals who can advise you on your options.