Our tiny swimming pool has a new leak, forming a new stalactite and a stalagmite beneath it - April 2019

Dripping stalactite is evident in above picture

Moist stalagmite in above picture

Based on appearance in the below URL thread of white stalactites removed last year, the white marks in the above and below pics may be three possible new stalactites in early formation.

White stalactites and a large stalagmite and a brown stain in the concrete in the carpark on Level 5 beneath 8.4m long swimming pool - March 2018

Philip Johnston, Chairperson, who identified stalactites hanging from the ceiling under the pool early last years, has observed the early development of a stalagmite which is positioned where vehicles drive over it when departing the carpark and again when returning to the carpark.  It is generally dry around 9am and again around 7pm and patently moist around 5am and again by midday.  For water from the 8.4m pool to penetrate 20" of high MPa concrete, a lot of water must also be penetrating at least 20" in all directions (from at least one leak point in the pool), passing over rio rod steel that provides the structural strength to the 20" concrete slab.  That steel rod will eventually rust and lose its structural integrity and cracks will appear.

The expression "an in ground swimming pool" is an expression that we are all familiar with.  There are a lot of backyard swimming pools and 50 metre council pools that are sitting in sandstone or similar rock. When those swimming pools leak, they leak into the sandstone et al base. The expression "an in slab swimming pool" is not a familiar expression because there are very few of them, because when they leak, it is a much bigger problem.


Trying to identify and stop leaking from a 25 year old swimming pool mounted in a 20" floor slab is more difficult than looking for a needle in a haystack.  If it was found, it would not be too long before another leak, and another leak, appeared.  Concrete is not a good vessel to store water long-term as noted in Philip Johnston's email to Strata Committee members on 3 July 2018:      

"Hornsby 50m and (Andrew) Boy Charlton 50m swimming pools required complete replacement due to concrete cancer.  Shortly North Sydney 50m concrete swimming pool will be replaced in its entirety due to water leaking through a concrete slab and the resultant concrete cancer.

Fluids eventually penetrate concrete, rust/expand the reinforcing rods thereby destabilizing the concrete.  I do not want that to occur at The Pavilion, because the consequences may be catastrophic, because our small pool is suspended above carparks, not sunk into sandstone."

Philip Johnston's initial email to the Strata Committee members sent 26 March 2018 titled "Section 37 ‘Duty of members of strata committee’ of ‘Strata Schemes Management Act 2015’ behooves our Strata Committee to appraise the cost-benefit of de-commissioning 22 year old concrete pool - costs exceed benefits - alternative 'value added' usage" included:

"Mindful of the high on-going and one-off costs of our 8.3m x 3.85m x 1.4m swimming pool, Section 37 ‘Duty of members of strata committee’ of my 5th Attachment ‘Strata Schemes Management Act 2015’ behooves the Strata Committee to appraise the merits of de-commissioning the 22 year old concrete pool and replacing it with a “Owners Entertaining Common Room’ which would be a more appealing ‘common room feature’, with greater usage and relatively miniscule on-going costs.   

The swimming pool could be covered in with a robust timber floor for $7,000 circa.   

The area could be equipped with the following for another $3,000:

sink, fridge, TV, electric bar-b-que and micro wave, three tables and 18 chairs

Owners could book an ‘Owners Entertaining Common Room’ on-line for a birthday party or if they wanted to invite their friends/family to watch a football grand final, test cricket etc. 

‘Owner users’ would be responsible to leave the ‘Owners Entertaining Common Room’ in the state they found it.


If any member of the Strata Committee believes that the ‘benefits’ of maintaining our 22 year old swimming pool exceed –

·         the afore-mentioned on-going and periodic ‘costs’; and

·         the utility of an ‘Owners Entertaining Common Room’ that involve relatively miniscule on-going costs,

then I welcome s/he setting out the tangible and intangible costs and benefits ”…… with due care and diligence” required under Section 37 and emailing his/her analysis to other Strata Committee members."

That initial email also included:

The 50m outdoor North Sydney Swimming Pool is riddled with concrete cancer and will be replaced when Council decides which Capex programme to accept. 

North Sydney Olympic Pool Consultation: Phase 2

“Council is developing a Masterplan for the future development of the Pool complex as the 50m outdoor pool needs replacing. Six options were explored. See latest News below” 

The 50m swimming pool operated by Hornsby Council was totally replaced a few years ago. 

Council moves forward with the replacement of Hornsby Aquatic Centre 

Under an Owner Builder Permit that I rec’d from the Dept of Fair Trading in 2008, I applied a Drizoro Maxseal membrane on top of a large double garage that I had built a few years ago.  The product was expensive.  If you do not meticulously apply the same density membrane sealant, then the membrane is only as protective as its weakest point. 

