What Does It Mean if My Well Water is Corrosive Corrosivity Testing

After spotting the blue-green stains near your bathtub drain, you asked your friends and did some Internet searching to find the cause. You probably know by now that your water is likely corrosive, but you wonder what that means to your health and your home plumbing system.

What Is Corrosive Water?

Corrosive water is a condition caused by low water pH. When water’s pH level is low, it causes metals to dissolve from the metallic plumbing it flows through, especially when the water is hotter. Much of the water in New Hampshire, including both surface water and groundwater, is corrosive, so testing your home water pH level is recommended, even if you don’t see blue-green stains.


Corrosive water is not considered harmful itself, and there are many foods we eat, such as vinegar and orange juice, that are more corrosive than “corrosive water.” That blue-green stain you saw on your porcelain sinks and tub are the result of copper rust from the copper plumbing dissolving into your home’s water. Copper in small doses is not a major health concern, however in higher doses over time it can cause liver and kidney damage.

Sometimes corrosive water can dissolve lead from pipe fittings and seals. This condition is hard to detect because lead is colorless, odorless and tasteless. However, lead can be harmful to your health, especially in children. You should consider lead contamination a possibility if your home was built before 1980.

You can do a few things to avoid health risks, such as never cooking with warm or hot water, as they are likely to contain more metals. You can also flush your pipes by letting the water run for less than a minute. The New Hampshire Department of Environmental Services has calculated a formula you can use to determine how long you should flush your pipes before reaching fresh water. If you live in a tall apartment building or a housing development with shared plumbing, flushing may not be an option.


Corrosivity causes physical damage to piping, which will require you to replace your plumbing sooner than you would have to with non-corrosive water. Flushing the pipes before each use will lessen the metallic taste, but it won’t prevent damage to your pipes. Copper also gives water a metallic taste which can be unpleasant and in some cases can stain clothing and hair.


There are some methods to reduce the corrosivity of your home water supply that range from low-tech and inexpensive to costly.

Adding calcite chips to the bottom of an existing dug well can reduce corrosivity at a low cost, but can also cause hardness and alter the water’s taste. A more high-tech approach is diluting a solution of soda ash or baking soda into the water using a chemical feed pump. This does not increase the hardness of your home water supply, and the solution can be customized to treat your water depending on its pH level. It could, however, cause damage to some mechanical appliances in your home, and requires routine inspections and filling of the chemical solution every few weeks.

If you chose to treat your corrosive water, speak with a Skillings & Sons, Inc., technician for the best option for your home.