Approved Document OPW21-0278

                                                                Ref No 20648-R1 – Rev 2



We initially assessed the catchment for the access culvert as 1.27 Ha as per the
marked-up aerial below, however on closer inspection of the site we discovered that
the property two doors to the south contained a landscaped mound that diverted
overland flows from this property to the south instead of towards the subject property,
substantially reducing the catchment directed to the new access.




Following completion of the house construction the owners also installed a
landscaped berm along their boundary to the west of the house site to help divert
overland flows away from the house and into the open drain. The revised catchment
area for the access culvert is shown below.




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