In this issue

 

Welcome

   - What’s to Come

 

 

QUDM 2017

   - Updates

 

 

Wrap Up

   - See you next month

 

 

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www.stormw.com.au 

 

 

Phone:

07 3398 4992

 

Welcome

Hello everyone and welcome to the August edition of “Keep Things Flowing”, the monthly newsletter presented by Storm Water Consulting.

This month the latest instalment of the Queensland Urban Drainage Manual was released. In this newsletter we bring you some of the important updates from the new manual. For any follow up information about these articles please respond to this email.

QUDM 2017

This month the Institute of Public Works Engineering Australia released the fourth edition of the Queensland Urban Drainage Manual (QUDM 2017). The Queensland Urban Drainage Manual addresses technical and regulatory requirements, provides details of appropriate design methods and computational procedures and covers both hydrologic and hydraulic procedures as well as environmental and legal elements.

So what are the major changes to the 2017 version of QUDM? I’m glad you asked. Some of the major changes to QUDM are presented below.

Background to QUDM

A partner document, “Background to QUDM”, has been created to assist with explanations and reasoning behind the technical and regulatory requirements made in QUDM. This document allowed QUDM to be condensed and focus on requirements rather than provide reasoning and justifications. At this time the “Background to QUDM” has not been made available.

Lawful Point of Discharge

The lawful point of discharge for a site was previously based on a two rule test:

1.     Stormwater must be discharged to land owned by the local authority;

2.     Discharging the stormwater must not create an adverse impact to neighbouring properties.  

The lawful point of discharge test has been modified as follows:

A.     If the proposed development does not alter the site’s stormwater discharge characteristics in a manner that may substantially damage a third party property, then no further steps are required to obtain tenure for a lawful point of discharge (providing that the previous circumstances were lawful).

If Item A listed above is not met, then the standard two rule test will still apply.  

Initial Basin Sizing

A simple method for estimating the required volume of detention storage has been provided in this edition of QUDM. The method involves calculating the effective reduction in the site’s initial loss capabilities. When a site becomes more impervious, less rainfall can be absorbed by the ground, leading to increased runoff from the site. QUDM recommends initial loss values representative of different ground conditions. Whilst this method is useful for planning a development, detailed hydrologic modelling is recommended for the actual design of detention basins. 

 

Wrap Up

We hope you enjoyed this edition of Keep Things Flowing. Feedback on articles presented is always welcomed and for further information on any of the articles presented please don’t hesitate to contact our office.

As always, Keep Things Flowing!

The Storm Team