Environmental:

EU Water Framework Directive:
http://europa.eu.int/comm/environment/water/water-framework/index_en.html

Irish Environmental Protection Agency:
http://www.epa.ie/

UK Drinking Water Inspectorate:
http://www.dwi.gov.uk/

Environment Agency for England & Wales:
http://www.environment-agency.gov.uk/

Environment Agency for Scotland:
http://www.sepa.org.uk

United States Environmental Protection Agency (US EPA):
http://www.epa.gov/

WRC(Water Research Council):
http://www.wrcplc.co.uk/index.asp

Aquacheck – Water analysis Proficiency Testing scheme. One of the biggest and best established PTs in the world:
http://www.aquacheck.net/

European Commision Eco-Management and Audit Scheme:
http://europa.eu.int/comm/environment/emas/index_en.htm

ISO 14001 website, including information on implementing the Standard, tools and links:
http://www.iso14000.com/

The EcoGateway: Links and directories on all aspects of eco-management. Mainly USA-based links; but many of international interest:
http://www.ecoiq.com/onlineresources/index.html

Environmental Data Services (ENDS) - Environmental News & Directories:
http://www.ends.co.uk