DWR (Dwr Cymru Welsh Water)

Report Data Range: For the whole year 2021

Table 1: Quality of water leaving service treatment works – European Standards

Parameter Name	Parameter Code	Prescribed Concentration or Value	Total Number of Tests	Tests Failed	1 Percentile (representing a minimum)	99 Percentile (representing a maximum)	No. of works with failures
Nitrite (Total)	A013B	0.1 mg NO2/l	508	0	<0.015	<0.015	0
Totals			508	0

Table 2: Quality of water leaving service treatment works – National Standards

Parameter Name	Parameter Code	Prescribed Concentration or Value	Total Number of Tests	Tests Failed	1 Percentile (representing a minimum)	99 Percentile (representing a maximum)	No. of works with failures
E coli (faecal coliforms Confirmed)	C002	0 number/100 ml	10,947	0	0	0	0
Total Coliforms (Confirmed)	C001	0 number/100 ml	10,947	5	0	0	5
Totals			21,894	5

Table 3: Quality of water leaving service treatment works – Additional Monitoring Requirements

Parameter Name	Parameter Code	Prescribed Concentration or Value	Total Number of Tests	Tests exceeding specification	1 Percentile (representing a minimum)	99 Percentile (representing a maximum)
Colony Counts After 3 Days At 22øc (Colony Counts)	C007	No abnormal change	10,921	N/A	0	2
Residual Disinfectant – Free	C009	No abnormal change	10,965	N/A	0.41	1.22
Residual Disinfectant – Total	C010	No abnormal change	10,964	N/A	0.46	1.31
Turbidity – Indicator	A002A	1 NTU	10,931	1	<0.3	<0.3
Totals			43,781	1

Table 4: Quality of water leaving service reservoirs – National Standards

Parameter Name	Parameter Code	Prescribed Concentration or Value	Total Number of Tests	Tests Failed	1 Percentile (representing a minimum)	99 Percentile (representing a maximum)	No. of reservoirs failing standard
E coli (faecal coliforms Confirmed)	C002	0 number/100 ml	16,778	1	0	0	1
Total Coliforms (Confirmed)	C001	0 number/100 ml	16,778	14	0	0	0
Totals:			33,556	15

Table 5: Quality of water leaving service reservoirs – Additional Monitoring Requirements

Parameter Name	Parameter Code	Prescribed Concentration or Value	Total Number of Tests	Tests exceeding specification	1 Percentile (representing a minimum)	99 Percentile (representing a maximum)
Colony Counts After 3 Days At 22øc (Colony Counts)	C007	No abnormal change	16,743	N/A	0	2
Residual Disinfectant – Free	C009	No abnormal change	16,810	N/A	0.24	0.93
Residual Disinfectant – Total	C010	No abnormal change	16,809	N/A	0.32	1
Totals:			50,362	0

Table 6: Quality of water leaving bulk supply points – European Standards

Parameter Name	Parameter Code	Prescribed Concentration or Value	Total Number of Tests	Tests Failed	1 Percentile (representing a minimum)	99 Percentile (representing a maximum)	No. of supply point with failures
1 2-Dichloroethane (Total)	F001	3 µg/l	218	0	<0.18	<0.18	0
Benzene (Total)	F002	1 µg/l	220	0	<0.097	<0.097	0
Boron	D005A	1 mg B/l	213	0	<0.014	<0.014	0
Bromate	F003	10 µg BrO3/l	65	0	<0.46	3.2	0
Cyanide (Total)	B003	50 µg CN/l	212	0	<3.6	<3.6	0
Fluoride (Total)	A027	1.5 mg F/l	214	0	<0.11	<0.11	0
Mercury (Total)	B005	1 µg Hg/l	213	0	<0.037	<0.037	0
Pesticides (Total by Calculation)	B010	0.5 µg/l	218	0	0	0.05086	0
Pesticides 2 4-D	P020	0.1 µg/l	212	0	<0.0078	0.008661	0
Pesticides 2 4-DB	P082	0.1 µg/l	8	0	<0.014	<0.014	0
Pesticides Aldrin	P002	0.1 µg/l	214	0	<0.0065	<0.0065	0
Pesticides Asulam	P133	0.1 µg/l	214	0	<0.011	<0.011	0
Pesticides Clopyralid	P018	0.1 µg/l	8	0	<0.0079	0.032	0
Pesticides Diazinon	P024	0.1 µg/l	37	0	<0.015	<0.015	0
Pesticides Dicamba	P025	0.1 µg/l	8	0	<0.023	<0.023	0
Pesticides Dieldrin	P028	0.03 µg/l	214	0	<0.007	<0.007	0
Pesticides Glyphosate	P042	0.1 µg/l	214	0	<0.0064	<0.00776	0
Pesticides Heptachlor	P043	0.03 µg/l	214	0	<0.0081	<0.0081	0
Pesticides Heptachlor Epoxide – Total (Trans, CIS) (Heptachlor Epoxide)	P044	0.03 µg/l	214	0	<0.0057	<0.0057	0
Pesticides Linuron	P051	0.1 µg/l	8	0	<0.012	<0.012	0
Pesticides MCPA 4-chloro-o-tolyloxyacetic acid	P054	0.1 µg/l	214	0	<0.011	<0.011	0
Pesticides MCPP (Mecoprop)	P053	0.1 µg/l	213	0	<0.0087	<0.0087	0
Pesticides Metaldehyde	P226	0.1 µg/l	8	0	<0.008	<0.008	0
Pesticides Metamitron	P194	0.1 µg/l	9	0	<0.014	<0.014	0
Pesticides Propetamphos	P069	0.1 µg/l	1	0	<0.015	<0.015	0
Pesticides Propyzamide	P071	0.1 µg/l	8	0	<0.012	<0.012	0
Pesticides Quinmerac	P224	0.1 µg/l	8	0	<0.006	<0.016	0
Pesticides Triclopyr	P131	0.1 µg/l	27	0	<0.012	<0.012	0
Radon	F031	100 Bq/l	4	0	0.7	1.2	0
Trichloroethene & Tetrachloroethene – Sum Of 2 Substances (Total by Calculation)	D009B	10 µg/l	218	0	0	0.1701	0
Totals			3,848	0

