Environmental Enemy #1 for Street Sweepers: Stormwater Runoff

Stormwater runoff is the biggest environmental issue plaguing the street sweeper industry. In an urban environment, roughly 55% of rainfall leaves impervious surface in the form of runoff. Due to the design of most stormwater collection systems, this runoff is flushed into our watersheds. Street cleaning has the greatest potential for reducing storm water pollution in the urban environment, and it can do so at a relatively affordable cost.

Joe Hendrickson, National Sales Manager for Schwarze Industries says, “That’s because half of all of the rain that falls on impervious surfaces goes onto pavement that is directly connected to an urban storm water collection system.” Luckily, sweepers that pick up even the finest particulate fractions have entered the market.

According to the National Education for Municipal Officials, basic steps to help reduce road runoff include:

• Avoid disturbing natural drainage patterns.
• Vary the pavement according to the proposed use, keeping narrower widths (with less runoff) in slow speed zones.
• Incorporate alternative stormwater management techniques such as vegetated swales.
• Mandate curb and gutter drainage with a minimum distance between catch basins.
• Assure minimum lot widths and side yards produce roads that are built for the minimum required pavement width needed to support projected traffic volumes.
• Minimize the number and width of cul-de-sac roads.
• Minimize turnaround radii on cul-de-sacs.
• Use permeable pavement surfaces where possible.

Street sweeping also helps to remove pollutants on the impervious surface, down to 2.5 microns. These pollutants consist of rubber particulates, engine soot, oil, & many more hazardous chemicals. It is the sweeper’s job to remove these from the roads and parking lots before these chemicals enter our ecosystems. And Schwarze has the right sweeper for the job.

The Regenerative Air street sweeper has proven to be the best product that Schwarze manufactures for eliminating the fine particulates from the surface. Hendrickson explains, “This is related to the design of the Regenerative Air sweeper recirculating the air within the system without a requirement to exhaust air back into the atmosphere. Our Regenerative Air Street sweepers also use a ‘blast orifice’ which forces pressurized air into the pavement, dislodging the fine particles from the cracks of the surface.”

Schwarze is also currently manufacturing CNG versions of the A7000, A8000, & A9000. As a cleaner alternative to diesel, and with infrastructure developing throughout the United States, Hendrickson says, “We look forward to the CNG product being a more common technology in the coming years.”

Another plus of street sweeping, since it picks up polluted material prior to its dilution into the runoff stream, is that it can remove soluble pollutants such as metals and nutrients that generally thwart structural BMPs. The Vacall AllSweep models, like Schwarze, are manufactured with maintaining the cleanest environment in mind.

Designed by Gradall Industries for high performance cleanup jobs, Vacall AllSweep models have a massive sweep system that’s wider than the width of the sweeper vehicle, enabling it to clear large amounts of debris quickly from highways, parking venues and runways. And that translates into a cleaner environment.

To further improve operating efficiency, AllSweep models are equipped with the new Vacall AllSmartFlow™ CAN bus control system that monitors machine performance on a colored LCD display screen. Maximizing operating efficiency, the control system allows for more precise water flow and vacuum adjustments using a fully proportional pendant, either wired or wireless to make productive control away from the chassis possible.

While other sweepers require two engines, the AllSweep uses just one. Using the chassis engine to also power the machine’s high performance centrifugal blower and vacuum can dramatically reduce pollution, fuel consumption and routine engine maintenance time and cost while also helping to control the overall cost of the machine.

When the sweeper is in use, a new hydrostatic drive system controls chassis travel speed while maintaining a specific RPM level to deliver consistent hydraulic power, water flow, vacuum forces and other cleanup functions—a revolutionary concept to assure excellent performance for multi-function equipment using a single engine.

Schwarze is also going beyond just building the best sweeper to help keep the environment clean. They are embarking on a big “Green” in the form of education. “It is our job as industry professionals to help inform the consumer about the environmental impact of polluted storm water runoff, and the value of street sweeping in the reduction of hazardous waste entering into our watersheds,” Hendrickson says. “It is our responsibility to ensure that the cleanest water possible is being transferred into these watersheds, therefore, preserving the natural habitats that help support our ecosystem.”

Story by Megan McClure