Two common best management practices (BMPs) that municipalities can use to manage nonpoint-source pollutants under a National Pollutant Discharge Elimination System (NDPES) stormwater permit are street sweeping and catch basin cleaning. Stormwater managers have plenty of equipment options available for these tasks.
Street sweeping equipment, in particular, has seen an evolution in recent years. Johnston North America points out that street sweeping is a nonstructural source control. These types of controls prevent pollutants from entering stormwater flows through the expansion of cleanup programs, such as street sweeping, sidewalk sweeping, cleaning of storm drains, and enforcement actions against illicit dischargers.
EPA and the states have recently focused on small debris particles (PM10, or particles with a diameter of 10 microns or less) because heavy metals and other pollutants have been shown to attach to them. These particles become total suspended solids during rainfall and fugitive dust that gets blown around in dry weather. As a result of this emphasis, manufacturers are attempting to facilitate the effective removal of these fines.
Recent efforts to better deal with the tricky challenge of keeping the finest dust out of stormwater have resulted in more than one type of street sweeper. Stormwater managers can choose from among mechanical broom sweepers, vacuum sweepers, regenerative air sweepers, and new dry sweepers.
Mechanical broom sweepers typically are equipped with a main broom that moves side to side. Many also have gutter brooms on one or both sides of the machine. Typically, they are also equipped with a conveyor system and collection hopper.
Vacuum sweepers have an engine that powers a fan to generate a vacuum. On many models, the sweeping head has an intake for dust and debris. These machines exhaust the air that was used to pull up debris.
Regenerative air systems were designed with the idea of picking up PM10 effectively, cleaning a wider path, and minimizing the return of dust into the atmosphere. These machines have a vacuum inlet on one side of the sweeping head and continually recirculate their air supply internally by blasting the air into the sweeping head on the side opposite the inlet. As the sweeping head moves across the pavement, the air is blasted down onto the pavement on one side of the head and travels across the width of the head, gathering debris in the process. The swirling air is carried up the pickup hose on the other side with the debris. Besides PM10, these machines also pick up larger, light material such as leaves, as well as heavier construction debris. They use water for dust suppression.
In recent years, a fourth class of street sweepers has emerged. Dry sweepers work without using water and have robust filtration systems for dust containment. An example of a dry sweeper is Schwarze Industries’ EV-series machines. These units clean pavement across the full width of the sweeping head and are equipped with a self-cleaning filtration system that filters dust output down to 2.5 microns.
Below is a list of pavement sweeping and catch basin cleaning machines.
Federal Signal (Elgin Sweeper, Vactor Manufacturing)
The Megawind combination leaf and debris vacuum and catch basin cleaner from Elgin Sweeper features an optional street sweeper system. The large 12-inch leaf and debris hose system features an articulated power boom with 180-degree rotation supported by a high-performance vacuum system and large-capacity debris body.
The machine is engineered for pickup and flexibility to handle debris from compacted dirt, gravel, sand and bulky debris to leaves and other smaller particles found in the street and in catch basins. The unit is available on a conventional chassis or a premium Nissan Diesel UD3300 chassis, with right-hand steering or optional dualized steering.
The machine has a patent-pending articulated boom design that controls the vacuum hose. It allows a full, 180 degrees of boom travel and more than 200 degrees of hose reach while allowing fingertip hose positioning anywhere in a 10-foot radius. The design allows the vacuum hose to fold inward on itself, within the rear profile of the sweeper, during transportation, dumping or while not in use.
The vacuum hose on the Megawind has a maximum lift height of nearly 14 feet when the boom is completely unfolded. The standard heavy-duty flex hose is equipped with a manual rear-gate valve that allows the operator to cut off airflow to the hose and retain debris in the hopper during transport, without the use of a clamp-on blanking plate. Pendant controls include throttle up/down, shoulder in/out, elbow in/out, lift up/down and engine throttle control. A wireless remote control intended for added operator convenience is also available.
