By Lynne Richard, Portland Water District
One of the most serious threats to clean water is pollution carried by spring’s snowmelt runoff, especially that known as the “first flush.”
It’s a special problem, unique to cold climates: months and months of snow accumulates in snow banks- holding on to whatever is deposited with it. By winter’s end, those nasty brown snow banks hold a season’s worth of sand, salt, debris, pet waste, chemicals, metals, vehicle fluids: any substance that lands where snow is plowed or shoveled.
Water pollution occurs when the sun and spring showers finally melt the snow. Impervious surfaces like driveways, sidewalks, and streets prevent snowmelt and stormwater runoff from slowly percolating into the ground. Instead, dirty meltwater will sheet across paved areas toward nearby lakes, streams, rivers or wetlands.
Luckily, everyone can contribute to improving the quality of the melt water before it hits the lakes. There are a few simple habits that each of us can adopt to reduce the potential for spring pollution of our water bodies:
Keep the storm drains clear.
Avoid covering storm drains with leaves, brush or yard waste that will add excess nutrients to the discharge waters. Do not connect your floor drains or sump pump outflow to the storm drain; rather allow that water to percolate into your yard. Sweep up road salt and sand periodically to keep the drains from becoming clogged. And, don’t litter- even cigarette butts discarded outdoors can wash into the storm drains and pollute waterways. Sweep sand up before spring snowmelt, and do not sweep sand into stormdrains.
Flush or trash after you scoop.
Pet waste is a big problem! According to a 1999 Vanderbilt University study, dog feces are a major cause of water pollution in urban and suburban areas. The EPA estimated that in a small watershed, two to three days of droppings from a population of about 100 dogs would contribute enough bacteria and nutrients to temporarily close a bay to swimming and shellfishing. Toss that pet waste into the toilet or trash, where it can’t cause water pollution.
Use care with engine fluids.
A drop of oil the size of a quarter is enough to kill a seabird. Stormwater from one square mile of roads and parking lots can yield approximately 20,000 gallons of residual oil per year. If you have an accidental spill, absorb it with kitty litter and then sweep it up and take it to a disposal facility. Of course, never dump anything into a storm drain; take your used oil to a proper disposal or recycling facility.
Pump out your septic tank regularly. Effluent from poorly maintained or failing septic systems can rise to the surface and contaminate stormwater. Septic systems can be important sources of pathogens and nutrients, especially nitrogen, that are not effectively removed from the waste stream. One study found that 74 percent of the nitrogen entering the Buttermilk Bay estuary in Massachusetts originated from septic systems. Fecal coliform and other pathogens can be added to stormwater from improperly sited, designed, installed, or maintained septic systems.
Most of these spring practices are simply a matter of common sense, and good environmental hygiene.
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