MCU14-0039 Flood report and flood man Plan rev August 2015

Como Glasshouse P/L C/‐ Martoo Consulting P/L
Flood Impact Assessment – 305 Lake McDonald Drive Cooroy


3.6              Flood Refuge
Given the widespread inundation of the site in moderate to severe flood events, including associated
water depths and flow velocities, the complete evacuation of the site is the preferred management
method. The depth of inundation across the site indicates that directing employees and persons to a
dedicated refuge area on the site would result in an unacceptable risk during flood events. As such, it
is recommended that employees and persons on site be evacuated to the nominated emergency
evacuation location illustrated in Appendix C. This location is located to above the 1% AEP flood event,
provides employees and persons on site with a safe emergency refuge point as well as the ability to
reach Lake MacDonald Road. Employees are to remain at the refuge site until it is deemed safe by the
relevant authorities and/or site manager to return to either the site or their homes.
Consideration has been made regarding developing a refuge area on site. This would take the form of
an area of land raised above the 1% AEP design event flood level. This poses two risks, namely:‐
1. Potential flood impacts caused by the placement of the refuge area in the floodplain; and
2. Potential risk to employees and persons on site should a flood event greater than a 1% AEP design
   event occur.
A refuge area on the site may prove beneficial during smaller events but should an event larger than
a 1% AEP design event occur, employees and persons on site will effectively be trapped and at risk of
rising floodwaters. As such, ensuring staff and persons are evacuated from the site as per the
procedures outlined below is considerably safer than remaining on an elevated pad within the
floodplain. Flood events typically occur very quickly in the vicinity of the site and the installation of a
water level gauge and the flood management procedures, outlined below, will provide site
management staff with adequate information regarding approaching flood events.
3.6.1            Procedures
Following are the procedures of the FMP. They are dependent on the conditions being experienced
at the time as well as the time of the day. There are three (3) general times of the day that will govern
the decision making process as follows: ‐
1.      Before Opening (i.e. does the site remain closed and are employees notified?);
2.      During normal Operation of the site; and
3.      After Closing (i.e. secure the premises and make safe in case of flood, notify employees about
        the following day).
Reference to these conditions and times will be made to facilitate the decision making process
discussed in each of the procedures.
Outside of opening hours
Outside of opening hours, the procedure for flood management is to notify employees to remain at
home and to not try and gain access to the site.
During opening hours
During opening hours and when employees and people are on site, the following procedures are to
be undertaken:‐
1.      Site manager to remain vigilant and to obtain information from the relevant authorities (see
        Table 3‐1) regarding the severity of rainfall.
2.      If localised flooding is imminent, the site manager is to observe the low‐level crossing to the
        south of the site (i.e. located just south of Location 1 as shown in Appendix C).
3.      If the low‐level crossing becomes inundated, the site manager is to: ‐


3917‐01 / R01 v02 ‐ 31/08/2015                                                                          12