Showing posts with label ORC. Show all posts
Showing posts with label ORC. Show all posts

Saturday, June 29, 2013

Irrigation Prospectus Withdrawn

Irrigation prospectus withdrawn
By Lynda van Kempen, on Saturday 29 June 2013
Otago Daily Times

Tarras Water Ltd has withdrawn its second consecutive prospectus after failing to find a dry shareholder for its proposed $36.5 million Tarras irrigation scheme and may have to ''concede defeat''.

The company received a double setback this week when the Otago Regional Council decided against investing $3.5 million in the scheme. It had the option to take up 30% of the ''dry'' shares, covering properties which chose not to irrigate.

Because of the regional council's decision, the Central Otago District Council's support for the scheme also lapsed. It had agreed to guarantee a bank loan of up to 20% of the capital cost of the scheme, but only if the regional council invested.

The proposal was to draw water from the Clutha River to irrigate 5999ha of Tarras land. The scheme aimed to ease demand on the Lindis River. The regional council said the company had not met council-imposed conditions and the risk of not being able to on-sell the dry shares meant the investment was too risky.

Earlier this month, the company withdrew its first prospectus, after failing to meet its 70% threshold for ''wet'' shareholders. It issued another prospectus with a 65% threshold for wet shareholders. Yesterday was the closing date for the latest share offer but it withdrew the prospectus yesterday afternoon.

''Despite its best efforts, Tarras Water Ltd has been unable to secure interest from a party prepared to be a dry shareholder within the current prospectus time frame,'' a statement from the company's board said.
The company had signalled in the prospectus it needed support through a dry shareholder, applying for redeemable preference shares, ''to allow the proposed scheme to be built to optimise its potential''.

It had explored all the options in terms of dry shareholders, including considering seeking support from the Crown Irrigation Fund, but the fund would not be functional until next month, company secretary John Morrison said.

''Therefore, the TWL board wishes to advise that as at the closing date for the prospectus, no shares can be allotted as terms and conditions of this prospectus will not be met.''

Asked yesterday whether the board was ''conceding defeat'', Mr Morrison said: ''I guess we're conceding, on this particular scheme.''

The board would be meeting soon to ''take stock of where we're at'' and consider its options, he said.

The board's statement said ''mindful of its responsibilities to the Tarras district, the board will now consider its options, including any subscription cheques or deposits held by TWL being returned to their owner''.
Mr Morrison declined to elaborate on other options being considered by the board.

More...

Friday, June 28, 2013

Central Otago Water Scheme Rejected

Central Otago water scheme rejected

Friday 28 June 2013
Radio New Zealand

The Otago Regional Council has rejected a request to put money into a Central Otago water scheme and the decision may end the $39 million project.

The Tarras Water Scheme would irrigate farmland in the Ardgour Valley, taking water from the Clutha River to supply 40 properties covering about 6000 hectares in the district which lies between Cromwell and Wanaka.

But council chief executive Stephen Woodhead said on Thursday that the backers of the scheme have failed to meet several council-imposed conditions.

Mr Woodhead said the council was asked to contribute $3.5 million by way of dry shares. But there was a risk they would not be able to sell those shares in the future to recoup costs.

The council also said it couldn't ignore the depth of feeling in parts of the community about the wisdom of the regional council investing ratepayer money in an irrigation scheme or its impact on rates.

A spokesperson for Tarras Water said he is unable to comment until the share offer on the scheme closes on Friday.

More...

Tuesday, June 25, 2013

Call To Reject Irrigation Scheme

Call to reject irrigation scheme
By Rebecca Fox on Tuesday 25 June 2013
Otago Daily Times

Investing in Tarras Water Ltd's proposed irrigation scheme is too risky for the Otago Regional Council, its staff say.

They are recommending the council not invest in the $36.5 million scheme. The option was to take up 30% of ''dry'' shares (covering properties which choose not to irrigate) to irrigate 5999ha in Tarras.

Councillors will make a final decision on the $3.35 million investment, which had already cost the council about $250,000, at a meeting in Dunedin tomorrow.

It will end a six-month debate which included the council controversially overturning a hearing panel recommendation not to give it the option of investing in the scheme.

The council since had struggled to get the information it needed from the company to make an investment decision.

