The Barton Creek Watershed Ordinance (BCWO) was passed in 1980 and represented a significant departure from the Lake Austin Watershed Ordinance. Key features of the ordinance included: impervious cover limits capped at 35 percent for commercial and multi-family development, and the use of density limits that varied with the location of the development. The BCWO did not require water control structures, nor did it provide a mechanism whereby an applicant could increase impervious cover using alternate methods. This ordinance relied entirely on non-structural water quality controls and introduced stream set back requirements that created five water quality zones with enumerated development restrictions for each one.