The system features a powerful fan with a rating of 30,000 CFM of airflow for removal of debris from catch basins.
The optional street sweeper system features ergonomic controls and Elgin Sweeper’s Memory Sweep, which allows the operator to resume all previous sweeper settings with one-touch control.
The machine is available with debris hopper capacities from 10 to 15 cubic yards. The hopper is constructed of 10-gauge steel walls and a 1/4-inch (6.35-mm) thick floor with drop-down screens for quick cleanup. Designed to maximize the life, durability, and functionality of the hopper, an optional LifeLiner hopper liner and finish system is available. Efficient dumping is intended with a 50-degree tilt angle.
Vactor Manufacturing offers the Vactor 2100 Plus CB, engineered to provide all of the benefits of the Vactor 2100 Plus combination sewer cleaner, including improved air flow, operator ergonomics, enhanced safety, smart truck design, and standard high dump on a tandem axle chassis. An improved air-routing system is designed to provide an efficient air flow path for both the single- and dual-stage fan or a positive displacement blower configuration. The machine is built with ergonomic controls for easy operation and maintenance.
Exclusive features of the machine include standard 600-gallon water capacity for single axle and standard 900-gallon capacity for tandem axle, up to 1,250-gallon optional capacity, and a wash-down system capable of 10 gallons per minute at 600 psi.
GapVax Inc.
The manufacturer’s MC Advanced Series combination jet-vac is equipped with a CAN Bus system, allowing the operator to observe and troubleshoot the entire system. The display screen controls the hydraulics, blower, and water pump operations with a complete set of gauges. All body functions, boom and hose reel functions, vacuum break, throttle, area and safety lighting are wirelessly controlled. Even with the wireless technology, the company stresses an emphasis on maintaining proportional boom and hose reel control.
A mid-ship transfer case directs the power of the engine to the blower and hydraulic system. The transfer case is rated at 500 continuous hp and the transfer case mount is vibration isolated with four isolators.
The machine also features a unitized cylindrical water/debris tank with a full longsill subframe, a 3/16-inch non-corroding stainless steel water compartment, and a 3/16-inch high-strength carbon steel debris compartment. It comes with a full-opening rear door; a non-corroding stainless steel ring is designed to ensure a liquid-tight seal. The unit also has dual lift cylinders to open the rear door.
The MC Advanced Series machine is equipped with a material-backed air inlet and a top-loaded debris compartment intended for maximum debris capacity. Material is loaded at the rear of the compartment for fast unloading. A debris compartment inlet diffuser is engineered to reduce material carryover.
For vacuum performance, the machine has a rotary lobe positive displacement blower and a direct shaft drive. The blower mount is vibration isolated by four isolators. A specifically engineered absorption silencer is used to maximize sound dampening.
A debris compartment inlet diffuser directs material from the airstream and a specifically engineered centrifugal separator forces the dust and mist from the airstream into a large-capacity compartment. Air passes a final micro-screen strainer before entering the blower.
The boom is designed to work as one with the chassis because the machine is equipped with a structural steel torque box. The boom also has heavy-duty dual lift cylinders, 180 degrees of rotation, 8-inch flow capacity, and 3/16-inch tube design engineered for minimum friction and long compartment life.
A high-pressure water pump designed to use recycled water is rated at 50 to 100 gpm at 2,000 to 3,000 psi. The pump is a positive displacement Tri-plex plunger style.
The machine also features 4-inch cross I-beams for rigidity, a full body pivot pin through the rear of the subframe for dumping stability, a double-acting three-stage dump cylinder intended to substantially extend the life of the chassis suspension, and a torque stabilization system.
Hi-Vac Corporation
New F-Series Aquatech Jet/Vac combination jetting and vacuuming units are designed to provide efficient cleaning of structures such as storm sewers.
