Saturday, 22 July 2017

TGWS water quality problems: more info about short & long term solutions


Some additional information about strategy to address current problems in short and long term.

To be clear, none of the problems we're currently experiencing are unusual - just unexpected. Many public water supplies have the same issues and there are off the shelf solutions; the problem is that  right now we don't have them in place.

In essence, our situation could be summarised by saying that we're missing one last piece of the jigsaw – a piece we didn't realise was needed until the recent problems, and it caught us unawares. All of the previous work that has been done was necessary is - & will be - needed, but without that last piece the picture is incomplete, i.e. we will not see the full benefit until everything is in place.

However, even with the full support of the council a full treatment solution will take time to implement: the very earliest this could be delivered is approx. 5 weeks from now, but could potentially take double that.

In the intervening period we are subject to the vagaries of an Irish summer, which is clearly not acceptable. Therefore, at last Tuesdays meeting, a vote was passed to pursue an interim solution which could be implemented in a few days – once funding is in place.

INTERIM SOLUTION
The old spring source flows into a larger river - the Castlelodge; the proposal is to pump from this, using a borehole pump laid horizontally into the riverbed, into the raw water tank. The most suitable location is upstream of the road crossing approx. 400m away, in front of Killian Fordes house, whose suggestion this was & who has kindly offered access to power supply.

The water will have time to settle in the raw water tank before being pumped on into to the network (using the old pump, still in situ) via the existing UV & chlorine treatment.

The interim solution will only remain in place until such time as the necessary treatment plant can be commissioned.

Important: we remain on a boil notice, in the meantime although the river water has slight colour, but is odour & sediment free. Even so, next week a sample will be sent for analysis to ensure there are no surprises.

We have a budget price for the necessary work, which includes installation & removal inc. all necessary plumbing and electrical work and hire of pump. We will have to purchase the pipe but this will not be wasted: a section of the network along Blakemount Rd is of insufficient bore and this can be used for the upgrade once full solution is up & running.

FULL SOLUTION
Although it this is a seasonal issue, it is worth noting that the water levels are exceptionally low right now – the lowest since 2012 or '13. Quality will recover (water quality was very good in first months after commissioning) however we need to be able to adequately treat the water in all circumstances, the hope is that the current circumstance represents something very near a worst case scenario.

As of this evening we have the test results from the first samples, which included the most important indicators of water quality, so the treatment solution can start to be defined. However, having been caught out once we will proceed with a full panel test to – as much as is possible – ensure there no more nasty surprises.

The good news is that whilst there is a question mark over the financial support available for that interim solution, all treatment related costs are supported at 100% - so no time will be lost whilst struggle to raise our stake.

The exception is ancillary costs: the existing pumphouse is getting crowded will likely not be able to accommodate all the new equipment required. A small container is probably the most effective solution and will qualify for 85% support, so the schemes stake will likely be in the hundreds rather than thousands.

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