American Rainwater Catchment Systems Association

The American Rainwater Catchment Systems Association (ARCSA), now operating as ARCSA International under The IAPMO Group, is a professional organization dedicated to promoting sustainable rainwater harvesting and stormwater management practices. Founded in 1994, the association provides education, resources, and standardized professional training for the industry. A central component of its work involves the development of codes and national standards, such as the ARCSA/ASPE/ANSI Standard 63, which establishes uniform requirements for the design, installation, and maintenance of rainwater catchment systems to ensure safety and performance.

ARCSA International serves a diverse membership of government professionals, academics, consultants, and equipment manufacturers by fostering a forum for knowledge exchange and industry advancement. To address gaps in system-level verification, the organization launched an in-field certification program that evaluates installed systems against established standards. This initiative provides independent confirmation of operational performance, helping regulators, engineers, and facility owners ensure that rainwater systems are safe, reliable, and compliant, ultimately supporting broader adoption of alternative water solutions.