Flood mitigation measures were investigated for eliminating flood
problems for the 1% annual exceedance probability flood for:
Greystanes Creek from Fox Hills Golf Course to Fitzwilliam Road,
Toongabbi e,
Pendle Hill Creek from the Great Western Highway to Fitzwilliam
Road, Toongabbie, and
The Confluence Area extending from Fitzwilliam Road, on both creeks,
to Toongabbie Creek, including the confluence of Greystanes Creek
with Pendle Hill Creek.
The capacities of all channels, bridges and culverts in the Study Area
were assessed and compared with the 1% flood estimate for existing
conditions and for conditions with the upstream retarding basins
completed. On the basis of the comparison those structures which were
inadequate.