New South Wales Consolidated Regulations

BLACKTOWN LOCAL ENVIRONMENTAL PLAN 1988 - REG 20

20 Development of land affected by the 1% annual exceedance probability flood

(1) In this clause:
"floodway" means the channel of a river or stream and those portions of land, affected by the 1% annual exceedance probability flood, adjoining the channel and which constitute the main flow path of floodwaters. Floodwaters are areas which, even if only partially blocked, would cause significant redistribution of the flood flow, which may in turn adversely affect other areas. They are often, but not necessarily, the areas of deeper flow or the areas where higher velocities occur.
"1% annual exceedance probability flood" means a flood which has a 1 in 100 chance of occurring in any one given year.

(2) Despite any other provision of this plan, the council may refuse consent to the carrying out of any development on land affected by the 1% annual exceedance probability flood where, in its opinion, the development may:

(a) adversely affect the efficiency, or unduly restrict the capacity, of the floodway or where the safety of the development would be affected in time of flood,

(b) affect the flood peak at any point upstream or downstream of the development,

(c) affect, to a substantial degree, the flow of floodwater on adjoining lands,

(d) cause avoidable erosion, siltation or unnecessary destruction of riverbank vegetation in the area,

(e) affect the water table on any adjoining land,

(f) adversely affect riverbank stability, or

(g) create a hazard to life or property in time of flood.