Standard features include a continuous flow, triplex reciprocating water pump rated up to 80 gpm at 2,000 psi. They also have a flooded suction line with the water level above the pump. The units are designed with run-dry technology. Water tanks are constructed of high molecular density polyethylene. The entire volume and structure are located above the chassis frame and above the pump’s suction level. The tanks are guaranteed against corrosion, splitting, or cracking. The 10- to 15-yard-capacity debris body has a cylindrical design and is top front loading. The body is built with high-strength steel and is resistant to corrosion and abrasion. The machine has newer internal tank components for higher usable capacities.
The top-loading boom powers up and down, does not rise with debris body, and extends to 25 feet, 5 inches. Top loading is intended to provide even load distribution. The machines are equipped with single-engine drive, designed to decrease fuel consumption, maintenance expenses, sound levels, weight on the chassis, and initial chassis price. The machines have a simple modular design intended for ease of operation and maintenance, and maximum efficiency. A 180-degree rotating front mounted reel is included for easy unit placement. The reel capacity is designed and engineered for 800 feet of 1-inch hose. Hydraulic power tilt is included so that the reel can be easily moved to open the hood for daily inspection. A telescopic reel is optional. The units are supplied with positive displacement rotary lobe “Rootstype” blowers. The blowers are engineered to utilize minimal horsepower for maximum performance and increase efficiency.
An optional unloader valve allows for complete control of water flow and pressure independent from vacuum power. The valve permits the use of various nozzles for various applications.
Johnston North America
Johnston began manufacturing street sweepers in 1937 and began producing the world’s first vacuum street sweepers in 1958. The company has sold more than 3,000 units in North America. There, the company’s most popular models for addressing stormwater management are the VT651 Vacuum Sweeper, the RT655 Regenerative Air Sweeper, the C201 Compact Vacuum Sweeper, and the CN101 Sub-Compact Street Sweeper.
All of the models use a fan system to generate air flow that creates an internal negative pressure, drawing any debris caught under the vacuum nozzle–in the case of the RT655, under the 93-inch full-width sweeping hood–into an air stream and up into a 8.5-cubic-yard stainless steel debris hopper. The debris hoppers are warranted for the life of the sweeper.
The VT651 has a reported industry-low 79-Dba level outside the cab and 68-Dba level inside the cab. The larger sweepers feature direct-coupled impellor fans through an adjustment free step-up gearbox that is designed to maximize energy transfer and minimize fuel consumption all without the need for belt adjustments.
On all of these models, an optional catch basin cleaning hose is available. The idea is to allow catch basin cleaning in addition to street sweeping without the need to purchase separate pieces of equipment.
Schwarze Industries
This manufacturer’s A-series regenerative air sweepers continuously reuse the air created by the sweeper’s fan system, a system designed to reduce the amount of polluted exhaust air. The entire airblast and suction process takes place under the enclosed, full-width sweeping head, creating a sweeping path that reportedly is more than 50% wider than a typical vacuum sweeper’s broom and-head system.
The company’s sweepers also feature 44-inch gutter brooms and a large debris intake tube that is included to prevent clogging and allow them to easily handle bulky debris. For extremely heavy, packed-down debris, Schwarze sweepers offer the Gutter Broom Extension Override, which allows one or both gutter brooms to be operated inboard, directly in front of the sweeping head. This feature is activated by a switch in the cab. Most A-series sweepers may be outfitted with a patented Mechani-Pneumatic Powerhood that features a full-width windrow broom located inside the sweeping head upstream of the air pickup system; the broom is completely contained under the sweeping head, a feature engineered for environmental benefit.
An air bleeder system is designed to allow the addition of outside air in certain sweeping situations, such as during fall leaf removal and when sweeping light, dusty material.
High-dumping A-series sweeper models that offload directly into dump trucks are also available. Also available is a 12-V backup auxiliary system that operates the hydraulics in the event of a catastrophic hydraulic system failure and that allows the hopper to be offloaded without use of the auxiliary engine.
