prior to zoning revisions required by state planning laws adopted in comprehensive land use planning coordination act oregon and growth management act washington residential zoning in the suburbs set large minimum sizes for new subdivisions as late as the average minimum size for a new residential subdivision lot in the metro urban growth boundary outside the downtown portland area was ft ketcham et al a number of suburban cities in the region prohibited apartments instead of requiring a connected system of streets in new subdivisions cities allowed developers to establish culdesac communities that funnelled auto trips onto state highways residential development was haphazard and uncoordinated led by private developers rather than by public investment