Uncontrollable Water Pollution

[sabstion 46]

I have a massive, uncontrollable problem with water pollution.

Recently, the water pollution started rising out of nowhere, and spread across the whole tile. There doesn't seem to be any source. Water treatment plants don't do anything, and I have no idea what the cause is.

Here's the graph of the pollution:

And the eventual spread across the tile:

It increases quickly until the whole tile is red. If I demolish and dezone everything, the water pollution graph goes down, but the pollution already there doesn't go away:

The pollution goes way up as long as something is built or zoned; if there's nothing at all built, it goes down, but it shoots back up as soon as a build a single road tile, or school, or bus stop or whatever. It does the same if I zone a single tile. Subways and water pipes don't affect it, though, so it seems only surface buildings make a difference.

It only affects this single city; other cities, even those adjacent in the region, don't have the problem at all, and I tried obliterating the city (after backing it up) and the new city on the same tile didn't have this issue. I also tried building water pumps in an adjacent city and importing the water, and that water was fine, although the water pollution in this city didn't go away.

I've seen similar problems happen to other people, but not at this level. I've tried using radical water purifiers, removing my mods, duplicating the city, and every other method I can think of. I've put quite a bit of time into this city so I don't want to abandon it and I really don't know what to do. Any ideas out there?

[matias93 7,535]

That's, without doubt, file corruption, matches perfectly. Do you said that obliterating the city resolved it, and what I can see is that the city is, in fact, empty, so that's a first step in the right direction.

What I didn't understand correctly is if this behaviour repeats when you begin to build something on the already obliterated city. If is that the case, I would start by trying to build on the city tile with an alternate, empty, plugins folder, to discard a faulty plugin causing the issues.

If the contamination keeps even when not using plugins, somewhat weird happened to the city file, and the best option would be to export the full region to a SC4M or grayscale file with the SC4 Mapper application, and then import it back to create another region, to keep the geography while fixing the city files.

If, on the other hand, the problem resolves by not using plugins, you'll have to find which plugin is causing the problems. In that case, divide your plugins folder in halves and run the city with one and then the other, trying to replicate the contamination. If only appears on one of them, repeat the procedure with the faulty one, until arriving to the damaged plugin. If both halves have the same issue, you'll have to test all four quarters to find the causes. I know this is slow and boring, but is the faster way to find the problem without knowing it beforehand.

[sabstion 46]

16 minutes ago, matias93 said:

That's, without doubt, file corruption, matches perfectly. Do you said that obliterating the city resolved it, and what I can see is that the city is, in fact, empty, so that's a first step in the right direction.

What I didn't understand correctly is if this behaviour repeats when you begin to build something on the already obliterated city. If is that the case, I would start by trying to build on the city tile with an alternate, empty, plugins folder, to discard a faulty plugin causing the issues.

If the contamination keeps even when not using plugins, somewhat weird happened to the city file, and the best option would be to export the full region to a SC4M or grayscale file with the SC4 Mapper application, and then import it back to create another region, to keep the geography while fixing the city files.

If, on the other hand, the problem resolves by not using plugins, you'll have to find which plugin is causing the problems. In that case, divide your plugins folder in halves and run the city with one and then the other, trying to replicate the contamination. If only appears on one of them, repeat the procedure with the faulty one, until arriving to the damaged plugin. If both halves have the same issue, you'll have to test all four quarters to find the causes. I know this is slow and boring, but is the faster way to find the problem without knowing it beforehand.

Thanks for the reply.

It's definitely a file corruption issue. I've run the game without plugins to no avail and this is the only city affected. Obliterating the city also got rid of the problem.

I really want to keep the city as it's been built but I really don't know how to do that, if it's possible at all. I tried creating a new region with SC4M but that only lets me create an identical region without the development. If you know a way to duplicate the region while keeping the city development please let me know.

[matias93 7,535]

Sadly that's impossible (I've tried it several times after getting poxed and otherwise corrupted cities, to no avail). The best thing you can do is to take screenshots of all your development to get a guide to rebuild the city as it was (even if, for the same experience, one always ends wanting to deviate from the original in order to improve it).

To avoid future issues, get sure to have a clean plugins folder, without ill-modded lots, only save by using Ctrl + S (never save and exit!!), and do not delete or replace props or buildings before demolishing the lots on where they are used. All of those are known causes of file corruption, and they are all avoidable. If you find yourself demolishing lots with already deleted props or buildings, DO NOT SAVE THE CITY, close the game, reload the building or prop files as they were when plopped or grown, and just then demolish them on the game. Only after that, you can delete the files safely.