Membership in the Water Design-Build Council is open to any private-sector company engaged in integrated design and construction services or construction management-at-risk (CMAR). A company must function in the capacity either as a prime contractor or under a risk-sharing arrangement with a partner. In providing these services, the company must have demonstrated in-depth, in-house comprehensive engineering capabilities to design and build public or private (investor-owned), rate-regulated utility water or wastewater treatment infrastructure facilities in North America.

WDBC Membership categories are regular and associate. Member categories are related to the gross revenues generated from design-build and CMAR water and wastewater infrastructure projects in North America in the prior calendar year. Revenue categories are based on those greater than $80 million, between $80 and $40 million, and those less than $40 million per year.

A full member is one whose firm is within the first two revenue categories. A full member has one representative member vote on the Board of Directors; and the official designated representative can be elected to serve as an officer of the Board of Directors. Firms within the third (revenue) category have the option of joining as an associate member.

All Associate members are entitled to a designated representative who attends all Board meetings and participates in all activities (committees and projects) of the Board. Associate Members have full voting privileges at the WDBC Annual Meeting and in committee activities, but do not have an official vote oat Board meetings. Accordingly, Associate Member representatives cannot be elected as an officer of the Board of Directors. All member firms are entitled to an alternative representative who also attends all meetings, and participates in committee and project activities.