(1) "Department" means the Washington state department of transportation, through its public transportation and rail division, or its successor.

(2) "Comprehensive transit plan" means the official document required of every county transportation authority pursuant to RCW 36.57.070 and of every public transportation benefit area pursuant to RCW 36.57A.060.

(3) "County transportation authority" means an entity created pursuant to chapter 36.57 RCW.

(4) "Population" means the number of residents as shown by the most recent population determination made by the office of financial management.

(5) "Public transportation benefit area" means an entity created pursuant to chapter 36.57A RCW.