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Preston No.2 Reservoir
Design, Construction, and Contractual Matters.

Historic Photos of this reservoir are held by University of Melbourne Archives UMA with Location Numbers GPNB/1239, GPNB/1240, and GPNB/1164 to 1183. Several of them are represented here. Global coordinates of the Reservoir, determined through Google Maps are:
-37.72275, 145.00798

The Reservoir.

In 1908 Monash won a contract with the Melbourne & Metropolitan Board of Works to build a large reservoir in the northern suburb of Preston; the second in the locality. Still in use, it resembles a vast swimming pool only partly sunk into the ground. The walls project part-way above the original ground surface. As the walls of this type of reservoir were constructed, earth excavated from the basin was piled up behind them to form embankments. These serve as a second line of containment, and also help the walls resist the outward pressure of the water. However, when the water level is low the inward pressure of the earth is the dominating effect. The walls were therefore designed to resist either outward or inward forces tending to cause tilting or (less importantly) sliding.

Plan of the reservoir. Refer to text above. Cross-section showing wall. Behind it is a bench formed when excavating the bottom of the reservoir. The gap between this bench and the back of the wall is filled with imported earth.

Established practice at the time was to build such walls of mass (i.e. unreinforced) concrete. If sufficiently thick, these were able by their weight alone to resist the tendency to tilt or slide. Monash was aware from the technical literature that the amount of concrete required could be reduced greatly by exploiting the strength of reinforced concrete. A rough calculation showed that, despite the cost of the reinforcement and more complex formwork, a significant financial saving could be achieved overall. The new form of wall comprised a thin vertical plate attached rigidly to a wide base slab. High walls, such as those of Preston No.2, required strengthening at regular intervals with vertical ribs, or 'counterforts'.
More about initial design.

Perspective sketches of a mass concrete wall and a reinforced concrete wall with counterforts. The former is a thick wall whose width decreases linearly from base to top. For the latter, refer to text above.


The Contract.

The Board of the MMBW consisted of 'Commissioners' representing the municipalities that made up the metropolis. Engineering design was normally carried out in-house by its own staff of engineers. Monash had had previous dealings with the MMBW, mainly in the introduction, testing and supply of reinforced concrete pipes for water and sewerage. He had established friendly relations with its 'Designing Engineer' Christian Kussmaul and was a personal friend of Chief Engineer Calder Oliver. Thus, he was aware at an early stage that they were preparing a conventional mass concrete design for Preston No.2. Monash's main contact amongst the Commissioners was George S Walter, who informed him that Members were divided on the issue. Walter was not hopeful, but advised JM to "open the attack, educate the Members, and prepare for a continued fight until [reinforced concrete] is ultimately recognised". He asked for information that would enable him "to do some convincing" himself. These moves proved effective, and the Board decided that tenderers should be allowed to offer a price for an alternative reinforced concrete wall, provided they took full responsibility for its quality and safety.

This gave RCMPC a head start, as most of their competitors were regular contractors with no experience of construction in reinforced concrete and no knowledge of its design. At that time Australia had few independent consulting engineers who could advise them, and only a handful of these had the knowledge and confidence to design the walls required for Preston No.2. Also, Monash was able to find out what assumptions had been made concerning the nature and strength of the earth at the site. This allowed him to prepare a design in reinforced concrete that offered the same degree of safety as the MMBW design, but at a considerable saving in cost.

When the call for tenders was published, the Master Builders Association complained that its provisions were unfair and asked the Board to receive a deputation. Monash got wind of this and wrote to the Board asserting that the adopted format was international best practice. He suspected that the MBA was attempting to have the provision for alternative tenders deleted; but its eventual stance was that the Board's engineers should have prepared a fully-detailed reinforced concrete design alongside the mass concrete one, so that all tenderers could have had an equal opportunity to bid for either or both. The MBA received no reply to its request.
More on MBA and JM.

In submitting his tender Monash added to the MMBW's standard General Conditions of Contract his own specification for the reinforced wall, plus a copy of his computations and drawings, and an explanatory document justifying the choice of reinforced concrete.

According to The Age the lowest tender for mass concrete walls was £31,361. RCMPC's price for reinforced concrete was £26,489, and the Board's Water Supply Committee recommended its acceptance. This advice was discussed at a fiery meeting of the full Board in March 1908 where, despite energetic protests from Commissioners friendly to the Master Builders, it was eventually accepted by majority vote.