The company’s WhisperWheel sweeping system utilizes engineering modifications to the blower fan, the fan housing, and the airflow design of the entire debris path. The system is said to increase pickup power by as much as 7%, provide auxiliary engine fuel savings of up to 20%, and reduce sound output by more than 70%.
Stewart-Amos Sweeper Co.
The company offers chassis-mounted mechanical broom and regenerative air street sweepers. Stewart-Amos manufactures five PM10-certified Starfire mechanical broom units in 4-, 5-, and 6-cubic-yard hopper sizes, in single- or dual-engine versions. The sweepers are equipped with gutter brooms to direct curbside road debris to a large main broom that sweeps fine dust and large road soilage into an elevator system that deposits it into a debris hopper. The units have large water tanks and spray nozzles for dust control.
The Starfire S-4 is designed for compactness and maneuverability. It requires no CDL license to operate, cleans a 10-foot path, has a 4-cubic-yard debris hopper, and dumps up to 10 feet, 2 inches off the ground. The Starfire S-6 comes with either a single or dual engine, sweeps a 12-foot path, and dumps over 12 feet. Both S-6 models employ a unique top-loading elevator engineered to maximize debris loading and productivity.
All Starfire mechanical broom models are equipped with a three-shaft elevator system; the third shaft is positioned in the center of the elevator to better support the chain assembly and reduce chain link wear. This feature is also intended to minimize periodic maintenance by providing twice the amount of available chain adjustment compared with two-shaft designs. It is also designed to create a free flow zone that helps prevent clogging by larger debris.
Starfire models also have a quad scissor hopper lift system that uses four massive hopper scissors rather than two, a feature engineered to ensure hopper stability when dumping sticky, unbalanced, or wet loads. The system also allows for longer dump doors, which keep the sweeper body away from trucks and dumpsters and is designed to load receptacles more efficiently. Spring-balanced, auto-compensating gutter brooms adjust downward as the brush wears, a design intended to sweep curbs more effectively.
The company also manufactures two mid-sized regenerative air units mounted on non-CDL chassis. The Galaxy R-4 is a 4.65-cubic-yard-capacity high dump unit. The Galaxy R-6 has a 6.12-cubic-yard capacity and discharges at the chassis frame level. Both Galaxy models have standard stainless steel hoppers for easy cleaning, with a five-year no-rust-through factory warranty. Bolt-together stainless steel hopper panels are provided as an alternative to replacing damaged hoppers. Hopper top access doors automatically open when the hopper dumps for unlimited access to stainless steel debris separator screens and easier inspection and cleaning. These models are intended for tighter, more confined areas like cul-de-sacs, narrow streets, alleyways, and under tree-lined streets and low-hanging signs. These cabover trucks are also designed for high visibility and to eliminate the need for dual steering.
Super Products
The company’s Camel Sewer and Catch Basin Cleaners feature a Triplex water pump design intended to provide smooth-acting, surge-free flow and pressure. A positive displacement vacuum pump is engineered to ensure maximum vacuum and air flow at all engine speeds and allows material to be vacuumed above or below the surface.
The Camel also features an ejector plate unloading system engineered to safely and effectively remove all debris from the collector body with minimal cleanup. An internal body flush-out system is designed to make cleanup fast and easy. To prevent overfilling of the collector body, an automatic stainless steel dual float ball system is in place. The Camel is also available with the standard “tip-to-dump” method that raises the body up to a 50-degree angle with a telescopic hydraulic cylinder. All controls for discharging debris are located curbside of the chassis cab.
The Camel’s single-engine design is intended to lower sound levels and reduce maintenance and fuel consumption. This design also allows the vacuum, water, and hydraulic pumps to operate efficiently while the transmission is in neutral. A front-mounted control console is designed to make it easy and safe to operate many functions including the Camel’s water and vacuum pumps, PTO on/off switches, water flow control and pressure gauge, electronic engine throttle, and reel directional valve and speed controls. A wireless remote control system is also available.
