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Water
Quality Certification
Water Quality Certification and Water
Quality Testing Treatment of the following water types:
Drinking
Water : Leisure
Water : Wastewater/Effluent
Drinking
Water
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Drinking water must by law meet
quality standards. Water providers have legal
responsibilities to ensure that drinking water
meet the statutory quality parameters set out
in the legislation. Relevant regulations:
- SI 439 of 2000
- The Drinking Water Directive
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Typical Water Quality Issues
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Cryptosporidium
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Guardia
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Chlorine by-products
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Chlorine
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Tastes
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Odours
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Turbidity
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Colour
Banish
with Reverse Osmosis
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Leisure
Water
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Bathing water such as beaches and
pools under municipal control, must meet the quality
standards set out in the Bathing
Water Directive. However, leisure water
quality of privately operated leisure centres,
as indicated by relevant chemical parameters and
by hygiene indicators, such as E. Coli and Pseudomonas,
is not subject to legal control, except insofar
as such facilities present a threat to public
health.
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Many privately operated pools and
spas register to the White Flag Standard and conform
to the recommendations of the Pool Water Treatment Advisory
Group.
Relevant regulations:
- Bathing Water Directive
- Public Health Regulations
White Flag Standard promoted by:
ILAM
Ireland (Institute of Leisure and Amenity Management)
EVIAN
mineral water
An
Taisce
The Pool Water Treatment Advisory Group (PWTAG)
There are no regulations in existence
which apply directly to leisure water used in pools
and spas. The Bathing Water Directive does not apply
here, though public health regulations are relevant
should leisure water pose a threat to health.
There are guidelines in place and voluntary
schemes such as the White Flag administered by ILAM.
Those leisure centres registered to the White Flag standard
are required to check their leisure water quality regularly.
The British Standard Institute Code of
Practice: PAS39:2003 is relevant. The Pool Water Treatment
Advisory Group (PWTAG) also recommend controls be placed
on pool chemicals a possible pathogens.
There are two broad areas which may require
attention:
1. Chemical content of the pool
or spa water
2. The issue of hygiene
1. Chemicals
In order to maintain leisure water in a satisfactory
condition, chemicals are added, mainly chlorine or bromine
to ensure optimum hygiene practices. Ozone is also used
to disinfect leisure water.
Chlorine is most commonly used as it is
very effective and persists, maintaining its disinfection
power long after dosing.
It is generally necessary to control the
pH of leisure water for bather comfort and to reduce
corrosivity. Addition of acids and bases are frequently
required to maintain the pH in the region of 7.2 to
7.4.
| 2.
Hygiene |
| Micro-organisms
that are classified as pathogens must be controlled
in leisure water. Those targeted are E. Coli, pseudomonas
and staphylococcus. Pseudomonas can be difficult
to control and is known to cause throat and ear
infections in those who succumb. Chlorine is very
effective in controlling these pathogens, bromine
less so. Constant vigilance is important in the
pool operator's endeavours to maintain leisure water
quality at the highest international standards.
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Pseudomonas by Visual
Immunoasay (VIA) |
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Coilform -
Free
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E. Coli -
Contaminated
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The range of data requiring checks and
the limits are given in the table below:
| Parameter |
PWTAG recommended |
Reason for ranges |
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| Free chlorine
mg/L |
Min. of 0.5
but should be between 1.5 and 2.0 mg/L chlorine |
Effective kill
of micro-organisms |
| Total chlorine
mg/L |
Less than twice
the free chlorine level |
Measure of the
original chlorine dosing level |
| Combined chlorine
mg/L |
Should be less
than half the free-chlorine value |
Measure of the
amine/ammonia load. |
| Calcium hardness
mg/L |
>40 mg/L
and <150 mg/L CaCO3 |
Pool non-epoxy
cement corrosion |
| pH |
7.2-7.8 |
Ensure effective
chlorine action and flocculation |
| Alkalinity (mg/L
CaCO3) |
>75 and <200
mg/L CaCO3 |
pH adjustment
downwards. |
| General
Coliforms (CFU/100 ml) |
<1 |
Health
and safety requirements |
| E.Coli (CFU/100
ml) |
<1 |
Health and safety
requirements |
| Pseudomonas
aeruginosa (Present/Absent) |
Absent |
Health and safety
requirements |
| Conductivity
(?S/cm) |
<4300?S/cm |
See TDS |
| TDS (mg/L) |
No more than
1000mg/L above the intake water |
High TDS does
marginally encourage corrosion (<3000 mg/L) |
| Sulphate (mg/L) |
As low as possible. |
Corrosion of
non-epoxy pool cement/grout |
| Temperature
(Celsius) |
27-30 Celsius |
Bather comfort |
| Turbidity (NTU) |
None |
Appearance of
the water |
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The issue of corrosivity may be an issue
for pool infra-structure. High sulphates will affect
cement grouting. Low pH low alkalinity, low hardness
will mean that leisure water is corrosive and will attack
metal pipe-work, though stainless steel will not be
affected.
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Wastewater/Effluent
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Waste water whether discharged directly to sewer
or directly to a water course or to ground must
meet quality standards by law. Those discharging
directly to the environment must have treatment
works in place by 2005.
There are limits on solids and on nutrients entering
watercourses. There are also limits on biochemical
oxygen demand (BOD)
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WWTP Aeration |
Relevant Regulations:
- Local Government (Water Pollution)
Acts 1977 and 1990.
- EU Directive 91/271/EEC.
- The Environmental Protection Agency
Act, 1992 (Urban Waste Water Treatment) Regulations,
1994 - SI 419 of 1994.
- Water Pollution Acts 1977 - 1990
- Section 4 licences where the treated
wastewater is discharged directly to the environment
- Section 16 licences permitting
raw effluent to be discharged to sewer for treatment
in, for example, a municipal wastewater treatment
plant.
Waste Hierarchy |
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