Despite the most advanced sanitation and purification equipment, some seemingly harmless everyday practices can contaminate our water supply. Here’s how to be more careful:

1. Avoid using chemical pesticides and fertilizers on your lawn and garden; if you do use them, apply sparingly. Runoff containing these chemicals can end up in nearby lakes, streams, and drinking water.

2. Use porous materials (such as wood, brick, or gravel) for decks, patios, and walkways. Unlike concrete, these materials allow rain to soak into the ground, reducing runoff. Place sand, gravel, or grass between paving stones instead of cement.
3. Seek natural alternatives to cleaning products that contain toxic and/or petroleum-based chemicals. Because many products marketed as “green” are not, review the ingredient list and look for possible certification by an independent organization.
4. Dispose of toxic waste properly. For example:
–Never dump motor oil, anti-freeze, paint thinners, or other chemicals on the ground, into sewers, or down the drain.
–Use mercury-free or rechargeable batteries.
–Never pour unused medicines down the sink or toilet.
5. States differ in their waste disposal requirements; California, for example, bans all alkaline batteries from household waste. For a list of accepted items, contact your local public works or waste management agency.
6. If you own a septic system, maintain it properly—septic system failures are a major source of groundwater pollution (and can cause waterborne illnesses).
7. Whenever possible, choose organic foods (which are grown without chemical fertilizers and pesticides) and meat and dairy products from pasture-based systems (which generate less air and water pollution than crowded CAFOs, or confined animal feeding operations, that confine livestock and concentrate their waste in small spaces).
8. Because the extraction and burning of fossil fuels such as coal, oil, and natural gas contributes to water contamination and acid rain, consider ways to reduce your use of these resources. For example, upgrade old appliances to more efficient models, or ask your utility about “green power” programs that allow you to obtain part or all of your electricity from renewable resources such as wind and solar energy.
9. Shovel your driveway as soon as possible after a snowstorm to avoid ice buildup and reduce the need for ice-melting products, which can contaminate water supplies and harm plants and animals. When you need extra traction, apply sand.

It’s worth noting that the Environmental Protection Agency (EPA) requires public water suppliers to provide customers with a yearly water quality report. If you’re among the 15 million U.S. households with a well, which the EPA doesn’t regulate, hire someone to regularly evaluate your water. And if you have small children and plumbing installed before 1986, you should test your water (regardless of its source) for lead, which can leach from old pipes into tap water and cause neurological problems.