“100-year design event” means the flood event calculated using the 24-hour rainfall that has a one percent chance of being equaled or exceeded in a period of one year.

Source. #1716, eff 2-20-81; ss by #2207, eff 12-13-82; ss by #2900, eff 11-7-84, EXPIRED 11-7-90 New. #5080, eff 2-22-91; ss by #6462-A, eff 2-21-97; ss by #8288, INTERIM, eff 2-21-05, EXPIRES: 8-20-05; ss by #8412, eff 8-20-05; ss by #10508, eff 1-22-14; ss by #13979, eff 5-24-24 (formerly Env-Wr 101.01) (see Revision Note at chapter heading for Env-Wr 100)