50 CFR §600.210

1. (a)Voting members (other than principal state officials, the Regional Administrators, or their designees) are appointed for a term of 3 years and, except as discussed in paragraphs (b) and (c) of this section, may be reappointed. A voting member's Council service of 18 months or more during a term of office will be counted as service for the entire 3-year term.
2. (b)The anniversary date for measuring terms of membership is August 11. The Secretary may designate a term of appointment shorter than 3 years, if necessary, to provide for balanced expiration of terms of office. Members may not serve more than three consecutive terms.
3. (c)A member who has completed three consecutive terms will be eligible for appointment to another term one full year after completion of the third consecutive term.