a "National Heritage Place"
Cerberus Newsletter No. 198
8 April 2018
Application for Permit to Fill Cerberus with Concrete Lodged
Bayside has lodged its application to fill Cerberus with concrete and addressed any of Heritage Victoria's concerns. On the 24th of April Heritage Victoria will start assessing Bayside's application and presumably approve it. We are concerned that approval is a foregone conclusion given the statements below that were made by the then Mayor of Bayside, Cr. Alex del Porto on the 24th of October 2017.
"The concrete infill is supported by both the Federal [Heritage] Department and Heritage Victoria."
"This [concrete infill] is the way that we were told by both the Federal Minister and by the Heritage Victoria rep, who came and spoke to us, this is the way forward for them."
We believe that the Heritage Victoria rep. referred to is Steven Avery, the current Executive Officer of Heritage Victoria.
Text above in square brackets is my addition.
When asked whether Alex del Porto's claims were correct, Steven Avery replied:- "No decision has yet been made as to whether or not the works proposed for the site will be permitted."
The use of concrete is not heritage based. Our suggested heritage based alternative has not been genuinely investigated. Bayside's June 27 motion specified concrete as the preferred method and an attempt to have it removed from the motion was defeated.
Understandably Bayside's officers took their guidance from Council's fixation with the concrete solution and did not pass on information that we provided on September 14 on the use of polyurethane, to their Archaeologist writing the Heritage Impact Statement (HIS).
Numerous criticisms of foam solutions in the Heritage Impact Statement (HIS) are simply wrong.
- The HIS states that foam cannot be pumped from shore. Tank Foam and Polyurethane can be pumped from shore.
- The effect of fire on foam was assessed as high risk. The Safety Data Sheet for Tank Foam states "Polymer is non-flammable: does not ignite or burn".
- As it is not proposed to fill the entire ship with foam then excessive buoyancy would not be an issue.
- Tank Foam and Polyurethane are environmentally neutral and therefore pose no danger to the environment. As the Tank Foam would be mixed on shore by a trained operator there would be minimal risk from spillage and not the high risk stated in the HIS. Polyurethane is suitable for potable water contact.
- The HIS further states that "Cured foams have quite a low compressive strength". This is not true. Polyurethane has a very high compressive strength of 1,027 psi when used in conjunction with fine sand, such as found in Cerberus. Even without a continuous layer under the turrets, Polyurethane would be able to support many times the weight of the turrets and guns.
- Contrary to what is stated in the HIS, both Polyurethane and Tank Foam have been successfully used in marine environments for many years. The earliest example that we are aware of is in the 1960s to extend the service life of leaking cutter-suction dredges by filling them with polyurethane. The most recent example is on the 5th of April this year in conjunction with a large oil refinery with very stringent environmental requirements. Both Polyurethane and Tank Foam are used to repair sea walls.
The Age, 28 March 2018
Naturally we will be making a submission to Heritage Victoria. Anyone wishing to do likewise should be aware that submissions should be posted, and NOT emailed, to Heritage Victoria, PO Box 500, Melbourne 8002.
Any overseas supporters wishing to make submissions can email them to us via firstname.lastname@example.org and we will post them to Heritage Victoria.
It cannot be emphasised enough that Heritage Victoria will decide later this month whether to fill Cerberus with concrete. All indications are that the application will be approved.
By my reckoning, 1,700 cubic metres of concrete will require over 200 concrete trucks to fill Cerberus. A horrifying thought. What a way to treat a place on the National Heritage List.
What is Wrong with Concrete Infill?
Filling Cerberus with concrete has no heritage merit as concrete:-
In summary, concrete infill has no heritage benefits and is purely an attempt by Bayside to hijack a heritage grant for its own legal liability concerns.
- Will not support the turrets?
The 24 October report to Council points out that the concrete infill method would not provide sufficient structural support to enable the guns to be returned to the ship. As the weight of two guns would only add 36 tonnes to each 158 tonne turret, one has to ask whether the calculation of the load that the concrete infill can support is so precise as to determine that the concrete will support 158 tonnes but not 194 tonnes, which is only 23% extra. If this is not the case then one must conclude that the concrete infill will not support the turrets and that they will still collapse. Surprisingly the HIS fails to mention that the guns cannot be returned to the ship due to the lack of structural support.
- Will greatly increase the weight of ship on the same footprint. More than doubling the weight of Cerberus by adding 2,400 tonnes to the existing 1,900 tonnes on the same area of the seafloor will presumably cause Cerberus to settle further into the sand thereby changing its profile. Supporting the turrets with polyurethane will not have this effect.
- Is non reversible. Commenting on the important heritage principle that any works should be reversible, the HIS makes the surprising claim that "Concrete infill could be removed if necessary but would be difficult and expensive." Presumably this would not involve divers with jack hammers inside Cerberus. One wonders how any removal process would not cause the ship to totally collapse.
The statement in the HIS that Walker and Marquis-Kyle in their commentary on the Burra Charter do appear to offer a lifeline to Cerberus in their assertion that "…Non-reversible changes should only be used as a last resort…" fails when it is realised that the Polyurethane solution was not properly explored.
