Residential Stewardship
Residential stormwater stewardship involves the collective actions and everyday behaviors of residents to prevent pollution from entering local waterways. While individual household activities may seem small, their cumulative impact across a watershed is significant. Common residential sources contribute substantial amounts of pollutants to stormwater runoff, including nutrients from fertilizers, bacteria from pet waste, metals and hydrocarbons from vehicle maintenance, and sediment from yard erosion. When rain falls on residential areas, it washes these pollutants from lawns, driveways, and rooftops into the storm drain system.
Unlike wastewater, which goes to a treatment plant, stormwater and the pollutants it carries are typically discharged directly into the nearest stream, river, or lake without any treatment. This polluted runoff degrades water quality, harms aquatic life, and can make water bodies unsafe for recreational use. Promoting residential stewardship is a key component of a comprehensive pollution prevention program. By encouraging simple changes in household habits and property management, municipalities can effectively reduce pollutant loads at the source, protecting local water resources and improving community environmental health.
How the residential stormwater stewardship pollution pathway works
In developed residential areas, a significant portion of the landscape is covered by impervious surfaces like roofs, driveways, patios, and compacted lawns. When it rains, water cannot soak into the ground as it would in a natural, forested environment. Instead, it becomes stormwater runoff, flowing rapidly over these surfaces. As it travels, the runoff acts like a solvent and a conveyor, picking up and carrying pollutants left behind from daily activities.
A freshly fertilized lawn can contribute excess nitrogen and phosphorus. A car leaking oil on a driveway adds hydrocarbons and heavy metals. Pet waste left on the grass contributes bacteria and nutrients. These pollutants are then transported directly into the storm drain system, a network of pipes and culverts designed to prevent flooding by quickly moving water away from developed areas. This system serves as a direct conduit to local water bodies. The result is that common household activities become nonpoint source pollution, where contaminants from a broad area are consolidated and discharged into a single, sensitive receiving water.
| Activity / Source | Key Pollutants | Primary Pathway |
|---|---|---|
| Lawn & Garden Fertilization | Nutrients (Nitrogen, Phosphorus) | Runoff from lawns carries excess fertilizer into storm drains. |
| Pet Waste | Bacteria (E. coli), Nutrients | Waste left on the ground washes into storm drains during rain events. |
| Vehicle Washing | Detergents (Phosphates, Surfactants), Metals, Oil & Grease | Wash water flows from driveways directly into the storm sewer. |
| Automobile Fluids | Hydrocarbons, Heavy Metals (Zinc, Copper, Lead), Antifreeze | Leaks and drips on impervious surfaces are washed away by rain. |
| Failing Septic Systems | Bacteria, Viruses, Nutrients | Untreated wastewater surfaces and flows into ditches or groundwater. |
| Yard Debris | Organic Matter, Nutrients | Leaves and grass clippings clog drains and release nutrients as they decay. |
| Winter Salt Application | Chloride, Sediment | Melted snow and ice carry salt and sand into the storm drain system. |
Recommended practices
Adopting better household practices is the most effective way to reduce residential stormwater pollution. These recommendations focus on preventing pollutants at the source and managing rainwater where it falls.
Lawn and garden care
Proper landscaping and lawn care can significantly reduce nutrient and pesticide runoff.
- Test the soil before applying fertilizers to determine the specific nutrients needed. Avoid application before heavy rain is forecast.
- Use slow-release nitrogen fertilizers and low-phosphorus or phosphorus-free formulas.
- Keep fertilizer and pesticides off of paved surfaces by sweeping them back onto the lawn.
- Mow lawns to a height of 3 inches or more to encourage deeper roots and reduce the need for watering and herbicides. Leave grass clippings on the lawn (“grasscycling”) to return nutrients to the soil.
- Incorporate native plants into landscaping, as they are adapted to the local climate and require less water, fertilizer, and pest control.
Vehicle maintenance and washing
Cars and other vehicles are a major source of urban pollutants.
- Wash vehicles on a lawn or other unpaved surface where the water can soak into the ground, or use a commercial car wash where water is recycled and treated. See the dedicated page on car washing for more details.
- Regularly check for and repair fluid leaks. Use a drip pan to catch leaks until repairs can be made.
- Recycle used motor oil and antifreeze at an authorized collection center. One gallon of used oil can contaminate one million gallons of drinking water.
- Clean up spills immediately using absorbent material like cat litter, and dispose of it in the trash.
Pet waste management
Animal waste is a significant source of bacteria and nutrients in urban streams.
- Always pick up pet waste from yards, parks, and sidewalks.
- Seal the waste in a bag and dispose of it in the trash.
- Do not place pet waste in compost piles, as home composting temperatures are not high enough to kill harmful pathogens.
Onsite wastewater systems
Properly functioning septic systems treat wastewater before it reaches groundwater or surface water.
- Practice regular septic system care, including having the tank pumped every 3 to 5 years.
- Avoid disposing of chemicals, grease, or non-biodegradable items down the drain, as they can harm the system’s biological function.
- Know the location of the drainfield and avoid driving or planting trees over it to prevent damage.
Rainwater management
Managing rainwater on-site reduces the volume of runoff entering the storm drain system.
- Install rain barrels at downspouts to capture rooftop runoff for later use in watering gardens. A typical 55-gallon rain barrel can save over 1,000 gallons of water during a summer season.
- Direct downspouts away from paved surfaces and onto lawn or garden areas where the water can infiltrate.
