Can You Trust Water From Urban Storm Drains?

Sources of Contamination

Urban storm drains collect rainwater and surface runoff from streets, sidewalks, and buildings. This water often carries pollutants such as bacteria, viruses, and chemicals from sewage overflows, animal waste, and industrial runoff. According to the US Environmental Protection Agency (EPA), stormwater can contain high levels of pathogens, heavy metals, and other pollutants that pose serious health risks.

Assessing Water Quality

Before considering water from urban storm drains for drinking or other uses, assess its quality by observing its appearance, smell, and taste. Clear water with no strong odors or tastes may still contain pollutants. Use a portable water testing kit or send a sample to a laboratory for analysis to determine the presence of pathogens, heavy metals, and other contaminants. These tests can detect E. coli, total coliform, and other bacteria that indicate potential waterborne pathogens.

Treatment and Purification

If you must use water from urban storm drains, prioritize water purification. Use a portable water filtration system or a water purification tablet that can remove bacteria, viruses, and other pathogens. Consider a system with a 0.2-micron filter or smaller to capture most contaminants. For example, the Sawyer Mini Water Filter can filter up to 100,000 gallons of water and remove 99.9% of bacteria, 99.99% of viruses, and 99.99% of contaminants. Always follow the manufacturer’s instructions for use and maintenance to ensure the effectiveness of your water purification system.