Replacing Rising Main?

[None]

Hello,

Basically we have a bacterial slime build up along our rising main, which, when it flares up, makes our water slimy and horrible to wash in/drink etc. It probably happened some years ago when the house was left idle, ie stagnation occurred. The only thing that temporarily helps is turning off the water at the outside stopcock, and back on again after opening the garden tap. The water flows through at full whack, and this clears the problem, albeit only for a few days...

Should I replace the whole rising main, or come up with something a little more cost effective? Its doing me nut.

[clot]

I need more information to understand what is going on. What do you mean by a rising main? Is this from a public or private supply? If from public, there should be sufficient disinfection to prevent bacterial growth in the supply pipe. That you mention a stopcock suggests a public supply - but not necessarily the case. I'm loath to provide advice without a better picture of your situation.

Replacing the rising main would do nothing, if you have a continued supply water quality problem. More info. please.

[None]

By rising main I mean the supply pipe from the outside stopcock (driveway) to the attic tank and kitchen sink. It is from a public mains supply, and the neighbours do not have this problem. When I flush this pipe out through the back of the house at the highest pressure possible, the water loses the 'sliminess.' There isn't much of a chlorine residual, it was tested very low (0.02 mg/l or something), so that has probably contributed.

I just find it strange that when I do this, that the quality improves so much for a few days, then goes back to its previous state.

[<me9]

If you could isolate the pipe at the stopcock and fill it with a chlorine solution for a couple of hours, then thoroughly flush the pipe it could improve matters. What type of pipe is it, and who owns the stopcock? Is it of a WRC approved type, and could it be changed as well?

[None]

It seems to be black plastic LDPE type, I think, and measures 3/4 in. Not sure what WRC approved means, sorry. We own the stopcock. How could we enter the chlorine solution without breaking into the pipe? It would be great to get this done with as little disruption as possible.

[Doctor Drivel]

You have LDPE enter the house from the street. I assume a stop c*ck in the garden or pavement. Inside the house another stop c*ck. From this copper pipe to the tank, cold kitchen tap, etc.

Disconnect the pipe after the stopcock into the house. Drain the water. Cap up the pipe that runs into the house. From the tank pour the solution down the pipe. Leave and let the solution do its stuff.

The pipe from the underground stopcock to the house stopcock. You may be able to push a tube down this to the street stopcock. Blow down the tube and the water comes out of the pipe back up around the pipe; well most of it. Again pour down solution. leave. Connect everything back up after and flush through, If it re-emerges then contact the water people as it is on their side.

[None]

My first reply didnt seem to go through. Basically two things Doctor... firstly do you know what solution would be safe and effective? And also regarding the tube, would it have to long enough to actually reach the pavment stopcock from the kitchen??

[Doctor Drivel]

See Kamco, they would make the appropriate liquid.

I would think so, or as far down as you can get. You have to get the water out, or most of it, and then pour down the liquid.

[None]

The stopcock in the kitchen is tricky to access, being behind the utensil drawers, that could be a pain...

How much solution (presumably chlorine tabs) would need to be poured down? I mean the pipe length from kitchen to pavement must be about

25-30 feet.

Oh and finally, how long should I let the disinfectant 'do its stuff' in such a lengthy set of pipe runs? Cheers.

[clot]

Sorry None, I should have checked your name before replying. Still having the problem, I see. Does the water service accept that you have a problem? I appreciate that your neighbours are not getting the same difficulty, but it is possible that you are on a balance point as previously discussed and thus receiving "old water" so that the chlorine content has been all but consumed. It would seem to me that the main and your service pipe are in need of an air scour. Could you see whether the water dept. will do this?

[None]

Hi clot, Yeah I didnt actually check your name either, lol. Anyway, would an air scour involve much disruption to the road? Our neighbours are very closely all around us too, so I don't really think that there would be much difference in our chlorine content tbh. The water depot doesn't accept that we have a problem, saying our test results back in June were 'clear.' The chlorine tested very, very low, and that was no surprise as you can never smell or taste it really.