Table 7: Quality of water leaving bulk supply points – National Standards

Parameter Name	Parameter Code	Prescribed Concentration or Value	Total Number of Tests	Tests Failed	1 Percentile (representing a minimum)	99 Percentile (representing a maximum)	No. of supply points with failures
Tetrachloromethane (Total)	D008	3 µg/l	212	0	<0.21	<0.21	0
Totals			212	0

Table 8: Quality of water leaving bulk supply points – Additional Monitoring Requirements

Parameter Name	Parameter Code	Prescribed Concentration or Value	Total Number of Tests	Tests exceeding specification	1 percentile (representing a minimum)	99 percentile (representing a maximum)
Chloride	D002A	250 mg Cl/l	214	0	10.1	29
Clostridium Perfringens (Sulphite-reducing Clostridia) (Confirmed)	C004A	0 number/100 ml	517	0	0	0
Sulphate	A007	250 mg SO4/l	214	0	<8.9	59.95
Total Organic Carbon	A017	No abnormal change	214	N/A	<0.57	1.97
Tritium	F006	100 Bq/l	8	0	<3	<3
Totals			1,167	0

Table 9: Quality of water at consumer’s tap (zones) – European Standards

Parameter Name	Parameter Code	Prescribed Concentration or Value	Total Number of Tests	Tests Failed	1 Percentile (representing a minimum)	99 Percentile (representing a maximum)	No. of zones failing standard
1 2-Dichloroethane (Total)	F001	3 µg/l	448	0	<0.18	<0.18	0
Antimony	B008A	5 µg Sb/l	645	0	<0.083	0.12	0
Arsenic (Total)	B001A	10 µg As/l	645	0	<0.43	0.6616	0
Benzene (Total)	F002	1 µg/l	454	0	<0.097	<0.097	0
Benzo[a]Pyrene (Total)	D007	0.01 µg/l	649	0	<0.0013	<0.0013	0
Boron	D005A	1 mg B/l	426	0	<0.14	<0.14	0
Bromate	F003	10 µg BrO3/l	581	0	<0.46	1.854	0
Cadmium (Total)	B002	5 µg Cd/l	645	0	<0.062	<0.062	0
Chromium (Total)	B004	50 µg Cr/l	645	0	<0.18	0.33	0
Copper (Total)	A024A	2 mg Cu/l	649	0	<0.22	0.445	0
Cyanide (Total)	B003	50 µg CN/l	442	0	<3.6	<3.6	0
E coli (faecal coliforms Confirmed)	C002	0 number/100 ml	8,195	1	0	0	0
Enterococci (Confirmed)	C003	0 number/100 ml	650	0	0	0	0
Fluoride (Total)	A027	1.5 mg F/l	428	0	<0.11	<0.11	0
Lead (10 – will apply 25.12.2013)	B007B	10 µg Pb/l	649	0	<0.16	3.05	0
Mercury (Total)	B005	1 µg Hg/l	435	0	<0.037	<0.037	0
Nickel (Total)	B006A	20 µg Ni/l	649	1	<1.2	7.5	1
Nitrate (Total)	A012	50 mg NO3/l	646	0	<2.213	<16.3762	0
Nitrite – Consumer’s Taps	A013A	0.5 mg NO2/l	646	0	<0.015	<0.015	0
Nitrite/Nitrate formula	A013C	1 mg/l	646	0	<0.05	<0.33	0
Pesticides (Total by Calculation)	B010	0.5 µg/l	556	0	0	0.024	0
Pesticides 2 4-D	P020	0.1 µg/l	524	0	<0.0078	0.01775	0
Pesticides Aldrin	P002	0.03 µg/l	525	0	<0.0065	<0.0065	0
Pesticides Asulam	P133	0.1 µg/l	521	0	<0.011	<0.011	0
Pesticides Clopyralid	P018	0.1 µg/l	41	0	<0.0079	0.016	0
Pesticides Diazinon	P024	0.1 µg/l	33	0	<0.015	<0.015	0
Pesticides Dicamba	P025	0.1 µg/l	25	0	<0.023	<0.023	0
Pesticides Dieldrin	P028	0.03 µg/l	525	0	<0.007	<0.007	0
