Nimbin Water Security

Hi Lois, apologies for not having the information available on this page. The Boil water alert has now been lifted (Nimbin Rural Line customer boil water alert remains). The water treatment concerns were addressed swiftly. Please see below statement.

The Boil Water Alert for the village of Nimbin has been lifted, effective immediately. 

This only applies to the Nimbin Urban Boil Water Alert, Nimbin Rural customers remains under an ongoing Boil Water Alert. For information about the Nimbin rural alert click here.

On Tuesday, 5 December Nimbin village was placed on a boil water alert due to problems with water treatment.

The problem has been rectified and NSW Health has supported Council lifting the boil water alert.

Hi Ava,

The existing water supply configuration in Nimbin essentially relies on flows from Mulgum Creek i.e. there isn’t any substantive ‘on creek storage’, like a dam. With this, the capacity to supply additional development is limited. If we were to ramp up the extraction from the creek on an ongoing basis (to supply additional development), it would have widespread environmental impacts due to a reduced amount of water running down the creek. 

It’s important to understand that no water supply is ‘drought proof’. They are generally designed/configured under the ‘NSW Security of Supply Basis’, ( commonly referred to as the ‘5/10/20 rule’) so that:

1. Duration of water restrictions does not exceed 5% of the time; and
2. Frequency of restrictions does not exceed 10% of years ( i.e. 1 year in 10 on average); and
3. Severity of restrictions does not exceed 20%. Systems must be able to meet 80% of the unrestricted water demand (i.e. 20% average reduction in consumption due to water restrictions) through a repetition of the worst recorded drought, commencing with the storage drawn down to the level at which restrictions need to be imposed to satisfy a) and b) above.

Furthermore, under the drought management plan for the Nimbin Water Supply, there is a point at which the bulk fill point will be closed. This means that bulk water for rainwater tanks will need to be sourced from another catchment.

Thanks, 

Aaron

The plan in place prior to the flood event (to build a treatment plant at Nimbin) will improve water security and mitigate the risk of residents being completely cut of from supply (which occurred during the February 2022 flood).

 Aside from this, Council is investigating the suitability of an existing groundwater bore for use in the water supply. If suitable, this bore may be used during drought situations, or form part of the permeant supply mix.

The weir at Mulgum Creek essentially creates a permeant deep spot so that water can be harvested for consumption by the village. The weir itself is constantly spilling (other than in extreme droughts), meaning that water is continuously flowing down the creek. Only a very small percentage of the water that flows down the creek makes its way in to the pipeline for ultimate consumption by the Nimbin residents.

Hi Robert, thank you for your questions.

The water treatment plant will require the use of chemicals as part of the process. The plant will be designed in accordance with relevant Australian Standards and to meet World Health Organisation (WHO) standards for drinking water.

The materials to be used in the reticulation system are manufactured to meet relevant Australian Standards and designed to withstand ground conditions where they are installed.

Suggestions about creating “water sinks” or “dams” or the like are not being considered at present as they are subject to rigorous, lengthy, expensive and somewhat onerous approval processes when compared to the other options available.

The impacts of climate change are being considered in regard to the calculation of the future availability of water supply for Nimbin.

The costs of construction of the new water treatment plant and associated water mains has already been factored into Council’s rates and charges for water. Review of these charges occurs each year as part of Council’s budget process.

Hi Jim, thank you for your questions.

Council has a program of monitoring to detect leaks in the water supply system. Any leaks that are found are dealt with as soon as possible.

In regard to residential users behaviour Council has had education programs in the past delivered by a Water Education Officer. That position is currently not filled and Council is reviewing its function and will make a decision on recruitment prior to the 2022/23 financial year. Rous Water also undertake region wide water conservation programs which includes Nimbin.

Council does not have specific data on what impact the measures adopted in the past have had on customer behaviour.

Council is not investigating any alternate water sources for Nimbin other than the licence from Mulgum Creek and groundwater sources (bore). Whilst not currently being considered, construction of a pipeline to connect to the Rocky Creek Dam supply is a further option that may be considered in the future.

Hi Yagia, thank you for your question.

Lismore City Council is not responsible for regulation of water flows, licences , environmental flows etc. in Mulgum Creek. That responsibility lies with the NSW Government and is regulated through the Department of Planning, Industry and Environment. Lismore City Council extracts water from Mulgum Creek in accordance with the terms of its Licence issued through that Department. The construction of the new water treatment plant and changes to the water reticulation network will mean that maintenance and operational practices can be improved such that less water is wasted during these practices, thus requiring less extraction from Mulgum Creek. This in turn means more water available for environmental flows.