Showing posts with label drinking water. Show all posts
Showing posts with label drinking water. Show all posts

Friday, 10 March 2023

When Clarence Valley Council tries to ignore the elephant in the room and local media with the best of intentions doesn't even see that enormous pachyderm


For reasons best known to itself, Clarence Valley Council administration has not publicly dotted the "i"s and crossed the "t"s for elected councillors and the Clarence Valley resident population when it comes to root causes of increased water turbidity and poor quality drinking water.


It's all about dirt. The deep soils and topsoils which cover and strengthen the rocks which hold Clarence River Basin mountains, hills and slopes in place; soils which are building blocks for both vegetation & biodiversity growth; soils which allow arable farming on valley floors big and small - including on the identified Clarence River floodplain.


The connection between clear-felled land, disturbed soils caused by mining, state-owned & private forestry, land laid bare by largescale wildfires, sloping land eroded by rain bombs, river banks scoured by record flooding, waterways thick with suspended soil particles and, a decline in water quality, is there for all to see. 


As is the poor stewardship of the NSW Government - which is supposed to ensure healthy waterways - but whose actions in allowing inappropriate levels of native vegetation removal, poorly monitoring mining exploration activity and its own continuous native timber forestry in sensitive catchments & sub-catchments is contributing to turbidity issues in north-east New South Wales.


It appear that absolutely no-one in the Perrottet Coalition Government is looking to address the root cause of water turbidity and erratic urban water quality. 


There appears to be a political blindness in 2023 to the following:


(i) the 2019-20 megafires started a process of exposing soils over wide areas of what had been closed and open forests in the Northern Rivers region;


 (ii) the further clearing of some of those fire grounds for retrievable native timber exacerbated this process; 


(iii) in 2022-23 the sensitivity and environmental risk associated with these forests is recognised as a continuing issue by the NSW Environmental Protection Agency - especially in areas where commercial native timber forestry is still occurring;


(iv) the 2022 extreme flooding increased the rate at which destabilised and/or degraded soils, particularly the exposed dispersive soils which create high levels of turbidity, made their way into streams, creeks, rivers and major waterways; and


(v) riverine landscapes do not have an infinite ability to withstand population pressure coupled with an increase in the frequency of natural or climate-induced disasters. The resilience Clarence River Basin waterways have demonstrated in the past does not guarantee their future capacity to experience recurrent disturbances while retaining essential function, structures and feedbacks.


A filtration plant may be advisable for urban water supplies, but it won't keep Clarence Valley waterways healthy, alive with biodiverse aquatic ecosystems and productive.


Ecotourism, water-based activity tourism and freshwater recreational fishing tourism, as well as the lucrative local wild-caught prawn industry, depend on healthy rivers. Rivers that are not just healthy but that can be seen to be healthy.



Examples of river and creek turbidity in the Clarence River catchment, 2022. 
IMAGES: The Daily Telegraph (top) Clarence Environment Centre (bottom) 



Clarence Valley Independent, 1 March 2023:


Future filtration for Valley water


Filtration of the Clarence Valley’s drinking water supply is again back on the agenda following this months Level Four severe water restrictions which lasted 11 days.


The Rushforth Road Water Treatment Plant RRWTP masterplan, which aims to replace the existing reservoir without impacting future construction of a filtration plant, is on the agenda at the February 28 Clarence Valley Council CVC meeting.


Prepared for council by consultant Beca H2O, the masterplan includes the replacement of the existing 32 megalitre reservoir, which is included in CVC’s 2022/2023 Operational Plan, and for future construction of filtration.


It is recommended that Council progress the Masterplan by commencing the planning approval process for a future filtration plant at Rushforth Road Water Treatment Plant,” council papers state.


Council staff recommend councillors note the masterplan and commence the planning approval process for future construction of a filtration plant by calling open tenders to undertake an Environmental Impact Statement.


CVC first adopted a Drinking Water Management System DWMS at its August 19, 2014 meeting and an updated DWMS was adopted at the May 2020 meeting.


Up until the 1990s, drinking water was extracted regardless of turbidity, then in the early 1990s selective extraction was introduced to improve water quality when turbidity was below 10 Nephelometric Turbidity Units (NTU).


