Because I'm a massive verification nerd who hates fun, here's a little thread on geolocating these photos that people are claiming aren't from Venice.
As @lauralarmo points out, some people are claiming this is actually in the town of Burano, not Venice itself, but how could we possibly verify that? Well it's pretty straightforward
Finding Burano isn't hard, a quick search on Google finds its location on Google Maps, with some nice photos that are similar to the ones shared in the original tweet. But we want to find the exact location of the photos. google.com/maps/place/Bur… 
To make our life easy, we'll start with an image with some obvious points of references, like a bridge over a canal, rare enough that it'll reduce potential search locations when we start looking.
Zoom into Burano, using the map view on Google Maps we can clearly see the bridges crossing the canals, giving us just a handful of locations to check out google.com/maps/place/Bur…
Using Google Street View we can hop between the bridges, and quickly find this image taken on one of the bridges. google.com/maps/@45.48607…
A side by side comparison of the original image and the Street View image clearly shows the buildings are exactly the same, confirming this photograph isn't taken in Venice, but from Fondamenta degli Assassini in Burano
Now, let's see if we can find another image, this one will be a little tougher as we've no bridge to help narrow down possible locations, so let's see who can beat me to it.
I'm going to start by assuming these could be the same pair of swans, and search the previously geolocated area for a match.
So we're looking for 3 building, painted orange, red, and pink in that order. Satellite imager isn't much use, but Google Earth has 3D buildings, that allows you to look at a larger area than Street View allows all at once
Within 7 minutes of my last tweet @PjotrMonster found it, the power of crowdsourcing in action. google.com/maps/place/Bur…
Just to be sure you can check the layout of doors and windows as well as the colour of the buildings. Even the cover over the door appears to be the same google.com/maps/place/Bur…
Let's up the challenge level, and see if we can find this photograph's location. It might seem difficult at first, but assuming this is Burano, there's only going to be so many bridges to look at, so we first check them out on Street View one by one.
So having checked the Google Street View imagery of every bridge in Burano I can say none of them appear to match the bridge in the third photograph. Also note the water colour is different from the swan photographs, so it appear this photograph isn't in Burano.
One thing that stood out about the bridge in the 3rd photo is the stone wall behind the bridge, which doesn't appear to be a feature of any of the bridges in Burano. So it's possible this photo is actually from Venice, but that would still need to be verified.
So you might give up at this point, but fortunately I have obsessive personality traits that make that difficult for me to do, so now I'm going to look at every bridge in Venice on Google Street View for a match. Come join the fun. google.com/maps/place/Bur…
To aid my quest/descent into madness due to self-isolation, it's possible to use 3D view on Google Street View to glide through the canals of Venice looking for similar bridges. It's just like being there, if you've got a significant visual impairment.
While I've been faffing about on Google Earth 3D view, other people have found a potential location, and it looks good, but I need to be really REALLY sure
A quick Google of "ponte dei ferali venezia" brings up plenty of images that seem similar, but how do I know this isn't just another very similar bridge? Well, I need to find close up photographs of the brickwork and other features and match it perfectly with the original image.
We can compare the position of metal fixtures to the brick work on the first result for "ponte dei ferali venezia" on Google Images, and see it matches perfectly. Even individual patterns and damage on the bricks and masonry match.
So we can say these two photographs show the same location, but let's go one step further and, to be as certain as we can be without actually going there, find it on Google Street View.
A simple search on Google Maps finds the location, and even though we can't get a view of the side of the bridge, we can find a view on the bridge the clearly fits the same location as seen in the photograph from Google that matches the original photograph google.com/maps/@45.43545…
Therefore we can verify it's in Venice, and as the claim in the original tweet was the water is less polluted now. A neat trick on Google Street View is historical imagery, that lets you check the water out in 2013 and 2018 google.com/maps/@45.43545…
There's also plenty of images on Google that show the water in a similar state, so the claim the water quality has improved is at least visually apparent.
I would say this one would be impossible to geolocate, but I'm sure there's some people out there who would be able to find it, given enough time.
I mean, I'm already finding these two poles very enticing google.com/maps/@45.43545…
And finally, does this confirm the pictures are taken in Venice or not? Well Burano is part of the Metropolitan City of Venice, so technically it's correct, even though it's not part of what most people would think of as THE Venice.
If you've had the patience to read through this thread you might also have the patience to verify photographs and videos while you're trapped inside, and the Bellingcat Online Investigation Toolkit is a great place to start docs.google.com/document/d/1Bf…
You can also find handy guides and case studies on Bellingcat, like this guide to the best image search engines bellingcat.com/resources/how-…
If you've enjoyed this thread and are looking for something do to during your self-isolation, our podcast on MH17 demonstrates how much you can do with open source investigation, available on all good podcasting apps podcasts.apple.com/gb/podcast/the…