At least one rival r.c. design was submitted.

A valid point made by the MBA was that the project was bigger than anything RCMPC had previously tackled and involved commensurate financial risk. The internal dimensions of the reservoir would be 516 × 476 feet in plan, with walls rising 20'-6" above floor level (157m × 145m × 6.25m) Some 80,000 cubic yards (61,200m³) of earth were to be excavated and formed into embankments. There were 8,000 cubic yards of reinforced concrete to be cast in the wall and about 2,300 (1760m³) in the reinforced floor. Structures were required to house the inlet and outlet works.



Although the Board had taken years to decide what size reservoir it could afford - Preston No.2 being about half the size originally hoped for, with plans to build No.3 at some future date - the engineers were now under pressure to produce the reservoir in minimum time in order to catch the winter rains of mid-1909.

E G Ritchie was appointed Supervising Engineer, reporting directly to Oliver and presumably based at Head Office. Under him would be engineer H O'B Shearan with up to a dozen Inspectors. Unfortunately, Ritchie had had no hand in the awarding of the contract and he was not at all enthusiastic about the departure from established practice. He viewed it as "an experiment" and Monash later claimed that his "hostility" had led to awkward relations on site. The situation was further complicated by the desire of the Board and its engineers to ensure that RCMPC retained full legal responsibility for the innovation. When it became evident during the course of construction that modifications were needed, they insisted that the written record show these as originating from RCMPC, even when the idea had come from them. Monash went along with this, writing formal letters proposing the changes which were then agreed to by the Board's engineers.

In contrast, JM must have seen the innovation as a chance to open up new horizons for RCMPC and place the firm on a level with Victoria's major contractors. The project seems to have become his 'baby' during the years 1908-1910. Many sheets of preparatory material are in his own hand-writing: stress calculations; cost estimates; planned rates of earthworks, delivery of materials, and concrete construction. Having calculated from these the rates of cash flow he confidently concluded: "we benefit £600 per month". During construction he prepared analyses of progress; notes on contractual matters; and instructions to subordinates. This preoccupation explains his much lesser involvement in projects concerning bridges, office buildings and warehouses during this period.

General Manager Alex Lynch was provided with the necessary information to check and maintain rates of supply of materials and construction progress. Gibson was informed that the labour force required would be so much bigger than on RCMPC's normal jobs that clerical help would be required on site. Therefore, a capable young man (at 30/- to 35- per week) should be appointed to act as tally clerk, timekeeper, and record keeper - and to give general clerical assistance to Foreman Frederick Bloom, who would be fully occupied with direct supervision. Information on costs would be coming through the normal channels [gangers' time sheets, etc], and therefore the books would be 3 to 4 weeks behind "as usual". Therefore JM wanted approximate reports on expenditure produced promptly, even though they might not be 100% accurate.

Monash decided to appoint as earthworks sub-contractor D J McClelland, having had contact with him in the latter's role as Shire Engineer of Kerang. However, he told McClelland that Oliver would use his extensive powers under the MMBW's General Conditions of Contract to block such an arrangement. It was therefore agreed that McClelland would appear on RCMPC's payroll receiving a salary plus very large bonuses designed to cover his operational costs. As part of the charade, McClelland was obliged to pay his men in RCMPC's name. Not surprisingly, this informal and confidential arrangement made management of the works more difficult and resulted in some friction over payments.


Problems of adaptation.


Fig.1. This photo shows an advanced stage in the earthworks. At left, earth is banked up behind the line of the future retaining wall. Construction has commenced at the far end of the left-hand wall. In the distance, the far wall has been cast, but shuttering (formwork) has not yet been removed. A gap may be seen in the rear wall, permitting access to the interior of the reservoir. University of Melbourne Archives, Reinforced Concrete & Monier Pipe Construction Co. Collection, GPNB/1175.

McClelland started on the earthworks at the end of April 1908, digging material from the centre of the site and piling it up behind the line of the future walls. Progress was initially steady, though he was hindered by the need to leave large gaps in the north and south embankments where the underground inlet and outlet pipes would pass through. The MMBW had placed orders with local foundries for the large valves and connecting pieces, but these still had to be made, and the manufacturers were behind schedule. Ritchie refused to accept that the gaps seriously interfered with McClelland's operations, and pressed Monash for faster progress ahead of the rains.

