Official UK information

Legislation

• The Water Supply (Water Quality) (Amendment) Regulations 1999 (SI 1999.1524)
  These regulations make specific provisions to ensure that water supplied for human consumption is not contaminated with cryptosporidium. They require water undertakers to carry out risk assessments to establish whether there is a significant risk from cryptosporidium oocysts in water supplied from their treatment works for human consumption (regulation 2(1)). Where it is established that there is such a risk the relevant water undertakers must use a process for treating the water to ensure that the average number of cryptosporidium oocysts per 10 litres of water is less than one. To verify compliance with this requirement water undertakers must ensure that the water leaving their treatment works is continuously sampled for cryptosporidium oocysts.
  
  
• The Water Supply (Water Quality) Regulations (Northern Ireland) 2007 (SR 2007. 147.);
  
  
• The Cryptosporidium (Scottish Water) Directions 2003;
  
  
• The Water Supply (Water Quality) Regulations 2000 (SI 2000/3184)
  Specific provisions to ensure that water supplied for human consumption in England and Wales by the licensed undertakers is not contaminated by Cryptosporidium is now contained in the Water Supply (Water Quality) Regulations 2000 (SI 2000/3184), as amended by the Water Supply (Water Quality)(Amendment) Regulations 2001 (SI 2001/2885) and the The Water Supply (Water Quality) Regulations 2000 (Amendment) Regulations 2007 (SI 2007/2734).
  
  The substantive regulations, which first took partial effect on 1 January 2001, require (rr.27-29) water undertakers to assess the risk of contamination of their sources of supply and, where such a risk is established, to put in place measures (invariably filtration) to contain that risk such that the average number of oocysts per 10 litres of water is less than one. To verify compliance with this treatment standard, water leaving treatment works is subject to a continuous sampling and analysis protocol. Breach of the standard is a criminal offence.
  
  
• The Water Industry Act 1991
  Under s.70 of this Act, it is an offence, subject to a "due diligence" defence, for a water undertaker to supply water unfit for human consumption.

Further information

• Information from the UK Health Protection Agency