Councils 2014 DWMS saw the turbidity level drop to 5 NTU, then the May 2020 DWMS further dropped the turbidity level to 3.5 NTU.


Currently, CVC water supplies are disinfected at Rushforth Road “by chloramination (adding ammonia to chlorine) as this provides the most stable disinfectant in lengthy pipeline systems because chloramines decay at a lower rate than free chlorine,” council papers state.


Tenders have been called for stage one of the masterplan which will see a 1.5 ML Chlorine Contact Tank and a 16ML Treated Water Storage Tank installed at the RRWTP, estimated to cost $14.7 million in October 2021.


The provision of a Chlorine Contact Tank will allow the primary disinfection at Rushforth Road by free chlorination while, by adding ammonia after the contact tank, continue to provide for a chloramine residual in the lengthy pipeline network,” council papers state.


Stage two of the masterplan is the conceptual design for filtration to be constructed at the RRWTP and is estimated to cost $63.8 million, with an annual operating cost of $2.1 million.


The Masterplan has confirmed that gravity flow through the plant is feasible, and all elements of the plant have been conceptually located so that the current plant (with the addition of the chlorine contact tank) can continue to operate during construction,” council papers state.


Due to its construction cost the filtration plant is classified as State Significant Development, and therefore needs planning approval via an Environmental Impact Statement (EIS).


It is recommended that Council commence the approval process for a future filtration plant by calling tenders to undertake an EIS.”


The last time council considered filtration at its April 15, 2014 meeting it was estimated the construction and operation of a filtration plant would add $275 annually to the typical residential bill.


The drinking water risk is not assessed by the State Government as being high enough for funding assistance under the current Safe and Secure Water Program,” council papers state.


The Rushforth Road water treatment has been allocated a risk score of “4”, while the program funding is currently only sufficient to provide assistance for projects with a risk score of “5”.”


Due to this situation, it is likely that CVC will require loans to fund the water filtration project.

 

Wednesday, 23 June 2021

Two days remaining to comment on Clarence Valley Council's "Draft Water Restriction Policy - Version 5"


Clarence Valley Council - On Exhibition


Water Restrictions V5 (draft)

Outlines the triggers that we use to introduce or revoke water restrictions.


Purpose


To introduce or revoke water restrictions on the use of reticulated water in the Clarence Valley as required in accordance with the triggers nominated in the procedures and in compliance with relevant Acts.


This policy applies to all properties using water supplied by Council’s water supply infrastructure. The policy does not apply to the use of water from sources that are not part of Council’s water supply infrastructure such as farm dams, watercourses, bores, and rainwater tanks on properties that have no connection to Council’s water supply.


The Draft Water Restrictions policy is available here.


Council welcomes submissions to this policy. Submit online by 11:00 pm on Friday 25 June 2021 by clicking on the Make a Submission button below.



https://www.clarence.nsw.gov.au/cp_themes/metro/make-a-submission.asp






Alternatively, comments can be made in writing to the General Manager, Clarence Valley Council, Locked Bag 23, Grafton, NSW 2460 and clearly marked “Draft Water Restrictions Policy".


For further information about the draft policy, please contact Chris Hellyer, Environmental Officer, Education; Water Efficiency < Christopher.Hellyer@clarence.nsw.gov.au >.


NOTE: A major change in Water Restrictions V5 is that the trigger for imposition of Level 1,2, 3 & 4 water restrictions will no longer be the volume of water remaining in the Shannon Creek Dam, but the combined water volume in Shannon Creek and Karangi dams. This in effect will allow water extraction (without accompanying Level 1 water use restrictions) to continue after Shannon Creek Dam water levels have fallen below the current trigger point of 80% of this dam's water storage capacity.


On 17 June 2021 Shannon Creek Dam was 84% full and Karangi Dam was 99.2% full. This means that Permanent Water Conservation Measures are in place for the Clarence Valley -  the use of sprinklers and unattended hoses is banned permanently between the hours of 9am and 4pm every day when evaporation is at its highest. However, there are no restrictions on handheld hoses or micro-sprays and drippers/sub-surface irrigation.