In the meantime, Tarras Water had issued two prospectuses, the second changing the form of the scheme and reducing the ''wet'' share (landowners who take up the option to irrigate) take-up from 70% to 65%.
In a report to be considered by the council, corporate services director Wayne Scott said it was very disappointing Tarras Water had made ''fundamental'' changes to the scheme without any contact with the council.

''The reissued prospectus moves further from common ground.''

It also meant conditions the ORC had set in its long-term plan amendment to allow investment were not met by Tarras Water.

A significant risk was the uncertainty around the council's ability to on-sell the shares not taken up by landholders, he said.

The new prospectus raised doubts over landowners having to buy shares from the council or taking up their full allocation.

This risk was greater than first assessed and the council was aware of at least one 100ha property in the area where owners had installed their own irrigation scheme.

''It is our view that the identified dry shareholder investment does not appear entirely robust,'' Mr Scott said.
As a result, the council could be left holding dry shares which would offer no return.

The council had sought independent advice, including a financial and investment risk report from Ernst and Young, an engineering review from Beca and advice on its possible liabilities under the Securities Act.

While Beca reported the scheme was sound, Ernst and Young advised the scheme was not designed to deliver a commercial return to shareholders.

It also noted the largest 10 landholders represented 83% of the scheme area and four of those owned 55%, and the debt repayment period had been extended to 47 years, longer than the water permit term of 35 years.

While a return on the council's investment is planned, it would not be a normal rate of return considering the associated risks, according to the Ernst and Young report.

The council's support had been based on it being a community scheme providing water for domestic, stock and fire-fighting use, Mr Scott said.

As Tarras Water had reduced the scheme's size, it appeared to be for irrigation only.

The public, through the long-term amendment and annual plan processes, had shown its opposition to the council funding the scheme and many who once supported it no longer did because of the loss of community services.

If the regional council accepted its staff recommendation, it could put the Central Otago District Council's bank loan agreement with Tarras Water - up to $8 million, or 20% of the capital cost of the scheme - into question as it was conditional on ORC support.

It would also mean the regional council's general rate increase would only be 2.97%, not the 5.34% proposed if it went ahead with the Tarras investment.

Tarras Water Ltd chairman Peter Jolly was on holiday in Fiji and could not be contacted yesterday for comment. Company secretary John Morrison, who was in Melbourne, declined to comment as he had not seen the council report, and said nobody from the company would be able to comment at this stage.
 


Tarras scheme • Take water from Clutha River to irrigate land in Tarras.
• Initially proposed to cover 7630ha - now 5999ha.
• Was to include water for firefighting, town and domestic supply - now it will not.
• Cost $36.5m.70% take up of ''wet'' shares amended to 65% after investment fell short.
• ORC to take up 30% of dry shares worth $3.5m.
• CODC to guarantee bank loan if ORC gives its support.

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Friday, January 6, 2012

Contact Vies For More Time

Contact vies for more time to establish hydro scheme
By Lucy Ibbotson, on Friday 6 January 2012
Otago Daily Times

Contact Energy has asked for more time to establish a hydroelectric scheme at Lake Hawea, citing the global economic downturn and seasonal construction constraints as reasons for the delay in exercising the project's original consent.

Contact has proposed the construction and operation of a small-scale hydro-generation facility in the outfall control structure of the existing Lake Hawea dam.

It secured an original land use consent from the Queenstown Lakes District Council in 2007 for the 17.2MW Hawea Gates Generation Project, due to lapse on February 7.

Contact also holds associated consents granted by the Otago Regional Council with expiry periods of 10 and 15 years, lapsing on various dates in 2017 and 2022. It wants to extend the expiry date of the QLDC consent another five years, to July 16, 2017, to coincide with the regional council consents.

Contact hydro-development project manager Neil Gillespie said, while Contact was "continuing to progress, giving effect to the consent", it was not possible to complete the final design and construction of the project within the current QLDC consent period.

The extension application said a combination of "technical, practical and economic constraints" were behind the delay.

The project was not straightforward as it involved "retrofitting a modern tailor-made generation plant to existing infrastructure", making the economic risks of project high, the application stated.

A final investment decision could not be made by the current lapse date, a situation "exacerbated by the global economic downturn and associated slower-than-anticipated growth in electricity demand since 2008".

Also, because initial construction work had to be performed "in-river", the project was limited by the ORC consents and seasonal constraints, which had contributed to its extended duration.

The project requires modifying the Hawea dam structure, on Contact-owned land, by constructing twin powerhouses; installing a generation plant; altering the intake structure; installing penstocks through the existing sluices; strengthening some existing works; and carrying out earthworks and upgrades to access roads.