Just prior to the scheduled start of concreting, MMBW inspectors condemned all the concrete screenings delivered to the site in readiness, on the grounds that they were honeycombed. JM took the opportunity of a temporary absence of Oliver and Ritchie to write an eloquent letter to Shearan arguing that the stones were strong and hard and would adhere to the mortar matrix better than the bluestone specified. He explained that all quarries in Melbourne were in a ring [cartel] and had adopted a take-it-or-leave stance. This meant that RCMPC would be obliged to locate and open its own quarry to meet the requirements of the specification - so could Shearan please approve use of the stones that had been delivered, while other arrangements were made? It appears that JM won this one.

By the end of August it was possible to start casting the foundation slab for a portion of the wall, and then building up the wall itself and its counterforts. The full height was built up in five stages, or 'lifts'.


Fig.2. Building the shuttering for a section of retainin wall. At left are sections of shuttering completed to full height. At right is a section of wall from which shuttering has been removed after the concrete has hardened sufficiently. University of Melbourne Archives, Reinforced Concrete & Monier Pipe Construction Co. Collection, GPNB/1171.

Fig.3. Fig.4.

Fig.3. The back of a typical portion of completed retaining wall, showing the counterforts. Earth will soon be filled against these. University of Melbourne Archives, Reinforced Concrete & Monier Pipe Construction Co. Collection, GPNB/1182.
Fig.4. Sketch showing a section of wall under construction. The footing and two lifts of the face plate and counterforts have been completed. The vertical reinforcement is shown protruding, ready for subsequent lifts. (For simplicity, only a few vertical bars are shown, the horizontal reinforcement in the face plate has been omitted, and the reinforcing cage for the counterforts has been indicated by a few lines.)

Commencement of work on the wall brought home to all concerned that the scheduling of earthworks would have to be modified to suit the new form of construction. A mass concrete wall could be built up gradually over considerable lengths and the earth kept up level with it, without over-stressing it. A reinforced concrete wall works at much higher stresses and its action also depends on the 'bond' or adhesion between concrete and steel. The necessary strength develops slowly - after one week it is about half its full value, and after four it is almost at its maximum. To allow for this, it was necessary to delay the packing of earth behind the wall, and carefully control its rate of placement. Another factor was that for workplace efficiency and quality control, it suited RCMPC to complete a short length of reinforced wall to its full height before proceeding to the next.

Monash had foreseen this. He had mentioned briefly, in his first approach to McClelland, that the earthworks would have to proceed "piecemeal" once wall construction commenced and suggested it might be best to let RCMPC handle this phase. However, McClelland seems to have either forgotten or neglected the warning. The unusual relationship between contractor and sub-contractor can hardly have been conducive to the close integration of operations for which JM later became famous.

For their part, Ritchie and the MMBW Inspectors, responsible for detailed quality control, seem to have been impatient with the rate of progress. They were - as mentioned - under pressure to get the reservoir complete before winter. They were also unhappy that Monash had persuaded Oliver and Kussmaul to omit a vertical sealing layer of fine clay, or 'puddle', normally placed at the back of a mass concrete wall to ensure that it was watertight. (JM had argued that a reinforced wall would be sufficiently watertight without the puddle layer and that its omission would save £400.) Puddle was placed in a wet condition, hence its name, and it seems that initially the Inspectors, unable or unwilling to change their habits, were insisting that the earth fill placed immediately behind the reinforced wall should be of a similar nature. (Both McClelland and JM described it as "slurry".)

More on assurance of watertightness.


The 'Breakaway'.

The result was that earth was piled up behind the new wall too fast and too wet, and on 24 September 1908 a portion of face plate broke away from its counterforts. This must have been a considerable blow for Monash, apparently confirming the views of the conservative engineers and of the MBA and its supporters. He went back to the 'drawing board' to check various ways in which the connection between the face plate and counterforts might have been overstressed.

More technical details.

Copies of his calculations were sent to Ritchie to convince him that the design was in fact satisfactory. At the same time, JM enclosed a lengthy justification of his claim that reinforced concrete walls became watertight, based on experience with his own water tanks. [Link.]

Monash tried to limit the spread of news about the 'breakaway', but soon learned that photographs of it were being circulated and even offered for sale. In an attempt to trace the culprit he politely challenged several prominent figures, including Ritchie, all of whom assured him of their innocence.