Pesticides Glyphosate	P042	0.1 µg/l	530	0	<0.0064	<0.0064	0
Pesticides Heptachlor	P043	0.03 µg/l	524	0	<0.0081	<0.0081	0
Pesticides Heptachlor Epoxide – Total (Trans, CIS) (Heptachlor Epoxide)	P044	0.03 µg/l	524	0	<0.0057	<0.0057	0
Pesticides Ioxynil	P049	0.1 µg/l	16	0	<0.0069	<0.0069	0
Pesticides MCPA 4-chloro-o-tolyloxyacetic acid	P054	0.1 µg/l	522	0	<0.011	<0.01177	0
Pesticides MCPP (Mecoprop)	P053	0.1 µg/l	520	0	<0.0087	<0.0087	0
Pesticides Metaldehyde	P226	0.1 µg/l	185	0	<0.008	<0.008	0
Pesticides Propyzamide	P071	0.1 µg/l	8	0	<0.012	<0.012	0
Pesticides Quinmerac	P244	0.1 µg/l	8	0	<0.006	<0.006	0
Pesticides Triclopyr	P131	0.1 µg/l	33	0	<0.012	<0.012	0
Polycyclic Aromatic Hydrocarbons (Total by Calculation)	B011F	0.1 µg/l	651	0	0	0	0
Selenium (Total)	B009	10 µg Se/l	645	0	<0.22	0.3854	0
Trichloroethene & Tetrachloroethene – Sum Of 2 Substances (Total by Calculation)	D009B	10 µg/l	447	0	0	0	0
Trihalomethanes (Total by Calculation)	D011	100 µg/l	650	0	3	63.56	0
Totals			27,196	2

Table 10: Quality of water at consumer’s tap (zones) – National Standards

Parameter Name	Parameter Code	Prescribed Concentration or Value	Total Number of Tests	Tests Failed	1 percentile (representing a minimum)	99 percentile (representing a maximum)	No. of zones failing standard
Aluminium (Total)	A021	200 µg Al/l	3,047	0	<44	47	0
Colour	A001	20 mg/l Pt/Co	3,052	0	<0.4	4.247	0
Iron (Total)	A022	200 µg Fe/l	3,048	7	<34	120	7
Manganese (Total)	A023	50 µg Mn/l	3,047	2	<7.1	9.904	2
Odour	A003	0 Dilution number at 25°C	3,055	5	0	0	4
Sodium (Total)	A009	200 mg Na/l	645	0	2.646	39.54	0
Taste (Taste Quant)	A004	0 Dilution number at 25°C	3,041	2	0	0	1
Tetrachloromethane (Total)	D008	3 µg/l	434	0	<0.21	<0.21	0
Turbidity	A002	4 NTU	3,051	0	<0.24	<0.3	0
Totals			22,420	16

Table 11: Quality of water at consumer’s tap (zones) – Additional Monitoring Requirements

Parameter Name	Parameter Code	Prescribed Concentration or Value	Total Number of Tests	Tests exceeding specification	1 percentile (representing a minimum)	99 percentile (representing a maximum)
Ammonium (Total)	A014	0.5 mg NH4/l	647	0	<0.01	<0.01
Chloride	D002A	250 mg Cl/l	436	0	<10.1	36.63
Coliform Bacteria (Indicator)	C001A	0 number/100 ml	8,195	9	0	0
Colony Counts After 3 Days At 22øc (Colony Counts)	C007	No abnormal change	3,041	N/A	0	7
Conductivity (Electrical Conductivity)	D001	2500 µS/cm at 20°C	3,053	0	66	460
Hydrogen ion (pH) – Indicator (Hydrogen ion) (pH)	A006	6.5 – 9.5 pH Value	3,048	0	7.3	8.4
Residual Disinfectant – Free	C009	No abnormal change	8,213	N/A	0.06	1.01
Residual Disinfectant – Total	C010	No abnormal change	8,213	N/A	0.16	1.08
Sulphate	A007	250 mg SO4/l	436	0	<8.9	62
Total Organic Carbon	A017	No abnormal change	427	N/A	<0.57	2.172
Totals			35,709	9