Given that Coffs Harbour City LGA contributes little to water storage in Karangi Dam (water supplied by Orara & Nymboida Rivers & Shannon Creek Dam) and nothing to storage in the Shannon Creek Dam (water supplied by Nymboida River) and, with no backfeed to Clarence Valley LGA according to Karangi Dam's daily data, it will be the higher water use of Coffs Harbour, with an est. resident population 33 per cent larger than Clarence Valley's population, which will all but guarantee that a return to Level 1 restrictions will likely occur before Spring arrives - even though the entire north-east region of NSW is now drought free and expecting more rain.


However it is not just the size of Coffs Harbor City's population which makes its water extraction levels potentially problematic. It's the fact that the resident population does not live in the Clarence River catchment area which leads to widespread misunderstanding of: (i) the boundaries of the actual catchment area; (ii) the highly variable nature of rivers within the system; the actual volume of freshwater flows; and (iii) the point at which the 394km long Clarence River itself - from its rising near Rivertree to its emptying into the sea at the tidal estuary mouth - starts to become saline and increasingly unfit for human and animal consumption as well as unfit to use for irrigation. That point is approximately at the end of the first 286km of its journey to the ocean. The combined average annual flow from the freshwater tributaries as this flow enters the Clarence River tidal pool appears to be in the vicinity of 3,072,884ML, which is perhaps a better indicator than the annual water exchange that occurs between the ocean and the estuary.


Clarence Valley residents will recognise these basic misunderstandings in this quote on Coffs Harbour City Council's website:


Regardless of whether the water supplying Coffs Harbour City Council residents comes from the Orara River or the Nymboida River, our water all comes from the same catchment.


The mighty Clarence River catchment is 22,716km2 in size, making it the one of the biggest river systems on the east coast of Australia.


The Clarence River catchment headwaters are found around Dorrigo to the south, near Glen Innes in the west, the NSW/QLD border near Woodenbong in the north and along the Richmond Range to the south of Whiporie out to the coast where the Clarence River empties into the Pacific Ocean at Yamba. It is estimated that the average annual flow of water in the Clarence River at Yamba is 5 billion litres.”


Friday, 5 March 2021

A perennial problem of dirty water in the Clarence Valley

 

The Clarence Valley hasn't had an official "boil water alert" in any of its towns or villages since January through to May 2013. 


Although in the chaos of the 2019-20 bushfire season water could not be drawn from a number of local water sources for a while due to ash, debris and fish kills.


However, that doesn't mean there aren't times in uneventful months when the house water coming out of the taps is discoloured, tastes musty or has a slight odour, which has some of us reaching for the emergency stash of bottled water and deciding that doing the laundry is not on the agenda.


Clarence Valley Council is again discussing the dirty water situation and I wince on reading of this discussion - because some of the worst episodes of dirty water tend to occur after a 'fix' has been applied.


The Daily Telegraph, 24 February 2021:


Surrounded by plentiful river systems, a large scale water supply dam and a longing for a time when anecdotally we had the best water in the country, many have questioned what Clarence Valley Council are doing about the ongoing issue.


Councillor Karen Toms took the opportunity at last week’s committee meetings to question general manager Ashley Lindsay about proposed plans to help with fixing the issue for residents.


Mr Lindsay explained that items in the upcoming budget would help address the problem, and that a much talked about water filtration system would not be a definitive solution to all the problems.


In response, The Daily Examiner put forward a series of questions to Council, to which manager of water Cycle Greg Mashiah responded.


It was said there were items coming up in the budget to do with fixing the water problem – what specifically will be proposed?


There is a proposal in the draft 2020/2021 operational budget for targeted air scouring of mains in Yamba and Iluka to reduce sediment deposits.


Do you believe there is a water quality issue?


One of the most challenging water quality issues faced by council is a dirty water event which is impossible to predict in duration, frequency and location through the pipeline. During these events, the water quality exceeds the aesthetic criteria of the Australian Drinking Water Guideline and creates numerous problems for the end user. Council’s main goal is to provide drinking water that is in compliance with the Australian Drinking Water Guideline and in line with our adopted standard of service which means the water is less than 5NTU (a measure of turbidity) 95 per cent of the time. In order to address the issue, council undertakes routine and targeted flushing of the mains, selectively draws water from the source with the best quality, monitors chlorine residual to the end of the pipeline and strategically plans water mains to reduce dead ends where possible.


