Council’s updated Orange flood study is open for community comment

By July 25, 2019 News

Orange Mayor Reg Kidd is encouraging Orange residents to take a close look at a new updated flood study which was placed on public exhibition today.

Council and an independent consultant, Lyall & Associates, recently updated an earlier flood study of the city. The study identifies properties on maps of areas which could potentially be affected by flooding.

Orange City Council has sent letters to the owners of properties identified on the flood plain maps.

Orange Mayor Reg Kidd said it was a vital study, which would be used to plan future housing developments, gain government funding for projects to reduce the risk of floods and inform emergency services.

“The state government requires Council to complete a flood study every so often, and the last time Council did this was in 2009,” Cr Kidd said.

Flash flooding at the Bathurst Road/ Cox Avenue intersection

Flash flooding at the Bathurst Road/ Cox Avenue intersection on December 26, 2010. Photo By Cin Culverson

“Since then, Orange has grown quite a lot and it’s important we keep on top of the risk using the latest technology. This study identified the properties at risk,

with this knowledge we can now design and lobby for flood improvement measures, such as retention basins, to help reduce that risk.

“We did just that with information from the last study, and we were able to expand the East Orange channel.

“Over the years we’ve also built a network of stormwater management basins across the city to reduce the risk of flooding and to help control sediment flow into our waterways.

These include basins at Emus sportsground, one off McNeilly Avenue, Huntley Road, at Kinross Wolaroi School, in Valencia Drive, Kearney’s Drive and Clem Fawn Place and a recently completed one off William Maker Drive and Hawkes Lane to name a few.

While the previous study looked at ‘Riverine’ flooding, where floodwater overflowed from the banks of creeks, the new study also looks at ‘Overland’ flooding.

The maps of overland flooding describe areas that can be affected after very heavy storms, when water produced by heavy rain, that doesn’t come from a creek, flows from higher land in a neighbourhood, to lower land.

“For long term Orange residents this study, that shows where waterways can overflow their banks won’t be anything new. What’s new is that this latest study also looks at overland flow for the first time.

“The study of overland flooding attempts to analyse and raise awareness of flooding triggered by heavy storms in a neighbourhood.

“We are expecting some people may have questions and we’ll be working with residents to understand what the updated study may mean for them and their properties,” Cr Kidd said.

Autumn Street backyard flooded

A backyard in Autumn Street with flooding

Lyall & Associates started on the study about two years ago but compiled flood maps recently.

One of the initial steps taken was to survey residents of the existing known flooding areas and to collect historical information and community opinion regarding flooding in the city and drainage.

The consultant then used the latest technology to measure ground levels of every square metre of the city.

A plane was flown over the city and an infrared laser was used, called a LiDAR. The laser was used from the plane and was able to measure every change in level with an accuracy of up to 30mm.

Using this information, existing data and residents’ surveys, the consultant designed a series of maps detailing the probability of flooding in the Orange city from north Orange as far as Industry drive to east at the Northern Distributor Road, south including Shiralee and west to Dean Drive and Spencer Lane.

Cr Kidd said while the study documents are complex council wants to make it simple to find out more information.

“The flood study is open for public exhibition and comment and I encourage anyone who has concerns to jump online and look at Council’s YourSay Orange website. It has information about the study, frequently asked questions and you can pose your own questions or make a submission,” Cr Kidd said.

“We’re also hosting a community workshop on 1 August here anyone can come along and ask questions and learn more.

“The important thing to remember is the study only identifies properties already at risk of a flood.

“If residents have any concerns go to Council’s YourSay website for information or give Council a call on 6393 8000.” https://yoursay.orange.nsw.gov.au/flood-study-update

People playing in the flash flooding in Kite Street in 1966

Kite Street Orange – Flood by storm water from Cook Park – 23 Jan 1966 (CWD)(Orange and District Historical Society)

Leave a Reply