Post Flood Draining

Jo_Mcflo · 09 Jan 2017, 1:27 pm

Anyone who lives in Melbourne would know there was a flood (somewhat) recently. Before the flood when I went into Dungeon there wasnt really a smell at all, but now after the flood theres a somewhat strong algae type of smell. After being in the drain for a bit I felt fine other than a slight weird feeling in my stomach (A day has passed, I dont feel it anymore). 2 weeks before though a mate of mine went in, this was just a few days after the flood, and he says his throat has been feeling pretty bad ever since (although it has become better). I know this isnt a medical forum, but should I be cautious about going in there again, or is this normal (especially after a flood)?
Anyways, thanks.
- Jo

Ritchie · 09 Jan 2017, 2:30 pm

I do alot of white water kayaking on flooded rivers, seen dead cows float by, car parts etc. Most likely a dead fox stuck somewhere festering away, or there could have been a stagnate pool up stream that was cut off for ages and since the flood it's muck has been released.

Panic! · 09 Jan 2017, 5:13 pm

Back in the day I did some research on this. Blue green algae is a type of nerve toxin that can make you sick. Also, after floods, deposits of heavy metals tend to be moved, which may be asorbed, also making you sick.

For more detail see: http://www.uer.ca/urbanadventure/www.ur ... polute.htm

Jo_Mcflo · 09 Jan 2017, 8:51 pm

Alright, thanks for the responses. I will be avoiding it for a bit, especially since I went back there today and could smell it from outside the drain. Although the outside area just a couple of meters towards Southern Dungeon seemed to be alright, took a few photos which I will be posting soon.

Aydun · 09 Jan 2017, 9:36 pm

By algae type of smell, do you mean rotten eggs?
That could indicate hydrogen sulfide, which can potentially be dangerous in confined spaces.

However it requires pretty high concentrations and usually comes along with other symptoms. I.e.:
https://www.osha.gov/SLTC/hydrogensulfide/hazards.html

Places like Rotorua and other geothermal areas smell because of hydrogen sulfide, but these places aren't at all dangerous.
It's only really in confined spaces where the lack of airflow can allow it to accumulate that it could potentially be dangerous.

Otherwise I'd hazard a guess at placebo/coincidence. Especially with such different symptoms.

I mean, for things like blue-green algae to make you unwell you'd have to drink a considerable amount.

Then again, doesn't hurt to be overly cautious!

Jo_Mcflo · 09 Jan 2017, 10:50 pm

Aydun wrote: ↑
09 Jan 2017, 9:36 pm
By algae type of smell, do you mean rotten eggs?

No, it didn't smell like rotten eggs, it didn't even smell bad, it was just a strong smell. I doubt it was hydrogen sulfide. Could definitely be placebo but that smell is to strong to be nothing. As Panic said it may be either the Blue green algae or heavy metals, but where the water was running looked more like moss (perhaps im confusing the two?). Heavy metals is definitely a possibility.
My conclusion, I have no idea, I will just wait until it clears out.

Mirror · 10 Jan 2017, 11:10 pm

Aydun wrote: ↑
09 Jan 2017, 9:36 pm
...That could indicate hydrogen sulfide, which can potentially be dangerous in confined spaces.[...]

Hydrogen Sulfide is deadly and can 'stun' your nasal receptors, if you smell rotten eggs get out. The smell may dissappear but that maybe as a result of your sense of smell failing not a lack of hydrogen sulfide. Unless you are certain you are clear of the source, you should leave.

ultraviolet · 11 Jan 2017, 4:24 pm

Floodwaters could contain rotted vegetation from upstream which turns the water dark and smelly as it decomposes. The decomposition uses up all the oxygen in the water leaving sulphide and also causes mass fish kills when it flows into the rivers. I think it's the bacteria feeding on the decomposed vegetation that leaves the suphide dissolved in the water as they use up the oxygen. And as the water flows the sulphide dissipates into the air causing that smell. So it will disappear but it does take time.

Anyway I'd stay out just in case.

Panic! · 11 Jan 2017, 4:52 pm

Wahoo. Holy carp there's a bunch of geniuses involved in UE. Lots more people get killed playing golf than UE. You don't expect golfers to be this informed about their hobby. Wonderful and informative advice here.

iso · 12 Jan 2017, 2:23 am

The smell you describe sounds like typical 'drain smell'. It's a mix of detergents and some volatile that the biofilm gives off. Would probably be more intense after a storm as all the dried detergent residue on the roads, etc. would dissolve in the runoff, which would also disturb the biofilm and make the drain smell more.

Hydrogen sulfide (H2S) is very characteristic, you'd be hard pressed to mistake it, it literally smells like rotten eggs. You do get used to it after a while and if the concentrations build up it will kill you. That said, the only times I've ever encountered it is when I've walked up a flooded drain in waders (Chameleon and Novest both come to mind) and the stuff bubbles up from where I've dredged up the silt. Otherwise I've never had a problem with it (most drains are fairly well ventilated by design).

I did Dwellers' Tomb the other night and even a few days after rain, the smell was pretty strong and the air hard to breathe. This was mostly due to the humidity though. Additionally, Dwellers' has an ERS (emergency relief structure) near its outfall, which makes it smell especially sewery. Lots of drains have these for discharging sewer runoff during peak flow periods. Dungeon has one too, but if I remember right it's way up some upstream branch. My usual response to this though => https://youtu.be/8E4k2zGahmc?t=40s

Heavy metals are another one I've never been sure about. They're definitely more sinister in their chronic rather than acute effects, but as to getting personally contaminated I'm not sure. The likely vector would be mercury and cadmium salts dissolved in the water vapour and then being inhaled (assuming you're not going around drinking drain water, which will put you in bed for a few days because of the high e. coli count).

In a nutshell, I'd just stay off the drains for a bit and you should be fine to start exploring again. The only thing that would keep me out is petroleum contamination (i.e. upstream Novest), open wounds and a compromised immune system.

Sorry about the lengthy post, I like nerding with this stuff. I won't give out my occupation on here, but I'll say it does require me to know this stuff.

Panic! · 12 Jan 2017, 3:31 pm

iso wrote: ↑
12 Jan 2017, 2:23 am
I won't give out my occupation on here, but I'll say it does require me to know this stuff.

My Guesses:
Melbourne Water geek / techi.
Secret agent for the Man.

Bangers · 05 Feb 2017, 4:27 pm

Heavy metals are a cumulative poison and will generally require regular exposure over a long period of time to become harmful.