The event did make it possible for Monash to obtain an agreement in writing that the rate of placement of earth should be carefully controlled; although as usual he was expected to be the first to raise the matter in writing. Ritchie responded by specifying that no earth fill should be placed against the wall in the first six weeks after construction of the base slab. JM then negotiated a 7-week extension in the time allowed for completion of the project. Another significant result of the breakaway was an agreement to install an agricultural drain at the base of subsequently-built sections of the wall to reduce horizontal pressure by draining moisture from behind it.

The delay caused an interruption to progress payments, and in October Gibson warned Monash that RCMPC was experiencing cash flow problems and would have to get a loan "in the usual quarter" (probably from David Mitchell) to "see them through the day".

The reservoir floor.

In the meantime, work had commenced on casting in situ the 3 inch (75mm) reinforced slabs that were to form the floor of the reservoir.


Fig.5. This photo was taken when construction of the floor was well under way. University of Melbourne Archives, Reinforced Concrete & Monier Pipe Construction Co. Collection, GPNB/1170.


Distortion of the wall.

Early in October 1908, J L Nolan took over from Shearan as the MMBW's on-site engineer. It was about this time that RCMPC workers first reported minor bending of the face plate and of the stiffening beam that ran along the top of the wall. They also observed a slight tendency for the wall to tilt inwards in places due to the pressure of the earth. This inspired a new flurry of computation in Monash's office, continuing into November. Besides going over the detailed arithmetic, he and his assistant engineers, J A Laing and H G Jenkinson, reviewed the assumptions he had made concerning the physical properties and likely moisture content of the earth fill and foundations. The assistants prepared fresh analyses totally independent of JM's. They no longer assumed that the wall would be entirely impermeable and that the earth behind it would therefore be reasonably dry and stiff. Analyses of the worst-case scenarios showed much lower factors of safety against over-stressing and overturning than Monash - and the Board's engineers - had previously calculated.

More technical details.

As the earth was brought up to full level behind the walls, the tilt of several portions increased. Sections where the wall projected least above the original ground surface showed no appreciable tilt, because the overturning effect was small. Furthermore, at these locations the earth beneath the base of the wall had been deeper below the original surface and thus had been compacted by the weight of overlying layers - it was therefore stronger. However, at sections where most tilt occurred, these conditions were reversed: the overturning force was greatest and the foundations weakest. To make matters worse, the foundation material at certain locations was of a clayey rather than a sandy nature and more liable, if wet, to squeeze out when subjected to pressure.

The development of distortion in the wall, and particularly of obvious tilting, must have aroused the fears of the more cautious engineers, and inspired Monash's political opponents, but the issue did not come to a head until later. By December 1908 the earthworks were basically complete.


McClelland, the Board, and RCMPC.

As work progressed, McClelland had found himself in a three-way conflict of interests. To suit the MMBW and its suppliers, he was obliged to work around the gaps in the north and south embankments. To suit RCMPC, he was obliged to hold back the earth filling until sections of wall were built to their full height and allowed to gain strength. However, it would have suited McClelland to complete the earthworks as fast as possible in a single operation. Preston No.2 was not his only contract. He had at least one other in country Victoria, and as work fluctuated at Preston, seems to have shuttled men and perhaps horses between jobs by rail. In an attempt to keep his teams working, he stockpiled earth on top of completed parts of the banks, ready to be tipped into place behind the walls when they had gained sufficient strength, and into the gaps when the MMBW's pipes had been installed. These portions of bank settled under their own weight plus the weight of stockpiled earth, and the MMBW Inspectors demanded constant re-levelling of the upper surface to the specified level, involving McClelland's men in extra, and apparently futile, carting.

As the final touches were put to the embankments, relations with RCMPC became strained. McClelland felt he had a right to extra payment from RCMPC because of the delays and inconvenience caused by the new form of construction. Monash countered that McClelland was a university graduate and experienced engineer, and should have been able to foresee the challenges, organise his operations accordingly, and frame his quotation to suit. RCMPC's Managing Director, John Gibson, became involved and strongly worded letters were exchanged. At one stage, McClelland exploded "I have not got any flying machines to send men to Melbourne at a day's notice", and JM claimed that on one occasion he had "bounced" out of a meeting in "great anger".

Much more.

As regards McClelland's claims on the MMBW for delay and inconvenience, he was officially an 'employee' of RCMPC, and could only ask Monash to appeal on his behalf. However, Oliver denied that the gaps presented any serious impediment to the earthworks and, like Monash, suggested McClelland could have planned his operations better. JM could only promise his sub-contractor that he would do his best for him in negotiations with the MMBW when the contract was wrapped up.