Mr Gillespie said the extension would help achieve the objectives of the QLDC district plan and was an efficient and sustainable use of the resources.

"It's a great little project, renewable, small scale, and makes the most of an untapped resource, the water already being spilled through the dam.

"Importantly, the development involves no long-term changes to the river environment."

It would take up to 36 months to complete the final design and construction, and the expected timeframe to complete all work is no later than 2017, in line with the current ORC consents.

Contact was "still working through [geotechnical] information" on the four other Clutha River locations identified as options for hydroelectric dams - Luggate, Queensberry, Beaumont and Tuapeka Mouth - Mr Gillespie said.

More...

Saturday, October 29, 2011

New Bridge Uncertainty

New bridge uncertainty
By Matthew Haggart, on Saturday 29 October 2011
Otago Daily Times

Beaumont Bridge. Photo by Craig Baxter. Extending the life of the 123-year-old Beaumont Bridge across the Clutha River is expected to cost upwards of $590,000 during the next five years.

The New Zealand Transport Agency is prepared to pay at least this sum while it deliberates what it might cost to design and build a new structure.

A decision on replacing the bridge may be on the backburner because a hydro dam could be built downstream from Beaumont, flooding the Beaumont Valley.

Contact Energy hydro projects manager Neil Gillespie said the company had not been in consultation with the NZTA about any future structure which might replace the Beaumont Bridge.

If Contact built a dam at Tuapeka Mouth, it could affect the bridge site and State Highway 8 through the area.

Mr Gillespie said Contact had always acknowledged it would have to provide mitigation measures, once a decision was made about the future of any possible hydro scheme.

Over the past five years, about $1.29 million has been spent by the NZTA as it tries to extend the life of the run-down, ageing structure.

The SH8 bridge has been back in the headlines after the NZTA recently denied the structure was unsafe after Waitaki deputy mayor Jim Hopkins questioned whether several safety features were put in place to stop it collapsing.

NZTA southern region director Jim Harland told members of the Otago Regional Council's (ORC) transport committee the bridge was not in danger of falling down.

It was preferable to replace the bridge and the NZTA was still considering its options about when that might happen, Mr Harland said.

NZTA Otago-Southland operations manager Roger Bailey said forecast expenditure to maintain the bridge might vary.

About $28,000 is forecast to be spent each year to maintain scaffolding on the bridge, set up to carry out regular monitoring, structural inspections, testing and minor routine repairs.

About $60,000 is to be spent every year to maintain and repair "surface running boards" on the structure, "which tend to loosen, wear out and crack", Mr Bailey said.

The NZTA also incurred costs of about $30,000 a year in consultants' fees to monitor the maintenance programme, he said.

"If our monitoring identifies any unforeseen structural problems, there would be additional costs that we cannot predict," Mr Bailey said.

NZTA transport planning manager Ian Duncan said it remained cost-effective to continue to maintain the bridge during the next five years.

If any new bridge built was affected by Contact's plans, then the power generator would have to "come to the party", he told ORC transport committee members.

More...

Thursday, February 10, 2011

Missing Man's Body Returned Home

Missing man's body returned home
By Barbara Withington, on Tuesday 10 February 2011
Southland Times

For some it meant closure, others saw it as nothing short of a miracle.

Family members gathered at the Beaumont Jet office yesterday morning as the body of Paul Wilson was bought ashore from the swollen Clutha River, ending seven days of searching since the 28-year-old civil engineer went missing in the Talla Burn stream while collecting water samples.

With the Clutha River flowing at about 1300 cumecs (normal flow about 800 cumecs), dropping from a high of almost 1550 cumecs on Tuesday morning, fears had been held Mr Wilson's body would never be recovered.

In normal river flow, the body of 16-year-old Darryl Walker, who dived into the Clutha River 1km south of Roxburgh on November 11, 2008, was never found.

In a media release, Detective Sergeant Derek Shaw said Dave Crawford, of Beaumont Jet, continued to observe the river and had discovered Mr Wilson's body about 11am.

"We believe Mr Wilson has always been within the search area but had only recently become visible," Mr Shaw said yesterday.

Police also thanked Central Otago LandSar, volunteer searchers, local farmers and Contact Energy, who all assisted in the search.

