The Center for Watershed Protection surveyed 750 residents, divided equally between Maryland, Pennsylvania and Virginia, on three easily modified behaviors that can influence water quality: lawn fertilization, cleaning up dog wastes, and septic system maintenance.
Dense urban areas, such as Washington and Baltimore, were not surveyed, because they lack of septic systems, have smaller or no yards, and surveys have shown that yards in urban areas have lower fertilization rates than those in suburban areas.
Almost everyone surveyed, 91 percent, maintained their own lawn; 7 percent used a lawn care company. Of those who maintained their own lawn, about two-thirds got no advice on lawn care management.
Half of those who maintain their own lawn said they did not use fertilizer. The survey found that those with higher levels of education and more income were more likely to use fertilizer.
Of those who fertilized their lawn, 48 percent said they fertilized once a year or less, and 83 percent fertilized twice a year or less. Seventy-three percent applied fertilizer in the spring. Typically, the Center’s report noted, homeowners are advised to fertilize their lawn only once a year, and to do so in the fall.
About half of those using fertilizer said they followed instructions on the container when applying it; the rest said they decided for themselves how much to use. Significantly, 84 percent of respondents had not received or performed a soil nutrient test in the past three years to determine whether they even needed fertilizer.
Most, 79 percent, said they did not apply pesticides to their lawn and garden. Of those who did, 55 percent said they followed directions on the product label.
About half of the residents surveyed had a septic system. Of those systems, 46 percent were more than 20 years old, which is the average design life for a septic system.
Almost 88 percent of residents knew where their septic system was located; those older than 45 were more likely to know the location than younger people.
The survey found that 50 percent had not had their septic systems inspected in the last three years, and 46 percent said their systems had not been cleaned in the last three years.
When asked about their awareness concerning septic system maintenance and water quality, 30 percent either disagreed or expressed no knowledge in regard to the statement, “Routine inspection and clean out of septic tanks is necessary to protect the water quality of the Bay.”
“The phone survey responses support the contention that there is a general lack of understanding of the maintenance required to ensure a proper functioning septic system,” the report said. “Most septic outreach materials recommend an annual inspection of the system to minimize maintenance costs and extend the life of the system.”
Nonetheless, most residents seemed knowledgeable about what was acceptable, and unacceptable (coffee grounds, grease, facial tissues, etc.) to go into a septic system.
Regarding dog wastes, 41 percent of Bay residents indicated they owned a dog, and of those, 56 percent personally walked their canine. A third said they rarely or never picked up after their dogs, or refused to answer the question. Nearly half of those “bad actors” indicated they were unlikely to change their habits.
Many dog walkers, 37 percent, did not agree, or expressed no knowledge, when asked whether they thought pet waste contributed to water pollution. Studies have shown that pet wastes not only contribute nutrients, but are also a major source of fecal coliform contamination in urban waterways. “Obviously, a stronger connection between pet waste and water quality needs to be established before nutrient education efforts can hope to change deeply rooted behaviors like refusing to clean up after one’s dog,” the report said.
Tom Schueler, director of the Center, cautioned that some results need to be taken with a “grain of salt.” Some people may not volunteer they are doing something harmful.
And, in some cases, people may not be knowledgeable enough to give the correct answer. For example, he said, pesticide application may be underreported because of the recent growth of “weed and feed” products that combine fertilizer and herbicides in the same package.
One Minnesota study found that 63 percent of residents reported using such products, but only 24 percent understood that they were applying herbicides to their lawn. Also, those who rely on professional lawn care services often do not know what is being applied.