Factorio Forums

With the 0.17 pollution changes, was it intentional to make the pollution clouds over water and concrete stick around long after a factory or mine shuts down? I've been seeing this since I converted this 0.15/0.16 railworld save to 0.17.4.

Going by the relevant prototype file, this doesn't seem intended.

They're probably just much more visible than before - check the actual values with debug's show-pollution-values ?

Pollution should stick around for 1.5 times longer than on grass, before being absorbed, so maybe that's the case? You can provide the save so we can investigate better.

But the truth is, that the pollution of concrete is 0. And since there is a minimum pollution to diffuse, pollution on a concrete chunk without trees will never go completely away.

Not sure if it should be considered a problem or not, concrete also might have some very little pollution consumption.

Ok, here is the save.
Edit: I guess the forum doesn't like 21mb files. "error parsing server response". I switched the compression from zip to 7z.

I suspect this is a result of two parts of pollution mechanic.

1, Pollution won't spread if it is below a certain threshold. this is to avoid pollution spreading across the map at the rate of tick.
2, Pollution will not dissipate over water. If pollution dissipation on a chunk is zero, it will only be able to spread, not dissipate.

As such, if water now has a pollution dissipation of zero, then any pollution there will spread out until it hits the minimum threshhold, and just sit there forever.

This might have been the case before, but pollution cloud used to be really faint at the edge, instead of around 50% opacity. So it would have required you to look closely.

Seems to work correctly. Leave it for long enough and the pollution is gone.
The pollution still stays on the concrete. To be decided if it's intended or not.