As the shifting of earth neared its end, a new player entered the scene. This was Augustus Wolskel, sub-contracted to RCMPC at the end of January 1909 to supply the asphalt sealant for joints in the floor and wall. An industrial chemist, he insisted on researching thoroughly the optimum proportions of flux and asphalt. When Monash protested that "The delay is very seriously embarrassing us not only with the Officers of the MMBW, but with the progress of the earthwork", Wolskel pointed out that at the end of a major contract there was always haste to get smaller items out of the way but, as the joints were essential to the safety of the reservoir, the job should be done properly.

More details.



On 15 April 1909, with all work complete except for final adjustments to the embankments, water was let into the reservoir for the first time. Ritchie's primary concern was to check the watertightness of the walls. Monash had admitted that there would be some initial leakage but had promised that this would diminish rapidly. Arrangements were made to measure the water flowing from the agricultural drains. The initial leakage was significant - about 10,000 gallons per day. A small inward bulge appeared at one place in the walls, presumably due to a localised defect; but on a more general scale the tilt of susceptible portions of wall increased. The probable cause was that water was seeping into the clayey soil behind the wall and, as in the case of the 'breakaway', increasing its weight and decreasing its stiffness, leading to increased horizontal pressure. An additional effect was to hasten consolidation of the banks, leading to further subsidence - another problem for McClelland.

The maximum water level was reached about 6 May and was maintained until 28th while change in the rate of leakage was observed. The reservoir was then emptied slowly over the next fortnight. Ritchie inspected the walls during this period. With the reservoir dry, it was noted that some of the floor slabs had lifted and cracked, particularly close to the walls.


MMBW versus RCMPC.

Re-filling commenced almost immediately, and the reservoir was placed in service. From the start of June the contract was deemed to have entered the six-month 'maintenance period' during which RCMPC were obliged to fix any problems that might be revealed. In July, Gibson and Monash started pressing Oliver to release the several thousand pounds still owing to RCMPC, withholding only £500 as a deposit or guarantee during the maintenance period. However, Ritchie felt strongly that because of the unconventional nature of the walls and the observed movement, the Board should withhold all further payments until the end of the year. This would mean that some £4,000 would be retained in case major reconstruction or strengthening should be necessary and chargeable to RCMPC's account. Ritchie expressed his reservations in a memorandum to Oliver, who was temporarily absent. The proposal was therefore seen by Kussmaul as Acting Chief Engineer and by the Water Supply Committee, who adopted it. A scheme was mooted in which the tops of dubious sections of wall would be anchored back by steel rods attached to plates buried in the embankments.

To add to RCMPC's troubles, on 16 August their dispute with McClelland was listed for hearing in the Supreme Court (1909 No.573).

By the middle of August the rate of leakage had reduced to half its initial value. A week later, the 17 feet of water in the reservoir was suddenly drained within a period of eight hours. Perhaps intentionally, this subjected the walls to the worst condition they could encounter, with sodden earth exerting its greatest inward force - perhaps even free water behind the wall exerting full hydraulic pressure - and with no counterbalancing outward force from water in the reservoir. It was found that the top of parts of the wall had moved inwards by up to 4 inches (100mm) and that the floor in one corner of the reservoir was cracked and slightly lifted. Surprisingly, a few days later, Ritchie signed a document certifying that the final work carried out by RCMPC had been satisfactory. He later stated that he did this only because he had been directed to do so by Oliver.

On 4 September, the Secretary of the Board formally advised RCMPC that it considered the works had not been "executed in accordance with and in the manner provided by the Contract" and that it did not recognise the last certificate, as signed by Oliver and Ritchie. It intended to make the relevant progress payment, but all other monies would be withheld. Monash was furious. In private letters to Gibson he called the situation a "serious scandal" requiring strong action. "Realising what a strong position we will hold when once we get our hands on this money, and what a weak position we will continue to be in in regard to any tyrannous requirements of the Board until we get that money, I think this is a matter for vigorous action, and at once, as a mere matter of business and not of engineering, to ensure that such an outcry will be made that the Water Supply Committee will certainly deal with the matter at their next meeting." He was confident that RCMPC had supplied the Board with a working reservoir; that its faults were of a minor nature; and that they could be satisfactorily fixed. He was already working enthusiastically on a scheme to use a similar retaining wall for a reservoir at Lovely Banks for the City of Geelong.


