The design and development of your neighborhood garbage truck
One of things my three-year-old looks forward to on a Tuesday morning is watching the various waste-collection trucks parade up and down the street. The trucks’ back-up warnings, hydraulic arms and flashing lights always attract at least a few kids to their front doors or porches to witness these hulking machines do their work. Between garbage and recycling, rear- and side-loading trucks, our neighborhood is serviced by a variety of designs, which are still only the a few of the many iterations of garbage truck designs.
The earliest waste collectors were basically working with what containers were readily available. Horse-drawn carts were sent around towns to pick up the trash that was discarded in the streets or yards, since most households either buried or burned their trash at home. It wasn’t until 1875 that Britain started designating specific garbage receptacles, followed shortly after by some large-scale incinerators. Even with a collection concept in place, the first garbage trucks obviously still had to wait for trucks to be invented.
Trucks moving trash
Around 1914, large trucks started being employed for trash collection, although many of those trucks weren’t any more specialized than a pickup, or maybe a dump truck. The cargo areas were open, which made the trucks magnets for flies, rats and anything else drawn to the strong smell that would build up as trash was collected. In response, the first big innovation in garbage trucks was to come up with some sort of cover or lid mechanism. With higher population density in Europe, there was more immediate demand for more pleasant trucks, but they slowly made their way across the United States by the 1930s.
With the smell of mobile refuse being contained, the next improvement in garbage truck design was for the sanitation workers who used the trucks (who probably like the covered trash too.) Loading the original trucks meant lifting up trash cans shoulder level to empty them into the truck, over and over, all day long. This was exhausting, and over time really slowed down trash collection. The answer was to add external hoppers to the trucks. The hopper was basically a huge collection bucket that could move down to a more convenient height, and then be raised up to dump trash into the truck from an opening at the top. This required some hydraulic arms to move the hopper up, but that also got it out of the way of the back of the truck for when garbage was being dumped at the end of a route. These designs caught on in the 1930s and 1940s, but the way the trash was carried left room for further improvement.
Hopper trucks, and the side-loading trucks that also went into use in the 1940s, would often end up with trash being badly distributed in the truck. It made the trucks off-balance, and meant that available space was being wasted. The first answer for this was to install huge corkscrew mechanisms inside, which would separate and churn the trash so that it was spread evenly throughout the cargo area. Beyond these rotary loaders, the next big push was to install full-blown compactors. Compactors not only made sure you were making good use of all the available space in the truck, but also meant that a truck could pick up a lot more trash before needing to unload.
Dawn of the dumpster
In the 1950s, a man named George Dempster revisited the external hopper concept, separating the hopper it from the truck itself. The Dempster-Dumpsters could sit and be filled at any appropriate location like the dumpsters we try to ignore in alleys today. Hydraulic hooks on the truck then pick up a dumpster, lift and empty it into an opening at the top of the truck. Much less work had to be done by garbage collectors themselves, speeding up the whole process of waste collection. Since the first Dempster trucks, these front end loading designs have become some of the most popular trucks for waste management. The one thing they’ve really dropped from the first garbage trucks is the tipping mechanism. The compacting blades can now push trash right out a back hatch, meaning the first bit of specialization from over 100 years ago has finally been replaced.
People are, sadly, making more trash than ever, so there’s little doubt garbage trucks are really going to slow down either. Aside from more automated loading mechanisms, such as rear- and side-loading arms, some of the next big innovations may be in the engines themselves.
Source: History of refuse collection (or the garbage truck):, TIgerdude.com