Cities across America engage in numerous practices designed to keep pollutants out of waterways. Some solutions attempt to capture pollution before it drains into waterways. The captured water undergoes treatment before the cleaner water gets released.
These end-of-pipe, infrastructure-based solutions play key roles in preventing water pollution, but they also present cost-effectiveness issues. According to WorldSweeper.com, it costs 4 to 10 times more to treat already polluted stormwater than to perform street sweeping. Street sweeping picks up many dangerous contaminants before they get swept into stormwater runoff and natural bodies of water.
If your city engages in street sweeping, you want to make sure those efforts produce optimal results. Check out the best management practices for street sweeping below to find areas where your city can improve.
1. Perform Street Sweeping to Reduce Pollution, Not to Make Streets Look Good
Some cities send street sweepers out most frequently to downtown areas. These areas experience high amounts of traffic and represent the heart of the city, so sweeping their roads regularly allows the city to maintain a clean image for citizens and visitors.
However, sweeping mainly for aesthetic reasons misses the point. Downtown roadways tend not to have as many dangerous, pollution-causing particles as arterial roads. To reduce stormwater pollution in a cost-effective manner, city officials should set up a schedule that promotes pollution-focused street sweeping, not cosmetic street sweeping.
2. Target Arterial Roadways
Arterial roadways are the widest, busiest city roads because they funnel cars to and from major thoroughfares, like highways. These streets accumulate the most pollutants. For example, figures from Seattle show that arterial roads make up on 4% of the city’s surface area but contribute 16% of the pollutants in stormwater.
Targeting arterial roadways allows street sweepers to pick up the most contaminants while driving the fewest miles. This plan of attack uses stormwater pollution prevention funds effectively and keeps more pollutants out of the water.
3. Focus on Removing the Smallest Particles
The public tends to think about street sweeping as a means to clear away large debris on roadways, such as fall leaves and the aftermath of a parade or street festival. It’s important to clear away large debris, but the smallest particles on roadways ultimately cause the most problems in stormwater.
Which small particles are the worst offenders? The culprits include:
- Brake dust
- Auto exhaust remnants
- Zinc from car tires
Our cars shed these small particles and leave them on city streets. As soon as strong rain comes down, the pollutants get swept away into storm drains and towards natural waterways. Regular street sweeping on busy roads and sweeping performed before precipitation falls can reduce the contamination caused by these small pieces of debris.
4. Use Street Sweepers That Collect Data
Newer street sweeper models have the capability to collect data while they sweep. This information becomes invaluable to city planners who want to ensure their efforts make a difference and their funds are spent wisely.
- Data-collection computers in street sweepers may be able to track the following: Miles traveled
- Amount of trash and pollutants collected
- Fuel used traveling to and from landfills
- Routes of street sweepers
- Probable endpoint of runoff from each part of a route
If your sweepers collect this data, examine it closely so you can further refine your street sweeping routes and practices. Make sure you also analyze the trash and debris collected by your sweepers so you know the most common and most dangerous contaminants lining your city’s streets.
Use the best practices described above to streamline your city’s street sweeping efforts. Check out our other blogs posts for more insights into the benefits of street sweeping.