If you Google ‘swimming pools concrete cancer’, you will receive a very large number of trades people offering to repair your leaking swimming pool. 

It is a well-known fact that water will eventually penetrate concrete and when it does the reinforcing steel in the concrete will rust and expand and eventually crack the concrete  - final two photos.  When the concrete cracks the water above and beside the concrete will penetrate at an increasing speed and materially reduce the structural integrity of the concrete. 

Unlike both Hornsby and North Sydney 50m swimming pools that were in the ground with nothing beneath them except ‘mother earth’, the indoor swimming pool at The Pavilion has a garage underneath it.  Hence, when water leaks into the surrounding concrete, it will eventually rust the reinforcing steel and undermine the integrity of the suspended slab at considerable cost to the Owners’ Corporation.

Philip Johnston's email to the Strata Committee sent 12 April '18 included:

"If you click on : https://www.caselaw.nsw.gov.au/ and then the “Advance Search” tab and type in ‘Strata Committee’ between 01/01/2017 and 01/01/2018, as I have done (in my Caselaw1.jpg Attachment), you will see (at the bottom of the jpg) 55 cases in NSW (in my Caselaw2.jpg Attachment) that went to a tribunal or a NSW Court where a Strata Committee is either an applicant or litigant or a defendant - during the 12 months to 1 Jan 2018. 

I seek to avoid litigation by understanding my legal obligations and adhering to them."

Philip Johnston's email to the Strata Committee sent 16 April '18 included:

"If you Google ‘leaking swimming pool’, you will receive a plethora of threads to companies that profess to be able to repair a leaking concrete pool.  Why?  Because water will eventually leak through concrete, and when it does the reinforcing steel therein rusts and expands which fractures the concrete and thereby accelerates further leakage and destabilization of the concrete – VERY, VERY COSTLY if at all possible to repair when open clearance is required for a carpark.

Due to (i) to (iv) above, I am concerned that the 22 year old swimming pool on Level 6 is leaking which may have already caused material damage to the structural integrity of the concrete slab that separates Level 6 and Level 5."

Philip Johnston's email copied to the Strata Committee sent 18 April '18 included:

"I am prepared to defer this material matter over until to the next Strata Committee meeting, contingent upon members of the Strata Committee that live at The Pavilion taking the time to –

·    inspect the -
i)          stalactites on the roof;
ii)         brown stain on the roof and on vertical concrete pylon; and
iii)         swollen metal bulge under one of the more prominent stalactites,
under the swimming pool; and

·    feel the vertical concrete pylon evident in the below embedded thread:



I do hope that some members of the Strata Committee might know a structural engineer, or at least a civil engineer, that may be prepared to also inspect the above i), ii) and iii) prior to our next Strata Committee meeting."

Philip Johnston's email to the Strata Committee sent 16 May '18 included:

"Would you please read –

a)          my below email to Lauren Cook sent yesterday that requested that item 9 of the Agenda be re-drafted;

b)          Lauren’s below response that noted “It’s too late for me to change it in the agenda now“; and

  c)          my attached email to Alex sent Thu 3/5/2018 11:03 am that explains that I do not want to be included as a Defendant’ in any possible Class Action launched by some of the Owners Corporation as explained in my attached 1st email if water that has leaked from the pool has reduced the structural integrity of the supporting concrete slab.  I refer to Jim Pappas’ below comments from my 1st Attachment:

“The concrete stalactite is caused by any water that penetrates cracks in set (hard) concrete will carry any free calcium hydroxide solution to the edge of the concrete.  Stalactites can form when the solution emerges on the underside of the concrete structure where it is suspended in the air, for example, on a ceiling or a beam. - this may or may not cause the steel within the concrete to start to corrode.” 

I do hope that members of the Strata Committee that reside in Sydney have inspected the brown stains and stalactites –

A.    evident in http://muggaccinos.com/MilsonsPoint/SP/SP.htm;

B.    as requested in my attached email to Veronica Wells sent 17th April 18; and

C.   pursuant to 37 ‘Duty of members of strata committee’ of the Strata Scheme Management Act 2015."

Current Prime Minister, ScoMo, and some readers of the Mosman Daily and the North Shore Times, are aware that North Sydney 50m Pool will shortly close for 12 months to be replaced 'in toto' because the steel in the concrete has rusted out.

Costs incurred this financial year to continue the pool listed in below details on Strata Choice website

Pinnacle Building Consultancy                                    $1,100.00

Eastern Subs Pool Services                                      $13,930.50

RAM Air-conditioning                                                      $430.00

Total                                                                           $15,460.50


Potential new additional cost

Eastern Subs Pool Service has quoted $3,630.00 to supply and install a Rolachem RC9 water filter unit that measures and controls chemical sanitisers and pH levels for a swimming pool