Washington On Site Sewage Association

Founded in 1990, the Washington On-Site Sewage Association is a non-profit trade association serving the on-site wastewater industry. Today the organization has grown to encompass all disciplines of the industry, has continued to expand its impact, and supports improvement in all of the industry's professions. These professional areas include regulators, designers, installers, operations and maintenance support, and manufacturers/suppliers operating in the state of Washington. WOSSA has since been a leading onsite professional membership association for the onsite septic industry with key consideration to the Consumer, Public Health and the Environment.