Mr Wilson had been the project engineer for Talla Burn Generation, a run-of-the-river power scheme developed by his father Jeff Wilson in partnership with Beaumont Station owner Alan Hore.

The scheme began producing up to 2.6megawatts of power in early November.

One of the conditions placed by the Otago Regional Council on the project was that regular water samples be taken, and it was while he was carrying out sampling of the Talla Burn in flood that Mr Wilson disappeared.

Senior Sergeant Andy Reed, who was involved in the search for and recovery of Mr Wilson, was a neighbour of Mr Wilson's parents but said he felt the loss no more than anyone else.

"Anyone in Roxburgh who has anything to do with the family will be feeling it for them," Mr Reed said.

The matter has been referred to the coroner.

Mr Wilson's family asked for privacy

More...

Tuesday, February 8, 2011

More Flooding For South Otago

More flooding tipped for South Otago
Tuesday, 8th February 2011
Otago Daily Times

The Otago Regional Council is predicting further flooding of rural farmland near Balclutha after heavy rain caused surface flooding in South and West Otago yesterday.

Although many rivers in the area are dropping, the ORC is predicting the Clutha River to peak at around 1900 cumecs at lunchtime today. This means low-lying areas close to the river, up and downstream of Balclutha, will flood, adding to the already high water levels in the lower Clutha delta.

Because Clutha river flows upstream at Roxburgh Dam are above 1400 cumecs, the lower Clutha is expected to remain high for several days.

More...

Saturday, August 21, 2010

ORC Concern Over Dam Safety Rules

ORC concern over dam safety rules
By Rebecca Fox, on Saturday 21 August 2010
Otago Daily Times

The Otago Regional Council does not think dam owners are capable of managing safety under a more relaxed regulatory regime.

A new dam safety scheme, due to have come into effect in July, was delayed to allow for an independent review after concerns about its potential compliance costs.

That review found the scheme was needed but required modifying to improve its efficiency and reduce compliance costs.

It also recommended the definition of a large dam be increased, eliminating an estimated 36% of "low-impact dams" from the requirements of the scheme.

The Department of Building and Housing consulted on the review, receiving 33 submissions, including one from the Otago Regional Council.

It would now analyse the submissions and report back to Government in the next month "or so" with advice on which recommendations should be implemented, a department spokesman said.

The regional council has been the building consent authority responsible for dams in Otago since May 2008 and for dams in Southland and the West Coast from July 2008.

In its submissions on the proposed changes, the council said dam owners had not demonstrated to the council they would be "capable of responsibly managing safety" under a more relaxed regulatory regime.

"Further experience shows that the industry is not meeting regulatory requirements that have existed under the Building Act for almost two decades."

Council environmental engineering and natural hazards director, Gavin Palmer, said in an interview dam safety was very important, as unlike most other structures, the effects of any failure would be felt off-site.

"Its an important issue . . . for anybody who lives downstream of a dam . . . who is thinking of buying property."

At present, there was a "vacuum" in the power available to the council to act if it had concerns about the "integrity" of a dam, although it did if there was immediate danger, he said.

Under the scheme as it stood, dam owners would have had to inform the council of their ownership, but with the proposed reduction in size, there would be no legal requirement for owners of smaller dams to do so.

"It makes it hard to assess the scale of the problem."

As to the suggestion of centralising the dam safety scheme functions, the council only believed it would work if central government took on all the Building Act dam responsibilities.

Otherwise, it was comfortable with the requirements to stay with regional councils.

"It's really important it is done as a coherent whole."

The Department of Building and Housing said the review recommended the authorities administering the dam safety scheme should have the power to deal with risky "smaller" dams.

This power would enable dams that would not otherwise be in the scheme to be managed, he said.

More...

Clyde Dam Highly Problematic

Since the filling of the Dunstan reservoir behind the Clyde dam was completed in 1993, the Clyde dam controversy has faded in the minds of most New Zealanders. But the woes of the last 'think big' project have not gone away. Despite extensive and costly mitigation measures, issues remain regarding gorge instability, faultlines, and reservoir sediment build-up.

The Cairmuir-Dunstan Fault cuts across the gorge just above the dam, and the River Channel Fault disects the dam and the powerhouse. The discovery of the River Channel Fault came as a surprise to dam workers, who uncovered the micro-fractured rock running in a wide band along the riverbed. Obviously, fissured rock is not suitable for dam foundations. The first solution was to pump vast amounts of slurry concrete into the fault, but concerns mounted over the extent and depth of the faultline, and the likely futility of 'dental' concrete.

