The Water Supply (Water Quality) (Scotland) Regulations 1990

Regulations 13 and 17

SCHEDULE 2 SAMPLING FREQUENCIES

TABLE 1:

Sampling frequencies at consumers' taps

Parameters	Water Supply Zone		Sampling Frequency (number per annum)
	Volume distributed (m3/d) for domestic purposes	Population Supplied	Reduced		Standard	Increased
			Ground water	Surface water
Conductivity or	≤100	≤500			4	12
hydrogen ion	101-1000	501-5000	4	4	6	12
Odour	1001-2000	5001-10000	4	6	12	24
(qualitative)	2001-4000	10001-20000	6	12	24
Taste	4001-7000	20001-35000	11	21	42
(qualitative)	7001-10000	35001-50000	15	30	60

TABLE 2:

Sampling frequencies at consumers' taps

Parameters	Water Supply Zone		Sampling Frequency (number per annum)
	Volume distributed (m3/d) for domestic purposes	Population Supplied	Reduced		Standard	Increased
			Ground water	Surface water
Odour
(quantitative)
Taste
(qualitative)
Turbidity	≤100	≤500			4	12
Temperature	101-1000	501-5000			4	12
Hydrogen ion	1001-2000	5001-10000			4	24
Nitrate	2001-4000	10001-20000	4	4	6	24
Nitrite	4001-7000	20001-35000	4	5	10	36
Ammonium	7001-10000	35001-50000	4	5	10	48
Ammonium
Iron
Aluminium
Manganese

TABLE 3:

Sampling frequencies at consumers' taps

Parameters	Water Supply Zone		Sampling Frequency (number per annum)
	Volume distributed (m3/d) for domestic purposes	Population Supplied	Reduced	Standard	Increased
Notes
(i) ie any fungicide, herbicide or insecticide; increased or reduced sampling, where required or permitted, may be confirmed to the substance in question.
(ii) The sum of the detected concentrations of fluoranthene, benzo 3.4 fluoranthene, benzo 11.12 fluoranthene, benzo 3.4 pyrene, benzo 1.12 perylene and indeno (1,2,3-cd) pyrene.
Trihalomethanes	≤7000	≤3500	1	4	12
Tetrachloromethane
Trichloroethene
Tetrachloroethene
Copper
Lead	7001-10000	35001-50000	1	4	24
Zinc
Pesticides(i)
Polycyclic aromatic hydrocarbons(ii)

TABLE 4:

Sampling frequencies at consumers' taps

Parameters	Sampling Frequency
	(number per annum)
	Standard	Increased
Chloride
Sulphate
Calcium
Magnesium
Sodium
Potassium
Dry residues
Oxidizability
(permanganate value)
Total organic carbon
Boron
Surfactants
Phosphorus	1	12
Fluoride
Barium
Silver
Arsenic
Cadmium
Cyanide
Chromium
Mercury
>Nickel
Antimony
Selenium
Total hardness
Alkalinity

TABLE 5:

Sampling frequencies at supplyh points

Water Supply Zone or Combination of Zones		Sampling Frequency (number per annum)
Volume distributed (m3/d) for domestic purposes	Population Supplied	Table 1* Parameters				Table 2* Parameters				Table 3* Parameters				Table 4* Parameters
		Reduced		Standard	Increased	Reduced		Standard	Increased	Reduced		Standard	Increased	Reduced		Standard	Increased
		GW	SW			GW	SW			GW	SW			GW	SW
GW = Ground water SW = Surface water
* Reference is to Tables 1 to 4 of this Schedule
≤100	≤500			4	12			4	12	1	2	4	12			1	12
101-1000	501-5000	4	4	6	12			4	12	1	2	4	12			1	12
1001-2000	5001-10000	4	6	12	24			4	24	1	2	4	12			1	12
2001-4000	10001-20000	6	12	24		4	4	6	24	1	2	4	12			1	12
4001-10000	20001-50000	15	30	60		4	5	10	60	1	2	4	12			1	12
1001-20000	50001-100000	30	60	120		5	10	20	60	2	3	6	24	1	1	2	24
20001-30000	100001-150000	45	90	180		8	15	30	60	2	3	6	24	1	2	3	24
30001-60000	150001-300000	90	180	360		15	30	60	120	2	3	6	24	2	3	6	24
60001-100000	300001-500000	90	180	360		30	60	120		3	5	10	24	3	5	10	24
100001-200000	500001-1000000	90	180	360		30	60	120		5	10	20	36	5	10	20	36

TABLE 6:

Sampling frequencies at consumers' taps

Parameters	Water Supply Zone		Sampling Frequency (number per annum)
	Volume distributed (m3/d) for domestic purposes	Population Supplied	Standard
Total Coliforms	≤100	≤500	12
Faecal coliforms	101-1000	501-5000	12
Residual disinfectant	1001-2000	5001-10000	24
Colony counts	2001-4000	10001-20000	48
		20001-50000	at the rate of 12 per 5000 population except in the case of colony counts where the standard number is 52

TABLE 7:

Sampling frequencies for treatment works

Parameters	Volume of water supplied (m3/d) for domestic purposes	Sampling frequency (number per annum)
		Reduced	Standard
1. Total and faecal coliforms,	≤2000	12	52
residual disinfectant and	2001-6000	52	104
colony counts
2. Total and faecal coliforms	6001-12000	104	208
and residual disinfectant	>12000	104	365
3. Colony counts	>6000	52	104