Cryptosporidium

Approval of membrane and other filtration systems for Cryptosporidium removal

The Water Supply (Water Quality) Regulations 2000 require water companies to carry out a risk assessment for Cryptosporidium for each of their water treatment works. Associated with the Regulations is the guidance on assessing the risk from Cryptosporidium in treated water supplies. Paragraph 2.2 provides an option to install treatment capable of continuously removing or retaining particles greater than 1-micron diameter as a means of complying with the Regulations.

DWI Information Letter 16/99 advised water companies of the Inspectorate's interpretation of the treatment capability necessary to avoid continuous monitoring for Cryptosporidium.

The Secretary of State and the National Assembly for Wales have approved a number of membranes and other filtration systems for drinking water treatment. A full listing of these products is given in the Secretary of State's List of Approved Products

The following products are considered by the Inspectorate to be capable of continuously removing or retaining particles greater than 1-micron diameter:

The arrangements for applying to have products considered for inclusion in this list are given in Guidance on submissions of claims for removal of one micron particles.