Finally, experts were called in to determine the extent of the fault issue. It was calculated that the River Channel Fault was 12-15km deep. This lead to a dam re-design in 1982 (during which a sluice channel was omitted leading to later modifications that reduced the dam's MW output by one-third). Subsequent investigations carried out by a team of some 40 geologists revealed serious instability issues throughout the gorge. The result was an incredibly expensive gorge stabilization programme, costing $936 million dollars (2005 value), resulting in the total cost of the project blowing-out to $1.4-1.8 billion dollars. The exact cost is unavailable or unknown, suggesting the true cost could be even higher.

There was considerable doubt over whether or not the dam would be safe, but in the end the government of the day, under Prime Minister Robert Muldoon, refused to admit that the project had been botched, and it was finished, complete with a controversial 'slip-joint' to accommodate earthquakes up to, supposedly, 7 on the Richter Scale.

The 'slip-joint' was hailed as an engineering achievement, but one of New Zealand's most respected geo-technical scientists at the time, Gerald Lensen, insisted that it was designed incorrectly, because the River Channel Fault is 'tensional' (pulling apart) and not 'lateral' (slipping sideways). Needless to say, this fact has been kept quiet ever since.

Now, according to GNS scientists, the 'big one' is overdue along the Alpine Fault (bigger than the 7.8 Fiordland quake in July 2009). Meantime, the 6,500 measuring and monitoring stations quietly observe the landslide movements, reduced but not stopped, and visible silting up continues in the Kawarau Arm at an alarming rate estimated to be 1.46 million cubic metres per year, building up the reservoir bed profile by an estimated 1.85m annually.

The Decline of Large Hydro

In the 21st century, energy that is "renewable" is defined as energy from a source that is both naturally replenishing and environmentally safe and sustainable. The term “new” renewable energy has also been used to define the latest wave of renewable technologies that are truly environmentally sustainable.

By such standards, hydropower over 10 MW is no longer considered renewable because the negative impacts of large hydropower outweigh the so-called renewable benefits, which have inherent limitations.

In New Zealand, we are told that to maintain our present society and standard of living we need a minimum increase in power availability of 2.5% per annum (peak power), with 170 MW of new generation added each year. Based on this figure, we would need the equivalent of one Luggate dam (86 MW) every 6 months, or one Tuapeka dam (350 MW) every 25 months, or another Clyde dam (432 MW) every 29 months. Clearly, this is not a credible long-term solution.

World-wide, large hydropower declined in the 1990s because of mounting opposition that culminated in the World Commission on Dams report (2000), which acknowledged that large dams do not meet best practice guidelines in the water and energy sector. The global recession spurred more large dam projects, especially in developing countries, but the tide has turned and large hydro is again in decline as new renewable technologies sweep the world.

The intrinsic problems associated with large dams have long been glossed over. Hydroelectricity is often falsely promoted as cheap and reliable. While the operating costs of hydroelectric dams can be relatively low, their construction costs are extremely high, running into the billions of dollars for major projects. They are also prone to cost overruns. The WCD (World Commission on Dams, 2000) found that on average dams cost 56% more than forecast. And 55% of the hydroelectric projects studied by the WCD generated less power than planners promised.

New Zealand's Clyde dam is an obvious example of disastrous cost overruns. According to the public record, the 1982 winning bid from the joint venture of W. Williamson & Co. of Christchurch and Ed. Zublin AG of Stuttgart, was $102.6 million. Ten years later when the dam began producing power, the cost had climbed to $1.4 – 1.8 billion. Conversely, the planned generation of 612 MW had fallen to an actual capacity of 432 MW.

Typically, construction and mitigation costs are under-estimated, long-term costs are ignored, the value of the proposed dam and mitigation measures are inflated, while the value of the current and potential benefits from the existing environment are under-reported.

The proponents of large dams also invariably claim that large hydropower is "green" energy. However, the carbon footprint of a large-scale hydro project is anything but "green". A comparative study at the University of Auckland found that large hydro has a full-life carbon footprint that is 2.5 times larger than that of tidal energy.

A similar comparative study in the U.K. found that in terms of grams of CO2 equivalent per kWh of electricity generated, large hydro in the U.K. comes in with a carbon footprint 2 to 6 times larger than that of wind power. Specifically, large hydro has been measured at 10-30gCO2eq/kWh while wind has been measured at only 4.64gCO2eq/kWh, the lowest except for nuclear (Carbon Footprint of Electricity Generation, 2006).

