Water Pollution


With all our rainfall, Ireland’s got plenty of water, we all know that. However the quality of 30% of our rivers is not to acceptable standards. Water is precious for drinking, vital economically, wonderful for amenity and on top of all of that it’s just plain beautiful. We in Ireland seem to think that we can build houses and other buildings all over the countryside and use our soil and groundwater as an open sewer with no side effects though the problems in Galway have shown definitively that this is not the case. Intensive farming leading to concentrations of slurry and silage running off our farms and into the water system, add to that the spreading of chemicals in the form of fertilisers and pesticides and one can see why farming puts the biggest pressure on our water quality. We also build houses with no proper infrastructure. Each year over 10,000 new homes have been built in the countryside discharging millions of cubic metres of waste water into our now polluted groundwater systems. The role of the EPA is to monitor Ireland’s 8 river basins but as management control falls to Local Authorities, their powers are limited. The Moy river catchment, once a healthy waterway is now showing signs of stress. Martin McGarrigle of the EPA monitors our western rivers and lakes. Martin, the Moy river, has it got a big catchment? The Moy is one of the biggest catchments. In total I think it’s over 2,000 square kilometres, it’s massive. Including the lakes, including all the tributaries, so it’s a very big system. It’s the best salmon river probably in the country at the moment it’s a really fantastic system. So you’ve done loads of tests probably on this river here, this catchment. How many roughly? Hard to put a figure on this one but, I work in the west of Ireland I think I’ve done probably 10,000 tests. 10,000 tests? Using this. So this is one of them here? This is a regular site here on the Moy and it will be done once every 3 years. So where are you going to go? While the EPA has effected improvement of our severely polluted waters in recent years, our better quality rivers have somewhat declined. If our councils continue to allow one off housing they must insist that waste water treatment from these is of the highest possible standards. When small scale treatment plants are installed they must have an effective system in place for regular monitoring and maintenance. Martin what’s going on over here? This is an example of a small treatment plant that’s basically overloaded and it’s polluting the river. Unless the standards are set very strictly and unless they are actually adhered to as well you get river pollution. That’s one of the causes of river pollution that we’re investigating and trying to sort out under the Programme of Measures. And is the pipe discharging straight into the river from the treatment plant? Well the discharge should be treated to the standard that it’s okay to discharge it into the river that it’s not going to affect it. What if it breaks down? Well you get pollution. That’s why we have 30% of our rivers, it’s not the only reason, it’s one of the reasons that we have 30% of our river channel polluted. To get a true picture of what’s happening Martin works his way up river to one of the smaller streams that feed the system. Are you concerned about this tributary here? It’s one of these cases where it is diffuse pollution but we’re not quite sure exactly what the particular cause is. So you’re going to test now for different types of invertebrates? I’m going to take an invertebrate sample here and we’ll analyse the results. Okay we know from earlier on in the year that it is polluted but then it’s to try and track it down exactly what is causing it. The biggest threat to water quality is eutrophication, an over enrichment of nutrient that feeds algae due to phosphates and nitrates seeping into our waters from slurry, fertilisers, detergents and sewage. The samples Martin collects on a regular basis give a very clear indication of what’s going on. So what sort of creatures have you netted here? Okay well we have a fairly typical selection of lots of shrimps and some small mayflies and here we have a snail, a little thing called lymnaea which is a sign that there’s a fair amount of algae in the river. So any species in here causing you concern? Well there’s a few but I think the main thing is this filamentous algae there’s a huge amount of that on the bottom of the river. You can see it there. That’s just growing on the rock? I’ve just taken it off the stone there it’s quite luxuriant indicating that there’s a lot of nutrients coming down the system a lot more than there should be for a stream like this. Where do you think that nutrient is coming from? Well this is the investigative side of it now I mean there are a number of things in this catchment; there’s some forestry on peatland, there’s a lot of septic tanks. In the EPA lab in Castlebar the samples are analysed by the chemistry department and Martin records and logs his specimens. This is the sample we took from the main Moy it’s an example of extremely tolerant, these blood worms, these red guys particularly and these worms here, but these guys have haemoglobin that allows them to withstand very very low oxygen concentrations. A few others as well that appear tolerant they are like wood louse except that they live in water. They’re from the most serious forms of pollution really. Something serious is going on here because they don’t get to that size just overnight. It’s a really good indicator of nasty conditions. Over 80% of Ireland’s waste water is now receiving secondary treatment but most plants are not effective enough and are already overloaded and while the bigger industries are now licensed and have made positive changes, it’s the smaller and more diffuse sources that still cause most of the problems. To protect a vital resource such as water, our attitudes must change. We must learn from our European neighbours about strict planning and regulations of building development. Urgent upgrading of our defective waste water treatment systems must be a priority. We have got to reach a target of good quality water status by 2015 under the Water Framework Directive. Will we achieve this situation, we’ve 7 years to do it? It’s a tall order but I’d be optimistic enough I’d like to think that it wasn’t all in vain and we can get to that stage where we look back and say gosh did we ever let it get that bad.

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