- Consider installing a rain garden, a shallow depression with amended soils and native plants designed to capture and treat stormwater runoff.
Building a municipal program
A successful residential stewardship program relies on targeted education and outreach. The goal is to move beyond general awareness to achieve measurable behavior change. A first step is often conducting community surveys or focus groups to identify the most common polluting behaviors and the barriers to adopting better practices.
Outreach materials should be clear, specific, and action-oriented. Effective channels include direct mail, utility bill inserts, social media campaigns, and workshops. Partnerships with local garden clubs, watershed groups, and retailers can amplify the message. Some programs use community-based social marketing, which involves securing public commitments (e.g., signing a pledge to pick up pet waste) and providing prompts (like storm drain stencils or decals) to remind residents of their commitment.
Incentive programs can also be effective. Offering rebates for rain barrels, providing free soil testing kits, or sponsoring “build your own rain barrel” workshops can encourage adoption of specific practices. Neighborhood-level programs, where a group of neighbors works together to install rain gardens or adopt other practices, can create social momentum and increase participation. Tracking metrics like workshop attendance, rebate redemptions, and survey responses helps gauge program effectiveness and refine future efforts.
Behavior change campaigns are most effective when they focus on one or two specific actions at a time. A campaign targeting dog owners with the message “Scoop the poop, bag it, and trash it” is more likely to succeed than a general “prevent water pollution” message. Providing the necessary tools, like pet waste bag dispensers in public parks, removes a key barrier and further increases the likelihood of adoption.
Effectiveness
The effectiveness of residential stewardship programs is typically measured by behavior change metrics rather than direct water quality improvements, which are difficult to isolate and attribute to a single program. Success is often quantified by the number of residents who adopt a recommended practice. For example, a municipality might track the number of rain barrel rebates issued, the pounds of hazardous waste collected at drop-off events, or the percentage of residents who correctly answer survey questions about proper fertilizer application after an outreach campaign.
While isolating the exact pollutant load reduction from these diffuse activities is challenging, the cumulative potential is significant. Widespread adoption of practices like downspout disconnection or reduced fertilizer use can lower runoff volumes and nutrient loads across a watershed. Municipal managers can use tools like the Simple Method runoff calculator to estimate potential load reductions from changes in land cover or impervious surface connectivity. Studies have shown that targeted, persistent outreach campaigns can result in adoption rates of 10-30% for certain behaviors, leading to meaningful, long-term improvements in local water quality.
Frequently Asked Questions
How can one person’s actions really make a difference for water quality?
While a single action may seem small, the combined effect of thousands of households in a watershed is enormous. Residential areas are a primary source of nonpoint source pollution. When a significant portion of residents adopts practices like proper fertilizer use, picking up pet waste, and preventing oil leaks, the cumulative reduction in pollutants like nutrients, bacteria, and hydrocarbons can lead to measurable improvements in the health of local streams and lakes.
What is the most important first step for a resident to take?
A great first step is to manage the water that falls on the property. Directing downspouts from paved surfaces onto lawn or garden areas is a simple, no-cost action that reduces the amount of runoff entering the storm drain system. This allows rainwater to soak into the ground, filtering out pollutants naturally. Another high-impact action is to always pick up pet waste, as it is a direct source of harmful bacteria in local waterways.
Are “flushable” wipes and other products safe for septic systems?
No. Most products marketed as “flushable,” including wipes, cat litter, and paper towels, do not break down in septic systems. They can clog pipes, accumulate in the septic tank, and lead to system backups and premature failure. The only things that should be flushed down a toilet connected to a septic system are human waste and toilet paper. Everything else, including grease, chemicals, and pharmaceuticals, should be disposed of properly in the trash or at a hazardous waste facility.
How much does a rain barrel cost and where can I get one?
The cost of a rain barrel typically ranges from $70 to $150, depending on its size, style, and features. Many local governments, conservation districts, or watershed groups offer subsidized rain barrels or hold workshops where residents can build their own at a reduced cost. Hardware stores and garden centers also carry a variety of models. Before installing one, check local ordinances, as some municipalities may have specific requirements for installation or overflow management.
Why is washing a car on the lawn better than on the driveway?
When a car is washed on a driveway, the soap, dirt, oil, and grime are washed directly into the storm drain, which leads to the nearest stream. The soil and grass of a lawn, however, act as a natural filter. The wash water soaks into the ground, where soil microbes can break down the detergents and trap pollutants like metals and hydrocarbons. This prevents them from reaching local waterways. Using a biodegradable, phosphorus-free soap further minimizes the environmental impact.
What is the best way for a municipality to start a residential outreach program?
A good starting point is to identify the one or two most significant residential pollution sources in the community. This can be done by reviewing water quality data or conducting a simple “windshield survey” of neighborhoods to observe common behaviors. Next, conduct a small community survey to understand residents’ current knowledge and perceived barriers to change. Use this information to design a targeted campaign with a clear, simple message and a specific call to action. Starting small and focused allows the program to build momentum and demonstrate success.
How often should a septic tank be pumped?
As a general rule, most septic tanks require pumping every three to five years. The exact frequency depends on the size of the tank, the number of people in the household, and the volume of wastewater generated. Some systems with electrical float switches, pumps, or mechanical components may need more frequent inspections. Regular pumping and inspection by a licensed professional is the most important maintenance activity to prevent system failures, which can be costly to repair and can release untreated sewage into the environment.