The Creighton Report

Wagga Wagga Report
The original application was subject to extensive flood reporting and assessment to
determine the impacts associated with the proposed development. The conclusion of the
original assessments as reported to the Joint Regional Planning Panel was as follows: 159
The findings of the flood impact assessment shows that the proposed development is
compatible with the flood hazard of the land and will not significantly affect flood behaviour.
As a condition of consent it will be necessary for the applicants to prepare a flood evacuation
and management plan and that will incorporate measures to manage risk to life from flood.
The minor flood impacts are unlikely to have any significant adverse impact on the
environment or cause avoidable erosion, siltation, destruction of riparian vegetation or a
reduction in the stability of river banks or watercourses in the area. The area is already flood
prone and the risk of flood to the surrounding community is well known, the introduction of
this major recreation facility is not likely to result in unsustainable costs to the community as
a result of flooding.
Flooding is a natural phenomenon and whilst models are the most effective way of predicting
levels and impacts they remain an educated prediction. The flood will never behave exactly
in accordance with a model and therefore a degree of inaccuracy and variation should be
expected, accordingly current practice accepts that a flood impact of less than or equal to
0.02m can be assumed as negligible and in most cases accepted as model height variances.
The proposed development will be a valuable resource to the local economy and to the
regional harness racing industry. The impacts of flooding on this investment are clear and
the proposed mitigation in terms of raising key features of the development are considered
to be appropriate and acceptable in this case.
It was a condition of the consent (issued November 2015) that HRNSW, as the applicant of
the development, obtain the necessary flood work approval from Water NSW. HRNSW
engaged WMA Water to complete the required additional assessment which was completed
in August 2017. This was over two years since the original plans were prepared and
amendments to the layout of the clubhouse and surrounds had already commenced by the
applicants. The plans that were used by WMA Water to prepare the report of August 2017
were therefore those that are currently the subject of this modification. Whilst these plans
were not the approved plans (emphasis added), at the time they were the plans used for the
flood modelling and therefore the report provided (dated August 2017) in support of the
modification application was considered appropriate and acceptable. 160
The additional report was required to review the impacts on local catchment flooding not just
riverine flooding. The report was also to be based on the current levee height not the
completed raised levee as the original reports had been.
As noted, the modelling was based on the plans that are now included as a modification
application and included a solid colourbond steel fence to the track (excluding the southern
spectator and access area) of 1.2 metres in height that is designed to block water other than
for a 0.1 metre gap at the base of the fence. The assessment found that the solid boundary
fence would not significantly alter flood impacts.
In terms of riverine flooding, the findings of the report conclude that the modified layout
results in the same outcome as originally reported, that is that the flood impacts are no
159
Ibid pp 20-2.
160
Ibid.
39