The Drinking Water Laboratory Appraisal Program in Iowa was initiated in the early 1940s. Public water supplies in Iowa are required to monitor their drinking water to determine if it is adequately protected from microbiological, chemical, and radiochemical contaminants. Laboratory certification is required for all laboratories conducting analyses of public water supplies for compliance with the Safe Drinking Water Act (SDWA).

With rule changes effective 2/11/2004, the IDNR has grouped the SDWA parameters into eight analytical groups for the purpose of certification. Analysis of all SDWA results must be reported electronically to the IDNR. See Reporting Results To IDNR for additional detail

SDWA laboratory certification in Iowa is performed in accordance with US EPA's manual, Manual for the Certification of Laboratories Analyzing Drinking Water: Criteria and Procedures, Quality Assurance, Fifth Edition, January 2005; available at http://www.epa.gov/safewater/labcert/index.html.

To be certified, a laboratory must pass an onsite evaluation of facilities, methods, and personnel staff and perform satisfactorily on an annual performance evaluation study. An onsite evaluation is conducted by UHL personnel for those laboratories located in Iowa. Reciprocal certification is possible for those laboratories located outside the state of Iowa if they are certified by an approved agency.