Further Assessment.

The Board decided to call in one of Melbourne's leading consulting engineers, J M Coane, to provide an independent assessment of RCMPC's work. From about the middle of September, the reservoir was allowed to start filling again. The Board's engineers kept a careful record of leakage and the position of the walls, revealing further movement, although some sections of wall actually moved backwards. At one stage, the outlets of the agricultural drains were blocked, permitting a build-up of water behind the suspect portions of wall and subjecting them to another severe test. Monash learned through Walter that there was "a great air of secrecy about the whole matter", but that, so far as he could ascertain, the Board did not propose to make any further payments until the end of the maintenance period, except some £200 to £250 for extra works. Oliver was said to be "very much annoyed", but the action had apparently been taken on the advice of Counsel.

The problems at Preston No.2 were reported in the metropolitan newspapers at the end of October - somewhat sympathetically, the deflection of the walls being described as "slight" with "no sign of fracture". However, early in November a Board meeting confirmed the position taken by the Water Supply Committee. On 12th, Ritchie wrote across the face of the last certificate a note declaring it cancelled and withdrawn. The document had not, a that stage, left the MMBW's offices although RCMPC knew of its existence.

In mid-November the water reached full level and was then drained again to allow a close inspection of the interior by both sides to the dispute. The RCMPC party consisted of Monash; Gibson; and Works Manager Alex Lynch. The MMBW party included Oliver and Ritchie; Chairman of the Board W J Carre Riddell; Commissioner Crawcour; and a Mr Pitcher from Fink Best & Hall, the Board's solicitors. Oliver was accompanied by his personal solicitor. Monash recorded in his notes: "The two parties … perambulated the Reservoir in separate groups, not coming into contact with each other". Carre Riddell took snapshots. After everyone except the engineers had left, Oliver and JM toured the reservoir together. JM recorded that Oliver "attributed the bulging of the walls merely to foundation settlement, which was unavoidable, and for which we were not to blame". Oliver said he would specify certain repairs that were needed where localised damage had occurred, and that when these were fixed up he would issue a Final Certificate.

The maximum forward tilt measured at this time was about 1 in 50. Late in November, Nolan told Lynch that a recent text on reinforced concrete referred to a reservoir whose wall had tilted the same way as at Preston. JM guessed the text was Marsh. A modern textbook recommends that the face of retaining walls be built with a backward slope of precisely this amount, to allow for forward rotation. [Smith, 6th edn, p.247.] Mass concrete walls must also have tilted slightly, but because they were built up slowly at the same time as the embankments, the rotation would not have been as noticeable, and the alignment of the top would have been corrected with each increase in height.

Coane also took the opportunity to inspect the reservoir at this time, and was still not satisfied. He was concerned that the floor immediately in front of the toe of the wall appeared to have risen. This suggested that the clay under the toe was not merely compressed, but was being squeezed outwards, thus lifting the edges of the adjacent floor slabs. If this were the case, was there any guarantee that the process would stop? He thought it more likely that the walls would continue to tilt, and that in 10 or perhaps 20 years, they would eventually collapse into the reservoir.

All the engineers were working somewhat in the dark at this stage because the science of soil mechanics was still based largely on the behaviour of coarser-grained sandy materials. It had not yet been realised that when very fine-grained soils (e.g. clays) are subjected to pressure, some of the stress is transmitted through the water, rather than through the clay particles which are thus freer to slide over one another.

The major breakthrough in this respect came in the mid-1920s with the work of Carl Terzaghi, the 'father of modern soil mechanics'.



The opposition to RCMPC from certain Board members was now reinforced by the expert advice of Ritchie and Coane and, no doubt, concern for the public's reaction to images of collapsing walls. Counsel were consulted by both RCMPC and the Board, the latter enquiring whether it was entitled to withhold further payments and to force the firm to rebuild the "unsatisfactory" lengths of wall, or at least to pay for anchoring them back. Either event would have been a serious blow to RCMPC's reputation and finances.

The critical documents were the Board's General Conditions together with the Contract, Specification and Drawings prepared by Monash specific to his reinforced concrete design. The General Conditions applied to any project undertaken for the MMBW. These had evolved to protect the Board against incompetent or unscrupulous contractors who might tie up essential projects for years while legal issues were sorted out. With this aim they gave enormous power to the Board and its Chief Engineer, and not many rights to the Contractor. Responsible and honest contractors signing the document were obliged to place great faith in the fairness and competence of the Chief Engineer.

