Rain can be just as detrimental as it is beneficial. When rain cannot be taken up by soil and vegetation and begins running off of things like concrete, roofs, and hard surfaces it is then deemed stormwater. Stormwater can begin to pick up contaminants as it flows across these hard surfaces such as debris, oils, chemical contaminants like pesticides and fertilizers, and pathogens that can cause disease. Stormwater is conveyed to larger, more major receiving bodies of water, and the potential contaminants it can pick up along the way can lead to significant negative impacts. Because stormwater often reaches receiving waters untreated, it is imperative that every measure is taken to mitigate potential contamination.
Many stormwater contaminants are caused by day-to-day activities and can be easily prevented. Major contributors of chemical contamination are pesticides and fertilizers that are applied to lawns and neighborhoods every day. Pesticides can contain compounds that are toxic to humans and can cause harmful health effects. Some pesticides also contain compounds that are known carcinogens which pose additional risk to humans. When introduced to water, fertilizers can deplete the oxygen content of the water leading to further environmental degradation. When applying pesticides and fertilizers, be mindful of when and where you are applying them. Try to apply these substances during dry periods and when winds are minimal and as far away from bodies of water and storm drain inlets as possible.
Every-day maintenance and upkeep on vehicles and lawns can also contribute to stormwater impairment. Oil spills from leaking cars and oil changes can remain on impervious surfaces indefinitely until it is picked up by stormwater runoff. A small amount of oil can affect a large amount of water and is especially harmful to aquatic animals. Mowed grass can contribute to physical and chemical contamination of stormwater and receiving waters. Grass can carry pesticides and fertilizers with it when it flows into storm drains. It is also a physical contaminant since it can build up in storm drains causing water to back up.
Pathogens are another major source of contamination and a significant health concern. When stormwater rushes over parking lots and driveways, it can pick up fecal matter containing harmful pathogens. E. coli., Shigella species, and Vibrio species are just a few of the major disease-causing organisms contained within stormwater and can cause severe illnesses including diarrhea, cholera, typhoid, etc. Leaking or malfunctioning septic systems can contribute large amounts of these organisms to our waterways if left unfixed. Dumping of sewage and other hazardous waste commonly discharges directly into ponds, streams, rivers and drainage systems thereby directly contributing to physical and bacteriological contamination of waterways.
Contaminated stormwater is a serious issue facing communities and if we do not actively take steps to mitigate stormwater impairment, the results can be severe. Bacteriological contamination by fecal matter, chemical contamination caused by pesticide and fertilizer use, and the presence of oil and physical contaminants like cut grass are all major contributors to stormwater impairment. If these issues are not addressed, major receiving waters can become contaminated leading to drastic results. Be mindful of where debris and spills are ending up and exercise caution when using harmful chemicals.
We all play an invaluable role in ensuring stormwater remains unpolluted and we must continue taking steps towards keeping our waters as clean as they can be. To learn more, visit our website at www.vcphd.org.
Bryce Keith is the Stormwater Inspector for Environmental Services at the Victoria County Public Health Department. He holds a Bachelor’s Degree in Biology with a minor in Chemistry from Texas Tech University and certified by TCEQ as a Designated Representative.