Why is a $40 million filtration system being bandied around in the community as a solution?


Having a water source that is both clean and secure is one of the most important factors contributing to drinking water quality. The majority of Clarence Valley is privileged to have access to the water of the Nymboida River and the storage capacity of Shannon Creek Dam which provides us with valuable water security.


However, our existing treatment methods do not entirely protect us from the potential risk of poor water quality resulting from the impacts of climate change and environmental degradation. For example, council is restricted under its license from taking water from the Nymboida River when the flow is less than 225ML/day, which historically has occurred 5 per cent of the time.


During these periods, Council relies on the Shannon Creek Dam storage as a water source. The Shannon Creek Dam holds plenty of water, however the quality of the water is reliant on many factors including weather (especially rain), environmental contamination, algal growth and bush fires which could make the water unsuitable for use with our existing treatment system.


Our existing methods of treatment have a limited capacity to adjust to raw water changes. The main way Council currently manages its water quality is by “selective extraction”, where water is generally only taken when the turbidity is less than 5NTU. As outlined in Table 11 of the interim Drought Management Plan adopted by Council in October 2020 (page 35 of https://www.clarence.nsw.gov.au/page.asp?f=RES-GKQ-61-55-36), in the period 2013-2020 the Nymboida flow and turbidity was only suitable for extraction (ie flow >225ML/day and turbidity <5NTU) 76.5 per cent of the time, and if the Nymboida volume limit where extraction is permitted is changed to 430ML/day (which is foreshadowed in the Shannon Creek Dam water licence), Council could only have extracted water 44.2 per cent of the time in the last 7 years.


Council is undertaking a “secure yield study” as the first stage of updating its Integrated Water Cycle Management (IWCM) strategy which we believe will demonstrate that an upgraded treatment plant is required to enable extraction of water when turbidity is >5 NTU to ensure the system has sufficient capacity for current and future demands. The state government regulator (DPIE – Water) will require Council to adopt its IWCM strategy to demonstrate there is a requirement for a major treatment upgrade.


The investigation of further treatment (filtration) was also included as a risk management strategy in the new Drinking Water Management System which was adopted by Council in May 2020.


Council has allocated funds in the 2020/2021 budget for scope and design of Rushforth Road 32ML replacement reservoir, and the scoping study includes concept design of a possible future treatment upgrade including filtration to ensure future treatment is feasible with the replacement reservoir.


Will it fix the problem, or is there another underlying matter?


There are many contributing factors associated with dirty water events in the pipeline including but not limited to historical accumulation of sediment in the pipeline, a vast distribution system which challenges chlorine residuals in areas, changes in flow rates during peak periods of usage, seasonal fluctuations in water temperature, natural biofilms forming in the pipeline and natural and added minerals in the water. A filtration plant will improve water quality by reducing the turbidity of the treated water, improve our capacity to remove potential pathogens in the raw water, improve water colour and organics, improve taste and odour associated with algae and our protection against potential algal toxins.


While a filtration plant will improve water quality as a whole, Council cannot guarantee that it will completely eliminate all dirty water events due to the additional contributing factors, but there should be a significant improvement. Even if a filtration plant is constructed, because the natural water supply is very soft Council will need to continue to add lime to the water to increase its hardness. Council has added lime to its water supply since 2008 because the soft water means that over time the water dissolves metals such as iron, zinc and copper that make up water pipelines and fittings.


Even with the added lime, our water is still classified as “soft”. Properties which have water sitting in their household pipelines may still have these metals dissolved out due to the soft water. Customers may see the lime as a brown scale in their kettles or, if they have a water filter installed, the filter generally removes the lime which is why water filters clog up so quickly in the Clarence. Even if a filtration plant was constructed, because we will continue to add lime customers will still find they have a brown scale in their kettles and their filters will still clog up quickly. The best way to remove the iron scale from kettles is to boil vinegar in the kettle……..