It is widely recognised that protecting drinking water at its source is the number one method of ensuring that a high-quality drinking water supply is achieved. The National Federation of Group Water Schemes (NFGWS) is actively involved in promoting source protection amongst the group water sector in Ireland. Presently Phase II of the new “Drinking Water Source Protection Pilot Project” is underway. This pilot will involve source protection planning for both groundwater and surface water sourced Group Water Schemes (GWSs).
Stranooden GWS has been selected as the pilot site for the surface water aspect of the project. Patrick McCabe has been appointed by Stranooden GWS to oversee the project and will be supported throughout its duration by both the NFGWS and Dundalk Institute of Technology (DkIT). The project will involve two key aspects:
The scheme abstracts its water from White Lough (also known as Baird Shore), where it’s then pumped to its water treatment plant in Corcaghan. Eight groundwater supplied GWSs, located in Co. Roscommon and Co. Westmeath have also been included in this national initiative, with this aspect of the work being conducted by Tobin Consulting Engineers, the Geological Survey of Ireland (GSI) and The NFGWS.
There are a number of reasons why Stranooden GWS was selected to pilot the surface water aspect of the project. As part of Phase I of the project, each GWS throughout the country that abstracts water from a lake source had their lake catchments delineated. A lake catchment simply means the area of land that drains into a river and its tributaries which then flows into a lake. When this exercise is carried out for White Lough it can be seen that the lake catchment is approximately 125km2 in area, with the catchment spanning from Corcaghan to Tullycorbet to Doohamlet, through Ballybay and down to just outside of Rockcorry were the lake is situated.
It is worth noting that all harmful activities within a lake catchment can have a negative effect on the lake. Given the size of the White Lough catchment the potential for harmful activities is increased. In Ireland, the principle causes of water quality deterioration are associated with nutrient inputs from agriculture, domestic and urban wastewater discharges, urban waste water misconnections and forestry. A large number of these pressures are thought to exist within the White Lough catchment. Currently, White Lough is classified as being of ‘Poor’ water quality status due to nutrient enrichment. Consequently, White Lough is seen as a challenging catchment due to its size and water quality issues and therefore suited in its selection as a pilot site.
Monaghan County Council are the supervisory authority for all private GWSs in Co. Monaghan. As part their role, Monaghan Co. Co. take a number of water samples each year from the Stranooden GWS’s treated drinking water network. During this testing, MCPA was in detected in certain water samples taken in 2017 and 2018. MCPA is a selective herbicide, commonly used in Ireland as a rush killer, but is also found in domestic herbicide products. Since March 2018, Stranooden GWS have carried out weekly sampling on the numerous streams and rivers that flow into White Lough to try and determine which parts of the catchment may be contributing mostly towards the problem.
The treatment plant used by Stranooden GWS is a Dissolved Air Filtration (DAF) plant. Unfortunately, this type of treatment system is not suitable for removing MCPA from the raw water entering the facility. Therefore, if MCPA is in the drinking water source, it may end up in the scheme’s drinking water, even after treatment.
While, exceedances of the E.U Drinking Water Regulations for MCPA have been detected by both Monaghan Co. Co. and Stranooden GWS, it is worth noting that no exceedances in the World Health Organisation (WHO) guideline value for MCPA has been detected and as such it is not envisaged that the levels currently found in our water present a health risk. However, caution should be exercised as the exceedances in the E.U Drinking Water Regulations found, signifies that certain practices in the catchment are leading to contamination.
Another problem faced by Stranooden GWS in relation to our drinking water surrounds the issue of trihalimethanes (THMs). THMs are compounds which may be formed when water that is high in organic content is treated with chlorine. Given that there are high levels of coliforms present in White Lough, Stranooden GWS uses chlorine to remove these coliforms prior to the distribution to its members. Similarly, high levels of organic matter can also be present in White Lough. This combination of organic matter and chlorine has on occasion resulted in an exceedance in the THM drinking water limit. The short-term health effects of THMs in drinking water are rare, however the effect of long-term exposure is not yet fully understood. With that being said, Stranooden GWS are keen to address the issue so that it doesn’t become a long-term problem.
The overall objective of the project is to develop an Integrated Catchment Management Plan that will result in the improvement of the scheme’s drinking water source (i.e. White Lough). It is hoped that as a result, the levels of nutrients, coliforms and herbicides detected within the lake will be reduced. If this can be achieved, Stranooden GWS envisage that the drinking water we supply to our members will be of a higher quality in terms of both potability and safety.
In order to achieve this, Stranooden GWS believe that interaction with the communities that live and work within the lake’s catchment will be key. Stranooden GWS staff are currently out on the ground, mapping the exact routes of the numerous streams and rivers that flow into White Lough as well as talking to the landowners adjacent to these channels. This work will continue over the next number of months.
To be successful in our approach, Stranooden GWS will not solely be focussing on agricultural pressures but will be looking at the catchment as a whole. For example, ineffective domestic waste water treatment systems (DWWTS) may be contributing to our problem. In 2016 the NFGWS commenced a DWWTS Education and Desludging Programme. As part of this initiative people where afforded the opportunity to sign up to have their septic tank desludged as part of a community wide bundle approach. By signing up to this scheme, participants availed of significant savings (up to 50%) on the cost of desludging. Stranooden GWS are keen to offer this service its members.
Through the development of a catchment plan specific to Stranooden GWS, it is anticipated that the findings obtained from the project will be used to develop a template and guidance for the development of source protection plans for all surface water supplied GWSs. Similarly, the learning obtained from the pilots underway in Co. Roscommon and Co. Westmeath will be utilised in the development of guidance for groundwater supplied GWSs.
If you would like to learn more about this project, please get in touch. You can find our contact details on the Contact Page of this website and why not follow us on the Stranooden GWS – Source Protection Pilot Project Facebook page or follow us on our Twitter handle @Stranooden. We will also be exhibiting a stand at the Cavan Monaghan Science Festival event that is due to take place at the Tanagh Outdoor Education Centre in Cootehill on the 16th of November 2018. Please come along if you have any questions.
Evidence of nutrient enrichment of the Dromore River, which flows into White Lough a short distance away. (Photo taken in July 2018 at Balladian Bridge).
The catchment operational group that will help advise and oversee the development of a source protection plan for Stranooden GWS. (Photo taken at the inaugural operational group meeting which took place at the Ballybay Wetlands Centre on the 6th of September 2018).