Why is the Polyurethane / Tank Foam a Solution Superior to Concrete.
The Polyurethane / Tank Foam solution is a heritage based solution in that it:-
- Provides Support for the Turrets & Guns. Polyurethane could be injected under the gun turrets to prevent their collapse. Setting within seconds on contact with water it would remain under the turrets expanding to fill the void between them and the silt layer below. Lower cost Tank Foam, pumped from shore into thin polymer bags, could be used to fill openings in the side of the ship to limit access, thereby addressing Bayside's legal liability concerns.
- Adds no weight to the ship by the Polyurethane under the turrets and the Tank Foam filling openings.
- Is reversible.
David versus Three Goliaths
In 2000 the various stakeholders comprising Heritage Victoria, Parks Victoria, the National Trust, the City of Bayside and two community members (myself and Gary Grimmer) met to investigate ways to preserve HMVS Cerberus. This group became known as the Save the Cerberus Alliance.
In 2002 Friends of the Cerberus Inc was formed to involve the broader community in support of the Alliance's goal of preserving HMVS Cerberus. In 2003 the Victorian Navy was reactivated as the membership arm of Friends of the Cerberus. In 2004 Friends was successful in applying for a grant of $80,000 to remove the guns from Cerberus in order to delay a collapse of the turrets. In 2005, after being co-nominated by Friends and the National Trust, Cerberus was listed on the National Heritage List. in 2008 Friends successfully applied for an NHII grant of $500,000 which was held on our behalf by the National Trust who, six years earlier, had offered to set up and manage a Cerberus account.
Sometime around 2009 the City of Bayside reversed its claim of NOT owning Cerberus to now being its legal owner. Whether this was because of logic prevailing or because of the presence of the NHII grant is not known.
In 2011 Bayside generously agreed to project manage an investigation of methods of supporting the collapse of the turrets. Although we were involved in this process a pattern emerged of documents not being shared with us and misleading statements being made. We were able to defeat the final recommendation with the support of a unanimous Council motion on the basis that filling Cerberus with sand would not work and would wash out of the ship. Interestingly sand filling it is now described in the current Heritage Impact Statement as having been a "short-term expedient only". Since 2012 we have not been consulted, nor to our knowledge has the National Trust.
Recent EventsAfter the promotion of Minister Greg Hunt who was a strong believer in community consultation, away from Heritage, representatives of the Federal Heritage Department met with the now head of Heritage Victoria and the City of Bayside to formulate a new approach. Neither we or the National Trust were advised of this meeting or of its outcome until well after the event. It is rather sad that community consultation was so feared that the two community groups that successfully nominated Cerberus for the National Heritage List, one of which successfully applied for the $500,000 NHII grant that was held by the other group, were both excluded from the concrete infill proposal discussions. We were informed of the secret meeting well after it had occurred, excluded from the concrete infill investigation and only advised of its outcome six days prior Council voting on it. It appears to be a case of a Federal Government Department, a State Government body and a Local Government body conspiring to sideline and ignore community concerns. David versus, not just one, but Three Goliaths.
Would we rather see Cerberus Collapse than Filled with Concrete? NO!
Contrary to what is written in the HIS, we have never stated, nor is it our private opinion or our policy that we would rather see Cerberus collapse than filled with concrete. When asked about his statement in italics below, the HIS's author quoted my comment in Newsletter 195:-
Newsletter 195, 26 Oct 2017 "Irreversible - As Councillor Long pointed out, and is clear to all concerned, concrete cannot be removed from Cerberus once it has been pumped in. This constitutes a terrible heritage outcome and Friends of the Cerberus would prefer that nothing was done rather than that the ship was destroyed by this irresponsible action."
To quote this as proof that I have been heard and reported as saying that we would rather see Cerberus collapse than filled with concrete seems to make a huge inference and yet is sadly consistent with the many other inaccuracies in the Heritage Impact Statement.
Our preference for doing nothing was so that a better solution could be found, such as the Polyurethane / Tank Foam solution, details of which had been provided for the author to consider over a month earlier in mid September and which he finally learnt about on October 16. This was our same view with regard to the 2012 sand fill proposal. By killing it off the opportunity is now available to implement a heritage based solution that will work.
Statement in Heritage Impact Statement - "Nevertheless, members of the public having high profiles within relevant interest groups have been heard and reported as saying that they would prefer to see Cerberus collapse rather than concrete infill being used. The motivation for this stance appears to range from petulance over rejection of a pet scheme to earnest reservations concerning reversibility."
Winners of Membership Renewal Prizes.
Congratulations to Tim Horton who won the original 1869 engraving of Cerberus, to Val Weber who won the book Nelson's Victory by Brian Lavery and to Marcus Phillips who won the book Wooden Warship Construction, also by Brian Lavery. Many thanks to one of our members, Commander Andrew Braden (VN) for donating both books for use as prizes.
|Click engraving to enlarge.|
Fleet Engineer (Victorian Navy)
website, research & Friends of the Cerberus President.