Buy one for your favourite city/ies.
In addition to garbage pickup, they automatically remove scarred land caused by fires, nukes, etc.
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Landfill
I try to avoid, as I don't like swiping. Best option for small cities on a budget though. Plus a cool animation!
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Incinerator
Best bang for the buck. Place pollution fighting tools such as Avocado Park around them, and you can even place them near residential zones. They use less space and can easily be fit in already built cities.
Spread these things out on larger maps requiring more than one. Building in a line along a road works alright, but building them in a square or triangle will cause the waste disposal influence to overflow (turn red when viewing waste disposal influence) and thus cause areas where garbage will not be automatically collected.
I think the waste management buildings should have significantly longer range of automatic collection, as this can become a large problem when building a large city, or possibly there can be a "Garbage truck depot" building that increases range. Garbage trucks could also go around the city rather than from one waste management building to another.
A feature which I really think should be added is to be able to send garbage from your city to other cities in a similar way to water and power.
I just hope Lobby will provide plugin support in garbage system in the next update, if not in the upcoming future. Then we could all come out with a better garbage plugin system than in the game