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Chapter 8: Environment, Health and Wellbeing
Private Wells
Private wells used for drinking water in Ireland remain
at risk of contamination.
There are approximately 170,000 private wells in Ireland,
of which at least 30% are estimated to be contaminated
by
E. coli
(EPA, 2015c; Hynds, 2012). Private wells are not
regulated under the European Communities (Drinking Water)
Regulations 2014 and are classified as “exempted supplies”.
This means that there is no requirement to monitor such
supplies, nor is there any regulatory supervision of such
supplies. In effect, this means that the well owner is solely
responsible for the quality of the well water.
Many private wells are at risk of contamination from
sources such as septic tanks, landspreading of slurry,
animals grazing near the wellhead, chemical storage and
fuel storage tanks. Private wells need to be properly sited,
constructed and maintained in order to reduce the risk of
contamination.
30% of private wells are
estimated to be contaminated
by E. coli.
Urban Waste Water
The effective management and treatment of our
waste waters is critical to the health of our waters,
our economy and our population.
Urban waste water is one of the principal pressures on
water quality in Ireland (EPA, 2015d) and also poses
a threat to human health. Sewage and other waste
waters contain microbiological and chemical substances
that can be harmful to health. Waste water collected in
urban areas must be treated in order to remove these
contaminants, prior to being discharged into receiving
water bodies. The treatment and disposal of waste water
in an environmentally sound manner is important not only
for human health but also for Ireland’s social and economic
development. Pollution from waste water treatment plants
arises where there is inadequate treatment; storm water
overflows operating incorrectly; or direct discharges of
untreated waste water.
Table 8.2
Chemical Contamination of Drinking Water – Risks and Intervention (Source: EPA, 2015c)
Chemical
Contaminant
Source
Risk/Impact
Action/Intervention
Trihalomethanes
(THMs)
By-product of the
disinfection process,
formed by the reaction of
chlorine (disinfectant) with
natural organic matter in
the water
Possible associations with
cancer – uncertain in terms
of causality
Water supplier should
aim to minimise THMs
by providing appropriate
treatment while not
compromising disinfection
Lead
Lead piping in distribution
systems and household
plumbing
Classified as “probably
carcinogenic”. Long-term
exposure can affect brain
development of infants,
young children and babies
in the womb
Replacement of lead piping
and interim mitigation
measures under the
National Lead Strategy
(June 2015) and Irish
Water’s Lead in Drinking
Water Mitigation Plan
Pesticides
Agricultural, commercial
and domestic use
Potential harmful health
effects depend on the
toxicology of the individual
pesticide
Protection of drinking
water sources from
pesticide contamination
using catchment-based
engagement efforts