To legal counsel on both sides, the question of Preston No.2 was straightforward. The General Conditions required that structures be built "true to line and level" as shown on the Drawings. The Drawings showed a wall with a vertical face - the face as built by RCMPC was not everywhere vertical. Therefore the Contract had not been fulfilled. Further, RCMPC's counsel advised that the certificate stating the work to be satisfactory was not a Final Certificate to wind up the contract. He felt that the firm's only hope was to rely on a requirement in the General Conditions that the Board accept the decisions of its Chief Engineer.



We shall never know what the courts would have ruled, because the Board decided to take the intermediate, and less costly, step of going to arbitration. Most engineering contracts allow for the appointment of an independent Arbitrator (or Arbitrators), the selection of suitable persons often being left to negotiation between the parties should the need arise (e.g. Fyansford Bridge). The MMBW's General Conditions allowed no choice. The sole and only Arbitrator for any MMBW contract was its own Chief Engineer. This had worked well in the past. It was said that out of some 100 cases heard to date, the Arbitrator had ruled in favour of the Board in all but two. A somewhat comical situation thus developed in which Oliver as Arbitrator was required to rule on his own actions as Chief Engineer. The Secretary of the Board wrote formally to tell him that a dispute existed and ask him to call the parties together.

A few days before the Arbitration commenced, Monash, Gibson and McClelland managed to reach an out-of-court settlement of their dispute over payment for the earthworks.

The Board's solicitors were Fink Best & Hall, represented at the Arbitration by Mr Fink. Monash himself put RCMPC's case. Gibson was present throughout, but did not speak. Normal legal procedure was followed quite closely, though some informality was accepted. Ritchie and Coane were examined and cross-examined at great length. Nolan, Chief Inspector Randall, Alex Lynch and an RCMPC ganger were called as witnesses. A court reporter was present to make a verbatim transcript, though some asides were not recorded. Despite the strange circumstances, arguments on both sides were put forcefully, effectively and at length: six sessions were held between 11 February 1910 and 8 March, most with morning and afternoon sittings.

The Mr Fink in question is almost certainly Theodore Fink, a notable Melbourne public figure, but I have not yet found confirmation. ADB Online

It was agreed at the start that details of proceedings should not be revealed to the press. Monash made it clear that RCMPC appeared under protest. He argued that the Board was in fact in dispute with its Chief Engineer, not with the firm: Oliver had fulfilled his contractual duties regarding RCMPC so there was nothing more to be said between them. If the others insisted on proceeding, he would put RCMPC's case, but without prejudice to any future proceedings in court. Monash's objections were noted, but the arbitration continued.

Fink asked Oliver to put out of his mind the opinions he had formed as Chief Engineer. The Board considered RCMPC wholly responsible for the fact that the wall was not in accordance with the specifications. The General Conditions placed all responsibility on the Contractor and RCMPC's specification and other addenda reinforced this. Fink spelled out chapter and verse from these documents. Monash had warranted the reinforced concrete work to be "permanent" and watertight. The General Conditions required that it be carried out to exact form and dimensions as shown on the drawings. The Contractor was obliged to correct any defects that arose prior to the expiry of the Maintenance Period at the end of 1909.

Monash pointed out that Oliver had declared the reservoir adequate to do its job, even though not perfect. Under the terms of the General Conditions, the Board was obliged to accept the decision of its Chief Engineer. The reservoir was in service. Its walls had stopped moving and would remain in position. The quantity lost through leakage was now a quarter of what it had been, and was less than that lost from evaporation. Perfection was unknown in the real world of engineering. RCMPC did not hold full responsibility for the wall as built. He had re-engineered the wall designed by the Board's engineers, ensuring that his version had the same factor of safety. He had made the same assumptions concerning the nature of the earth fill and the foundations. He admitted that in doing so he had made the same "error of judgement" in overestimating the strength of the expanding yellow clay on which the tilting sections of wall rested. However, the Board's engineers had selected the site and the contractor was obliged to build on it. Monash argued that RCMPC was entitled to receive the Certificate that had been prepared and signed by Ritchie and Oliver declaring the work satisfactory. RCMPC should be paid the £4096 still owing to it.

