Working together for a flood-resilient Newstead
Newstead has a history of flooding. Most recently, the town experienced flood events in 2000, 2010, 2011, 2016 and 2022. Therefore, Council is working with Water Technology to carry out a flood study and develop a flood mitigation strategy for Newstead and provide property saving solutions.
Newstead does have an earthen levee that protects against flooding events similar to the size of the 2022 flood, however the characteristics of the levee are unknown, and no formal management arrangement of the levee exists. Future floods are predicted to be more severe, associated with increased rainfall intensities. This may lead to more frequent floods that could breach the existing levee.
Water Technology have simplified the potential solutions and presented them below as three mitigation options. These are listed below, and we are now seeking community input on the prioritisation of these options.
You can get involved by:
- Reading the material on this page and submitting a response via the form below by August 8
- Attending the community information session in Newstead on July 28
- Reaching out to the contact listed on this page.
Provide your feedback on the flood mitigation options by August 8
As part of the Newstead Flood Study Council and stakeholders have developed three mitigation options as outlined below, with the objective of managing future flooding in Newstead. Please read them carefully and provide your feedback at the bottom of the page.
What is 1% Annual Exceedance Probability (AEP)?
Annual Exceedance Probability (measured as a percentage) is a term used to describe the magnitude (size) of a flood. It is a way of describing the probability of a flood of a particular size being equalled or exceeded in any given year. For example, a 1% AEP flood is a flood that has a 1% chance of occurring in any one year.
Mitigation option A: Vegetation removal
The below option shows what would happen if vegetation was removed in the Loddon River channel at and downstream of the Pyrenees highway bridge to allow water to drain away form the town more quickly.
Modelling outcome:
- Reduce the flood level by up to 150 mm inside the levee
- Reduces the flood level up to 300 mm outside the levee, but does not reduce the flood extent
- Three less properties flooded above the floor
Click maps to enlarge
Mitigation option B: Raising the Newstead levee
The below option shows what would happen if the existing levee alignment was raised but not extended.
Modelling outcome:
- Reduces the flood level by up to 1.4 m
- Reduces the flood extent by up to 100 m inside the levee
- Increases flood levels outside the levee by up to 300 mm
- The reduction in flood level will result in 35 less properties flooded above floor
Click maps to enlarge
Mitigation option C: Raising and extending the levee
The below option shows what would happen if existing levee is raised and extended. This option removes the flood extent inside the levee, while increasing flood levels outside the levee by up to 300 mm.
Modelling outcome:
- Increase the flood levels outside the levee by up to 300 mm
- The reduction in flood level and extent results in 88 less properties flooded above floor
Click maps to enlarge