Would it even be possible to air scour our individual service pipe though?

[clot]

I honestly don't know I'm afraid. Might be time to do some googling for "air scour"/ plumbing contractors and the like. I've just been googling for chlorine guidelines in E&W and could not find anything - must admit I didn't go into every crevice. It does not appear that the chlorine issue has not moved on since I was involved in the potable supplies side of things.

I seem to remember that we set a standard of either 0.4 or 0.6 mg/l leaving the treatment works and from samples in customers' taps would expect a concentration of 0.1 mg/l as a minimum. At the level you are quoting, I would be concerned about the potential for bacterial growth. What did the water dept. say about 0.02? Do they have internal target minima? I would be leaning on Dublin's water dept. with that sort of concentration.

[None]

They dismissed my notion of introducing a chlorine booster in the area, didn't even comment on it really. We have no water votes or laws here it seems. It depends where you live I suppose. It seems I got spectacularly unlucky on this one. What is strange is that the quality can be good, but only after I turn off the outside stopcock, pull out the washing machine hose in the garden shed, go back out front and open the stopcock again. This I suppose has the effect of 'flushing' the pipe through, but is extremely tedious.

The problem seems so obvious: we need more of a chlorine residual, but they aren't going to listen to me, believing that giving a few flushes to the mains every couple of months is more than enough. I'm sick of this.

[clot]

Can you explain this bit in more detail? The washing machine is in the shed - how is it fed? Length and diameter of pipe? Do you mean the flexible cold supply hose? How often is this used and any other details that seem relevant.

This I suppose has the effect of 'flushing'

[None]

The washing machine is fed from the mains, is the last point of use for the water downstairs, and is used at least once a day. It was only installed there back in February, and we were having the same problems beforehand. Yes, Im talking about a flexible cold supply hose attached to the main line.

Back in December, I was replacing the old washing machine, and a load of dark crud came out of the inlet cold pipe feed to it. It was then that I began flushing out this pipe (originally into the kitchen sink, when it was located beside it), now I flush it out into the flower bed in the garden.

It helps to do this more when the water pressure is at its highest, late at night. I suppose this doesn't make much sense in the grand scheme of things though!

[clot]

Good, you've eliminated that as an issue! I just wondered whether this was a significant deadleg that could be a cause of the problem. It's frequency of use seems to eliminate it as well. I can appreciate why you get the best flushing effect when the pressure is high - that makes sense. You will be able to slough off a greater amount of film that may be developing in both the main and service pipe.

I guess the neighbours have got used to your midnight capers in the garden!

[None]

Any opinion on whether I should go the 'disinfecting of service pipe route?' It seems as if it is possible to do this, hard work, but not expensive. With the plentiful amount of houses around the neighbourhood and the road, the main surely gets enough flow to clean it pretty well.

[clot]

You are only going to get temporary relief, I'm afraid. It might attract the interest of the Water Dept., if they thought that backsyphonage from your activities into the main might affect the quality of water to your neighbours! Could be double edged - "we'll have to do something about his supply before this gets out of hand" sort of thing and also a stern warning not to affect the quality of water in their main! Have you googled plumbers/ water engineering contractors re air scour. I really think that would be the way to go if possible. Could be a solution for several years - but not permanent.

[None]

But if the neighbours arent experiencing these problems(and our neighbours to our left have their stopcock right beside ours!) surely either fully disinfecting the pipe, or replacing it would have a good effect?

[clot]

Now that's something I don't recall in previous dialogue! Are your houses of a similar age? Has your neighbour had his service pipe replaced? Might not be so obvious in that it might have been replaced if a new driveway was put in at some stage in the past as a result of a burst when doing the work!

I don't want to jump to conclusions. What is the length of your service pipe? Is it significantly longer than your neighbour's? This is beginning to suggest that you might get relief from replacing your service pipe, but let's be careful. I can't recall, did you tell me what it is made of and how old it is? Are you certain that the stopcock in the street only services your house? I don't know the layout and if you are in a "town house" situation, you might be on a common feed to two or three other houses.