What's in the water?

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Regular member
Nov 4, 2002
I thought I relax from our political discussions with some green issues which are closer to fishing and the environment.

If I and my 26,000 neighbours pour half a bottle of thick bleach down the toilet where does this stuff end up and what does it do to the environment? Is it is it handled by the sewage treatment process, or does it just kill the sewage treatment process?

Even if the bleach is OK, what happens if I pour a bottle of drain cleaner (caustic soda) down my outside drains. Where does this lot end up and what harm does it do to the environment?

Why have so many beautiful looking rivers and lakes got very few fish in them? It's not just cormorants, I know for sure. I live 500 yards from a nice little lake and a fine looking stretch of the River Mimram. The only fish in the lake are 4 or 5 carp some-one has illegal put in. There's no other fish, not even small ones. Then there's the river. It's seems to be lifeless apart from a few stocked rainbows (which I haven't seem myself).

Now this lake and stretch of river is in a dip alongside a very busy main road. All the water that runs off the road ends up in a couple of collection ponds above the lake which then feed into the river. They also often overflow into the lake. So I reckon the filthy polluted water off the road kills everything in passes through. What else would explain it?

This may not be the full story though. I was looking at the same river about a mile downstream at a hotel/conflab centre and its equally lifeless looking, apart from the odd stocked trout.

The deluge of chemicals and filth we put into our waterways must surely have something to do with the lack of fish. I can think of lots of places which should be teaming with fish and aquatic life, but aren't. There are some incredible looking backwaters of the Thames around Oxford (my home town), but they have practically no fish in them at all. Compare this to the waters of Scandinavia or closer to home in Eire. They are positively overflowing with fish which practically jump into your net

If we could go back 300 years and look at the same lifeless waters, I wonder what they'd have in them then.

Although we may have significantly cleaned up our bigger rivers since the 1950's and 60's, I reckon we are quietly destroying many of our waters with pollution which is doing untold damage. I am sure I read that the bag muck (fertiliser) used by most farmers is also pretty bad. Then there's the hormones in the water (from the pill I think) that's turning everything female? And isn't there something in unleaded petrol that is very, very bad quietly killing everything too, or is that just an urban tail?

Any thoughts anybody? Sorry if I've put to much down in one go. I'd really like to know about the fate of the bleach and the drain cleaner though.

Lid [:)]
Last edited:


19/08/02 - 25/08/10
In Memoriam
Aug 19, 2002
Hi Lid [:)]

I will try to explain what happens to your waste after it leaves your home. Bear with me as it is some time since I was last at a sewage works.
My father was an operative at the Great Billing sewage works for some 25/30 years, and in that time I used to pick him up from work when weather was bad, and other times just to help him out. It was during this time I found out how the sewage was processed.

When your waste, bath, toilet, washing up, washing machine water leaves your house it travels down a series of sewer drains, using gravity to help the flow, until it meets up with the "mains" this will be a pipe of up to 24"/36" in dia maybe bigger. In places it is pumped to help the flow to the sewage works.

On arrival at the works the drains then revert to the surface in the form of "U" shaped channels appx. 8'-9'x4', the effluent then passes through a device called a "rake" which simply removes any substantial solid content, usually rags, paper, metal and the like, it has not been unknown for a body and some of it's parts to have turned up before.

This solid material is lifted out of the way by a metal conveyor to a furnace where it is burned off.

The rest of the flow is then directed to huge settling tanks where the suspended solids in the effluent are allowed to settle, with the liquid part overflowing the lip of the tank and being pumped out to sprinklers, where it is sprayed over a bed of coke and charcoal mix, this acts as a filter.

The solids are collected and sent to huge tanks where they are heated and stirred up to produce methane gas for use by the plant.
When finished with they have the remaining liquid drained and returned to the process, with the solids being dumped on the land ajacent to the works.

The liquid part in the meantime is after being pumped through the sprinklers is then stored in huge tanks which contain aerobic (friendly, useful,) bacteria, where huge amounts of air are pumped through encouraging the bacteria to grow and feed on the "bad" bacteria in the water, this process is repeated several times until the water reaches an acceptable level of quality. It is in this part of the process where most harmfull entities are removed.

Basically your dirty water with all its bits and pieces in it, including your bleaches, drain cleaners and everything else shoved down the drained are dealt with by these little guys, I don't pretend to know all the answers on this subject chemically wise just the basics behined the process. I know that this process doesn't get out ALL the chemicals, so maybe some new process should be introduced. Most of the modern manufacturers have changed their products content to assist with this process

Sometimes your local sewage works offer an "open day" this might be a chance to find out more, or perhaps an e-mail to the local works will give you a more detailed answer.

Anyway hope this helps.

Born To Fish
Forced To Work
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