Hardness of Water

Asked January 5, 2016, 8:18 PM EST

I live in DC and would like to know how hard our water is? I'm having trouble with my dishes having a film left on them after the dishwasher and wonder if this is the issue. Thank you, Arleen

District of Columbia County District of Columbia

2 Responses

The MDE (Maryland Department of the Environment ) has a list of certified water testing labs. http://www.mde.state.md.us/programs/Water/Water_Supply/Documents/MD_Cert_Drink_Water_Lab_List.pdf
Home improvement stores, like Lowes or Home Depot, sell a DIY water testing strip for testing hard water.


Hard water can have that effect. Hard water is water that primarily has calcium and magnesium salts dissolved in it, mostly the carbonate salts. Other salts can contribute to the problems, too. The water hardness is a secondary water quality parameter because there are no adverse health effects. If you are on a private well, you are responsible for the testing of your water. Here is information on testing and interpretation of your own water.

Drinking water rules require that all public water systems provide a report of the quality of the water they produce. You can go directly to the water system website or office and request that report. EPA has a page where you may search for the contact information for your water supplier. If you are on DC Water or Washington Aqueduct you can find your water quality report here. If that is your water supplier, the report says the hardness averages 7.5 grains per gallon. that is considered hard water and can cause the symptoms you describe on your dishes.

Here is some information on home water treatment systems. If you are on a private well, home water treatment companies often test your water in hopes of selling you a treatment system. Research the water testing and treatment systems options to understand their slaes pitch. Buy only what you need.