
1 
These Regulations may be cited as the Surface Waters (Classification) (Scotland) Regulations 1990 and shall come into force on 1st May 1990.
2 
These Regulations, and the system of classification prescribed by these Regulations, apply in relation to inland waters (including any loch or pond which, by virtue of an order made under section 30A(5)(b) of the Control of Pollution Act 1974, is to be treated as a relevant loch or pond).
3 
The waters to which these Regulations apply shall be classified DW1, DW2 or DW3, as the case may be, according to the criteria set out in the Schedule to these Regulations, which criteria shall determine their suitability for abstraction by water authorities within the meaning of the Water (Scotland) Act 1980 for supply (after treatment) as drinking water.
James Douglas-Hamilton
Parliamentary Under Secretary of State, Scottish Office
St. Andrew’s House,
Edinburgh
23rd January 1990
SCHEDULE
Regulation 3

The limits set out below are maxima

(1) (2)  (3) (4) (5)
No. in Annex II to 75/440/EEC Parameters  DW1 DW2 DW3
2 Coloration (after simple filtration) mg/1 Pt Scale 20 100 200
4 Temperature °C 25 25 25
7 Nitrates mg/1 NO3 50 50 50
8(1) Fluorides mg/1 F 1.5
10 Dissolved iron mg/1 Fe 0.3 2
12 Copper mg/1 Cu 0.05
13 Zinc mg/1 Zn 3 5 5
19 Arsenic mg/1 As 0.05 0.05 0.1
20 Cadmium mg/1 Cd 0.005 0.005 0.005
21 Total chromium mg/1 Cr 0.05 0.05 0.05
22 Lead mg/1 Pb 0.05 0.05 0.05
23 Selenium mg/1 Se 0.01 0.01 0.01
24 Mercury mg/1 Hg 0.001 0.001 0.001
25 Barium mg/1 Ba 0.1 1 1
26 Cyanide mg/1 Cn 0.05 0.05 0.05
27 Sulphates mg/1 SO4 250 250 250
31 Phenols (phenol index) paranitraniline 4 aminoantipyrine mg/1 C6H5OH 0.001 0.005 0.1
32 Dissolved or emulsified hydrocarbons (after extraction by petroleum ether) mg/1 0.05 0.2 1
33 Polycyclic aromatic hydrocarbons mg/1 0.0002 0.0002 0.001
34 Total pesticides (parathion, BHC, dieldrin) mg/1 0.001 0.0025 0.005
39 Ammonia mg/1 NH4  1.5 4
Note
(1) The value is an upper limit set in relation to the mean annual temperature (high and low).