In the ensuing arguments over the extent of the Contractor's responsibility, both sides drew on legal precedent, leaning heavily on Hudson's text on contracts in building and engineering. Technical argument centred on the significance of the remaining leakage, and the possibility that further tilting would occur and cause collapse. Monash disputed Coane's pessimism. MMBW staff introduced a new allegation that the concrete in the wall had been very poorly compacted, leaving large voids - though some of the examples they gave had little to do with compaction.

Technical disputation between Monash and Coane was civil and fairly equally balanced. Under questioning, Coane denied any prejudice against reinforced concrete, but came across as more conservative in outlook than JM. In contrast, Monash's questioning of Ritchie generated some heat, leading Fink to accuse JM of "animus". Fink also criticised Monash for basing his defence more on legal, rather than technical arguments. He declared it strange that Monash had not called an independent expert witness to back his views, as the Board had done in calling on Coane.



Throughout the arbitration period Monash had been overseeing the operations of both RCMPC and SARC, with bridge and building projects in full swing in Victoria and South Australia, making at least one visit to Adelaide. Other projects included the Ballan dam, tenders for an Ocean Wharf at Adelaide, and helping a Shire Engineer with hydraulic calculations concerning a pipeline. At the same time he had been involved in detailed planning for his forthcoming expedition to the UK, Europe, and the USA. There was some urgency to complete proceedings before his scheduled departure, which took place about 23 March 1910. He left without knowing Oliver's decision.

On 7 April, the press reported that the Arbitrator had ruled the Chief Engineer correct in accepting the work as satisfactory. RCMPC was to be paid in full. The costs of arbitration (£99/7/3) were to be split between the parties, each side bearing its own costs. No-one could have been surprised. The Water Supply Committee recommended that this decision be accepted as final. The June meeting of the Board was described in the newspapers as "stormy". Commissioners questioned Oliver's competence, and one asserted that he should be fined £100, but it was pointed out that Mr Irvine KC had advised there were no grounds for contesting the Chief Engineer's decision. There were belated demands that the General Conditions be changed to specify arbitration by a three-member panel, or a totally independent person.

It seems that Gibson's letter informing Monash of the result did not reach him until he was in London in August. He declared that it brought great comfort. "Doubtless with the best of motives, my office staff have bothered me with very little detail, but on several occasions their letters have been so short and formal and couched in such constrained, reserved language that their effect was to create a feeling of great alarm that things were not going normally. However, all that has been removed by the good news that Preston has paid, and by cable that the volume of new business booked in Victoria since I left up to August 10 now exceeds £20,000. That should help to keep body and soul together till I return and get my teeth into things again."

Despite the anxiety over wall movement, and lesser concerns over leakage and initial embankment settlement, Monash seems to have been satisfied with the outcome of the project. As mentioned above, he had proposed reinforced concrete walls for a reservoir at Lovely Banks near Geelong. This was to be circular in plan and founded on rock - which would have avoided the major problems experienced at Preston No.2. To reduce cost, he had proposed dispensing with a concrete floor and simply sealing any open joints in the rock. In May 1912, when Professor Payne of the University asked him for a brief CV for his card index, JM listed under the heading of "Reinforced Concrete" only the Benalla Bridge, the Janevale Bridge, Preston Reservoir No.2, and "Numerous Industrial Buildings". RCMPC prepared draft schemes for similar but smaller reservoirs at Oakleigh (October 1911) and Nhill (October 1913). Again, in May 1914, JM included Preston as an example of RCMPC's wide experience of reservoir construction in proposing the use of reinforced concrete for Naval Oil Fuel Stations in Sydney.

Ritchie remained unconvinced of the safety and serviceability of the reservoir and may have covered RCMPC's 3-inch thick reinforced floor slabs with a 6 inch coat of mass concrete, the traditional type of floor. The Preston No.3 Reservoir, completed in 1913 and slightly larger than No.2, has mass concrete walls. In 1921-22 the UK Institution of Civil Engineers published a paper by Ritchie in which he described the application of reinforced concrete at No.2. He stated that "its use is not desirable" - its main disadvantage being the difficulty of integrating wall construction and earthwork. He also mentioned that parts of the wall were founded on "natural yellow puddled clay" which expanded and contracted, causing increased cracking.

RCMPC's tender to supply reinforced concrete walls for the Lovely Banks reservoir was unsuccessful.

Reminder. Like most histories on this website, the account given above is based almost entirely on the extant records of RCMPC. I have not yet made any attempt to search for MMBW records concerning this project, particularly the interesting question of how the wall performed over the years and whether its top was anchored back, as proposed.