A CAN Bus wiring system with an LED digital display screen replaces individual analog wiring systems and is configured to offer quick, convenient troubleshooting to reduce vehicle downtime.
The machine’s water tanks have a capacity up to 1,500 gallons (5,677 L) and are constructed of 3/8-inch (9.5-mm) rotationally molded, non-cross linked polyethylene with an ultraviolet stabilizer for strength and durability. The machine also comes with a wastewater recycling system intended to reduce the need for potable water.
Owners can customize their own storage for tools and accessories with a wide selection of different sized storage boxes. The debris collector body is constructed of 1/4-inch (19-mm) Exten high-strength, low-alloy, abrasion-resistant steel designed to withstand vacuum levels of 367 inches (93.22 mm) of water. Body sizes are available that offer debris capacities of 6.5 cubic yards (4.9 square meters), 10.8 cubic yards (8.2 square meters), and 16 cubic yards (12.2 square meters).
The rear door has aluminum tubing designed for ruggedness with available storage of up to 48 feet (14.6 meters). An optional hydraulic fold down rack is available.
The hose reel can be front- or mid-mounted on the unit. The front- mounted hose reel offers manual 180-degree rotation and has capacity up to 1,000 feet (304.8 meters) of 1-inch (25.4-mm) hose. The mid-mounted hose reel, which can hold 600 feet (182.9 meters) of 1-inch hose, features a hose reel tensioning and automatic level wind system.
With a “tube inside the tube” design, the Camel’s 8-foot hydraulic telescopic boom is capable of providing a vertical lift up to 22 feet (6.71 meters), extending up to 26 feet (7.92 meters), and lifting up to 1,000 pounds (454 kg). The 8-inch (203.22-mm) I.D. vacuum system comes with a reinforced elbow built for strength and durability. All boom positioning functions can be performed using the standard removable wired pendant or an optional wireless remote control.
The machine has three modes of conveying material. Like a centrifugal fan, the air conveyance mode moves material with air, which must be present to convey material. The pure vacuum mode moves material with vacuum, similar to a vane-type pump used in septic tank units. A combination of both methods, the Fluidizing Tube removes material from beneath the liquid surface by pure vacuum, then injects air into the system to carry material into the collector body via air conveyance.
A Super Pak dewatering system separates the material and water by allowing the driver to move the ejector plate and speed up the draining process, reportedly squeezing out up to 98% of liquid through a 6-inch drain located on the collector body. The system is designed to result in fewer trips to the dump site, lower operating fuel costs, and less messy dumped loads.
A high-torque, variable-speed, synchronous vacuum pump final drive is engineered to handle a wide variety of blower applications and ratings up to 27 inches Hg and 5,500 cubic feet per minute. It is designed to be quieter, with no gear backlash noise or high-speed gear whine. The simple design uses no intermediate gear boxes, clutches, or electronics.
Tymco
Tymco manufactures several regenerative air sweepers, from small parking lot sweepers like the Model 210h to larger machines like the Model 600, with a hopper capacity of 7.3 cubic yards and a 99-hp John Deere auxiliary engine. Because the regenerative air system uses little horsepower the Model 600 is designed around this smaller, more fuel-efficient engine.
The Model 600 uses full-width air blast and suction to pick up even heavy debris such as dirt and gravel. It is also available with an optional broom assist head. The operator can choose from within the cab when to use broom-assisted sweeping–for example, to loosen packed debris.
The unit’s 43-inch diameter gutter brooms also remove debris from curbs, gutters, and around obstacles such as parked vehicles. An optional tilt adjuster enables the broom to reach into deeper curbs and gutters. Other features of the gutter broom include automatically determined pressure required to dislodge debris, and automatic retraction and redeployment when the broom encounters an immovable object.
The Tymco Model 600 is the only sweeper with a high-efficiency centrifugal dust separator, which controls dust with less water.