It is easy to understand why large dams rate so poorly. For example, the Clyde dam contains 1 million cubic metres of concrete, equivalent to about 3 million tonnes. Manufacturing one tonne of cement requires 4.7 million BTU’s of energy, which is the amount contained in about 170 litres of oil or 190 kilograms of coal. Obviously, this combined with emissions from machinery involved in earthworks for foundations, roading, terrain forming, landslide mitigation, and through the loss of river corridor carbon sink forests or vegetation, adds up to an enormous carbon footprint.

There are over 54,000 large dams in the world, some 5,000 of which are over 50 years old. The typical design-life of such dams is 80 years, and an increasing number of old dams are being classified as high risk. It is a telling fact that more dams are being decommissioned than built in the U.S., but dam owners typically avoid decommissioning issues and try to evade the considerable costs associated with dam removal and river restoration. This scenario points to a looming dam safety crisis.

In the past, the benefits of large dams were viewed as outweighing their obvious short and long-term environmental impacts. That has changed.

Large hydropower once represented the epitome of 20th Century technology and a passport to prosperity, projecting a misguided belief that Nature could be controlled without consequences. In the 21st Century, we face a new reality, for which 20th Century energy solutions are unacceptable.

Roxburgh Dam Decommissioning?

The Roxburgh dam was commissioned in 1956, and it is New Zealand's oldest concrete gravity dam. Such dams have a design lifespan of 80-100 years, but the actual lifespan of a dam depends on the rate at which its reservoir fills with sediment. Assessing the remaining life of a dam and reservoir is complex, but reservoir flooding events indicate that time is running out.

When other issues are added to the picture, questions must be asked.

The Roxburgh dam - like the Clyde dam, has faultine and landslide issues that are potentially catastrophic (something which has been kept quiet). However, when the Roxburgh dam was built, there was minimal geotechnical investigation and mitigation undertaken, despite obvious evidence of major landslides in the Roxburgh Gorge, notably at Island Basin.

But reservoir sedimentation is the most problematic issue. In fact, within 15 years of the dam's commissioning, the dam's two low level sluice gates were inoperable, and since then the silt burden has filled much of the Roxburgh reservoir reaching back to Alexandra. In 1995, ECNZ estimated that 1.5 million cubic metres of silt had entered the Roxburgh reservoir every year before the Clyde dam was built, and that a total 50 million cubic metres of silt had accumulated in the reservoir, raising the bed profile 'considerably'. Attempts to 'flush' the silt have had little effect, and have not reversed this process. This is probably because of the 'Gates of the Gorge,' a narrow bottleneck just below Alexandra.

As a result, Alexandra has become flood-prone, and has installed flood defence walls along the river. But even these will not be high enough to prevent future flooding, because the riverbed will gradually keep rising. It was thought that by building the Clyde dam that this sedimentation problem would be largely solved, but some silt still gets through to continue choking the reservoir and river, and the Manuherikia River still contributes silt when it is high.

Efforts continue to "buy time" for the Roxburgh dam. More "flushing" will only move some of the sediment load further toward the dam. (Flushing has failed to remove sediment wherever it has been tried, including on the Colorado.) Physically removing millions of cubic metres of sediment is not practicable because of the costs involved. An interim measure is to remove some sediment from the Manuherikia confluence, and also from the Galloway area, but this does not address the major constriction at the 'Gates of the Gorge.'

The most desperate strategy is to raise the operating level of the Roxburgh reservoir, and this was done in 2009 when a rise of .6m was consented. While this allows water to reach the dam more easily, it also increases the risks associated with flooding events, both at Alexandra and the dam. In the life cycle of a dam, this is the "Russian roulette phase."

The dam owners and the Crown must face up to the fact that the Roxburgh dam and reservoir will not last forever, and that enormous risks are imposed on communities in the meantime. A feasibility study is needed to determine the most effective decommissioning and de-silting methodology. Where such dam removal projects have been undertaken overseas, the costs as a proportion of construction, range from 35% to 150%.

However, since there has been no provision for the ultimate decommissioning of the Roxburgh dam (typical of the hydropower industry), there is something of a head-in-the-sediment policy on this issue.

Questions should be asked, including the most difficult question of all ... when the time comes to decommission the dam, who will pay?
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