The Water Supply (Water Quality) (Scotland) Regulations 2001

Part IV

SCHEDULE 3 MONITORING

TABLE 1 PARAMETERS AND CIRCUMSTANCES FOR CHECK MONITORING

(1)	(2)	(3)
Item	Parameter	Circumstances
1.	Aluminium	– When used as flocculant or where the water originates from, or is influenced by, surface waters
2.	Ammonium
3.	Clostridium perfringens (including spores)	– Where the water originates from, or is influenced by, surface waters
4.	Coliform bacteria
5.	Colony counts
6.	Colour
7.	Conductivity
8.	Escherichia coli (E. Coli)
9.	Hydrogen ion
10.	Iron	– When used as flocculant or where the water originates from, or is influenced by, surface waters
11.	Manganese	– Where the water originates from, or is influenced by, surface waters
12.	Nitrate	– When chloramination is practised
13.	Nitrite	– When chloramination is practised
14.	Odour
15.	Taste
16.	Turbidity

TABLE 2 ANNUAL SAMPLING FREQUENCIES: WATER SUPPLY ZONES

(1)	(2)	(3)	(4)
Substances and parameters subject to check monitoring	Estimated population of water supply zone	Reduced	Standard
Notes:
+ See regulation 6(2) and Table 1 in Schedule 3.
* Sampling for these parameters may be within water supply zones or at supply points as specified in Table 3, subject to notes (ii) and (iii) below.
(i) Where the population is not an exact multiple of 5000, the population figure should be rounded up to the nearest multiple of 5000.
(ii) Audit monitoring in water supply zones is required only where sodium hypochlorite is added after water has left the treatment works. In other circumstances, audit monitoring is required at supply points.
(iii) To monitor for total indicative dose (for radioactivity).
E.Coli	<100		4
Coliform bacteria Residual disinfectant	≥100		12 per 5000 population(i)
Aluminium*
Ammonium
Clostridium perfringes (including spores)*(i)
Colony counts	<100	1	2
Colour	100 – 4,999	2	4
Conductivity*	5,000 – 9,999	6	12
Hydrogen ion	10,000 – 29,999	12	24
Iron+	30,000 – 49,999	18	36
Manganese+	50,000 – 79,999	26	52
Nitrate+	80,000 – 100,000	38	76
Nitrite+
Odour
Taste
Turbidity
Parameters subject to audit monitoring
Antimony
Arsenic
Benzene*
Benzo(a)pyrene
Boron*
Bromate(ii)*
Cadmium
Chromium	<100		1
Copper	100 – 4,999		4
Cyanide*	5,000 – 100,000		8
1, 2 dichloroethane*
Enterococci
Flouride*
Lead
Mercury*
Nickel
Pesticides*
PAH
Selenium
Sodium
Trichloroethene/Tetrachloroethene*
Tetrachloromethane*	<100		1
THM	100 – 4,999		4
Chloride*	5,000 – 100,000		8
Sulphate*
Total Organic Carbon*
Tritium*
Gross alpha(iii)*
Gross beta(iii)*

TABLE 3 ANNUAL SAMPLING FREQUENCIES: SUPPLY POINTS

(1)	(2)	(3)	(4)	(5)
Item	Substances and parameters subject to check monitoring	Volume of water supplied m3/d	Reduced	Standard
Notes:
(i) Check monitoring is required only in respect of surface waters (see regulation 6(2) and Table 1 in Schedule 3), otherwise audit monitoring.
(ii) Audit monitoring at supply points is permitted only where sodium hypochlorite is not added after water has left the treatment works. In other circumstances, audit monitoring is required in water supply zones.
(iii) To monitor for total indicative dose (for radioactivity).
1.	Clostridium perfringens (including spores)(i)	<20		2
		20 – 999	2	4
2.	Conductivity	1,000 – 1,999	6	12
		2,000 – 5,999	12	24
		6,000 – 9,999	18	36
		10,000 – 15,999	26	52
		16,000 – 32,999	52	104
		33,000 – 49,999	78	156
		50,000 – 67,999	104	208
		68,000 – 84,999	130	260
		85,000 – 101,999	156	312
		102,000 – 119,999	183	365
		120,000 – 241,999	365	730
		242,000 – 484,999	730	1,460
		485,000 – 728,999	1,095	2,190
	Parameters subject to audit monitoring
3.	Benzene
4.	Boron
5.	Bromate(ii)
6.	Cyanide
7.	1,2 dichloroethane
8.	Fluoride	<20		1
9.	Mercury	20 – 999		4
10.	Pesticides	1,000 – 49,999		8
11.	Trichloroethene/Tetrachloroethene	50,000 – 89,999		12
		90,000 – 299,999		24
12.	Tetrachloromethane	300,000 – 649,999		36
13.	Chloride	≥650,000		48
14.	Sulphate
15.	Total organic carbon
16.	Tritium
17.	Gross alpha(iii)
18.	Gross beta(iii)

TABLE 4 ANNUAL SAMPLING FREQUENCIES: WATER TREATMENT WORKS

(1)	(2)	(3)	(4)	(5)
Item	Substances and parameters subject to check monitoring	Volume of water supplied m3/d	Reduced	Standard
Notes:
(i) check monitoring at treatment works is required only when chloramination is practised. In other circumstances, audit monitoring is required.
1.	E. coli	<20		4
2.	Coliform bacteria	20 – 1,999	12	52
3.	Colony counts	2,000 – 5,999	52	104
4.	Residual disinfectant	6,000 – 11,999	104	208
		≥12,000	104	365
5.	Nitrite(i)	<20		2
6.	Turbidity	20 – 999	2	4
		1,000 – 1,999	6	12
		2,000 – 5,999	12	24
		6,000 – 9,999	18	36
		10,000 – 15,999	26	52
		16,000 – 32,999	52	104
		33,000 – 49,999	78	156
		50,000 – 67,999	104	208
		68,000 – 84,999	130	260
		85,000 – 101,999	156	312
		102,000 – 119,999	183	365
		120,000 – 241,999	365	730
		242,000 – 484,999	730	1,460
		485,000 – 728,999	1,095	2,190
	Substances and parameters subject to audit monitoring
7.	Nitrite(i)	<20		1
		20 – 999		4
		1,000 – 49,999		8
		50,000 – 89,999		12
		90,000 – 299,999		24
		300,000 – 649,999		36
		>650,000		48