Vac-Con
This manufacturer has sold nearly 7,000 units since 1986. Its Combination Machine employs a two-engine design that is engineered for operator safety and comfort. The deck-mounted auxiliary engine drives the water system, which features flow rates from 10 to 120 gallons per minute at 28 to 170 hp. Using the auxiliary engine to drive the water system allows the chassis engine to remain at idle during flushing, which reduces fuel usage, reduces heat exposure for the operator, and reduces noise. By running the system from the front operator’s station, the operator is safer because the task occurs away from oncoming traffic.
Currently the company offers two types of auxiliary engines: a 140-hp diesel engine or a 220-hp V-10 gasoline engine. With installation of an optional hydraulic pump, the chassis can be turned off, allowing for additional fuel savings of about 3 gallons per hour. Reducing the chassis idle time by three hours each day reduces the truck’s carbon footprint by 18 metric tons each year, according to the manufacturer.
The vacuum system is driven hydrostatically by the chassis engine. An exclusive three-stage centrifugal compressor or positive displacement rotary lobe blower generates vacuum, depending on the customer’s requirements. The company now offers a large displacement hydrostatic pump that allows the operator to run the chassis at much lower engine speeds, further enhancing fuel savings and noise abatement. The combination of a three-stage compressor and an optional stainless steel silencer is intended to further decrease noise emissions.
Water system options include debris body flushout and a low-pressure handgun. The addition of a hydro excavation package virtually turns a combination machine into a hydro excavator at a fraction of the cost of purchasing an additional machine. The operator can gain further insight to potential failures or blockages by installing the Inspector Cam video inspection system.
The Hi-Dump a dumping system allows the operator to dump the tank into a 60-inch-tall container, a configuration designed to allow the operator to keep the machine on the job flushing and vacuuming instead of transporting the spoils to landfills. The Omnibus operating system consists of CAN Bus technology that includes operational instruction, truck chassis interface, complete Vac-Con system diagnostics, wireless remote controls, and programmed safety features in one centrally mounted computer controller. The Power-Flex flexible telescopic boom has an articulating elbow similar to that of a backhoe. The boom can telescope 10 feet, extending its reach up to 28.5 feet, and articulate up to 110 degrees.
The Vanguard anti-microbial/anti-bacterial washdown system is designed to be an advancement in operator safety. This system allows the operator to wash down any tool or hose that has been in contact with into a storm or sanitary sewer system with Quaternary ammonia.
Wayne Sweepers
This relative newcomer to the sweeper market has had presence in the severe-duty truck market for more than 50 years. The company emphasizes its on-demand hydraulic technology that is designed for a more efficient use of hydraulics and fuel savings. The technology has been developed to make the operation of the control system, as well as pumps, more efficient. According to the manufacturer, the technology provides stormwater managers with diesel fuel savings of 3 to 5 gallons per truck per day.
Wayne also emphasizes its patented POD (power-on-demand) system that has been developed in partnership with Eaton Hydraulics, which is standard with all models. All of the manufacturer’s models are PM10-certified. On-screen, onboard diagnostics are possible without the need for an external computer, using a CAN Bus system for all sweeper controls, which reduces wiring and diagnostic time.
The manufacturer’s Gladiator sweeper features a 5-cubic-yard hopper, a 74-horsepower Kubota auxiliary engine, or an optional John Deere 99-hp engine; a squeegee-type conveyor system with replaceable flights; a 340-gallon water tank; a 60-inch main broom with 35.5-inch diameter; 44-inch-diameter dual gutter brooms; interchangeable broom and conveyor motors; a rear air suspension; 12,000 pounds of scissor lift capacity; advanced load-sensing hydraulics; and a multiplexed control system with a color LCD display. Options include an auxiliary front mount broom, a sweeper wash down system, a GPS integrated control system, in-cab broom down pressure control, and a broom miles swept meter. The company also offers its single-engine Warrior model, which has been in production for more than two years.
