Bridge project needs investigation

Southern Moreton Bay Islands (click to enlarge)

Southern Moreton Bay Islands (click to enlarge)

Many in the community are advocating that a bridge be built linking one or more of the southern Moreton Bay islands (SMBI) to the mainland. Some politicians have indicated support. But many issues need to be considered and questions answered before a bridge project can proceed to construction.

The generally accepted way of developing a major infrastructure project is to divide the project work into phases and require that each phase be completed and approved at a “decision gate” before any more work is done.

Project phases and decision gates

The Federal Government uses four standard phases for developing major transport projects:

  • Project Identification Phase
  • Project Scoping Phase
  • Project Development Phase
  • Project Delivery Phase

If there is any intention to seek Federal Government funding contributions to a bridge to the Southern Moreton Bay Islands then it makes sense to understand and use this four phase approach to project development.

The use of these four phases was discussed in a report titled Best Practice Cost Estimation for Publicly Funded Road and Rail Construction commissioned by the Federal Government.

Below is a discussion about how this four phase process could result in construction of a bridge, if the project is viable.

Project Identification

Weinam Creek Ferry Terminal

Weinam Creek Ferry Terminal

In this initial phase of the project, sometimes called a concept study, the challenge is to:

  • Clarify the project objective
  • Identify alternative ways of meeting the objective
  • Select a preferred alternative that best meets the objective

For the sake of this discussion a project objective could be to provide transport between the mainland and SMBI more safely, reliably and economically than the current ferry/barge service. The project name during this phase could be the SMBI Transport Project.

The project identification phase would consider a range of options which might achieve the project objective. In this case the options might include a bridge as well as different forms of water based transport. At this early stage of the project a wide range of potential solutions should be considered even if they may seem at first to be impractical or uneconomic. Options identified would usually be compared to the current arrangements.

Some cost-benefit analysis should be done to identify who would benefit from the project and estimate the types and amounts of benefit. Costs would include capital and operating costs. Community costs and benefits to be considered might include:

  • Increased economic activity and opportunities
  • Increased use of SMBI land to accommodate more of Redland City’s population growth
  • Changes to quality of life for island residents
  • Improved access for responding to emergencies
  • Environmental impacts e.g. boat strike injuries to marine wildlife

Based on this preliminary work the study team should identify a preferred alternative. For this project it may be a bridge linking one or more of the four islands to the mainland. A capital cost would be estimated which in this case may range from say $200-600 million.

In the project identification phase there are minimal resources available for project investigations. Typically, the study team will use readily available information such as industry standard cost estimates and old study reports such as GHD’s 2011 report on Southern Moreton Bay Islands Water Transport Alternative Route Study.

Analysis during the project identification phase is largely conceptual. Many assumptions will be made which need to be clearly defined so that they can be reviewed and checked in future phases of the project. Any estimates made (costs, revenue, times) are very approximate.

The project identification study report should also suggest the work scope and estimated cost for the next phase.

A project identification study, done to a reasonable standard, would typically take about six months and cost less than $100,000.

Project Scoping

The purpose of project scoping is to investigate specific options that achieve the preferred project alternative. Assuming that the previous phase found a good case for a bridge to be built, this project scoping phase would focus on identifying the best route. During this phase of work the project might get a new name such as the SMBI Bridge Project. Given that there are four inhabited islands and two obvious mainland connection options there are quite a few route alternatives to study.

This phase may include preliminary assessment of:

  • Engineering design and cost estimates
  • Navigation requirements (width and height)
  • Road transport technical requirements
  • Land access
  • Environmental and other regulatory requirements

Community consultation and market analysis would take place to find out the views of residents and property owners on the four SMBI islands about different ways of meeting the SMBI Bridge Project’s objectives.

Preliminary financial analysis of each option will be undertaken to determine a preferred option. This is based on estimates of capital and operating costs as well as revenue. The project would have a long economic life so discounted cash flow analysis is required.

The study report should also produce a plan and budget for the next phase.

Depending on the level of detail required this work might take 6-12 months and cost about $500,000.

Project Development

If the project gets to this stage, often called a feasibility study, it might have a name like the X to Y Bridge Project.

This phase of work is to investigate the preferred option in detail to ensure that it is economically and legally viable. The scope of work might include activities such as:

  • Land access arrangements (easements, lease or purchase options)
  • Environmental impact investigations and approvals
  • Other regulatory requirements (e.g. marine navigation, main roads, town planning)
  • Detailed engineering design for the bridge and connecting roads
  • Cost estimates (capital and operating)
  • Project development and construction schedule
  • Contracting strategy
  • Revenue estimates (if it is to be wholly or partly funded by tolls)
  • Financing strategy (grant funds, debt finance or private sector funding)
  • Risk management plan for the project
  • Financial model of the project
  • Community engagement

It is likely that this phase of the project would take at least 12 months to complete. Its cost might fall within a range from $2.0 million to $5.0 million.

Money spent on this upfront planning and design work will give more accurate cost estimates and reduced project risk during the next phase which is project delivery.

Project Delivery

If the feasibility study finds that there is a financially viable way of developing a bridge, a combination of private and public sector investors may commit to the project.

A project implementation structure is adopted. Funds are made available, contracts awarded and construction work starts. Some things may not go quite according to plan which is why the project estimate usually includes some provisions for contingency. This phase of work might take two to three years to complete.

Overall project schedule

Overall project schedule (click to enlarge)

Overall Indicative Project Schedule (click to enlarge)

In an ideal world one might expect the overall project duration (from first thoughts to completion of construction) to be the sum of the times taken to complete each of the four phases described above. However, we need to remember that a decision is required to commence each phase of work and it can take many months to get funds and other arrangements approved. Reports have to be written, circulated and reviewed. Negotiations are required. This is particularly the case where more than one level of government is involved.

The Overall Indicative Project Schedule illustrated here assumes a standard three months to get each phase approved which is very optimistic and is only likely to happen where a project has political support at all levels of government. If each decision interval were to be a more realistic six months then the project would take another whole year to complete.

Ted Smout Bridge

Ted Smout Bridge (on the left) duplicated the Houghton Highway to Redcliffe

This schedule has a similar overall duration to the project which resulted in construction of the Ted Smout Memorial Bridge linking Redcliffe to Brisbane.

It may be possible to cut some corners and compress such a schedule. This would require strong political support and willingness by funders (government or private sector) to take more risk than is usual for such projects.

Start at the start

There is significant community interest in having a bridge built to one or more of the southern Moreton Bay islands.

To achieve real progress, a project identification study should be promptly initiated, and properly executed. This work would be relatively inexpensive and could be easily funded by the Redland City Council and/or the State Government. The Federal Government does not normally fund work during the project identification phase.

A project identification study report would enable the costs and benefits of a bridge project to be better understood by all stakeholders including the community, governments and potential private sector investors.

Further reading

Russell Island needs a bridge by Rita Brathaug



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5 thoughts on “Bridge project needs investigation

  1. With the Wienam Creek PDA wanting our transport hub and our parking sent off to remote areas so as to have unlimited access to our transport hub ,how about the deal includes bridging access to Russell and cable barges to the others ???? So many islanders would benefit and instead of the Ghetto that is now Russell’s identity, we could lift ourselves out of the grinding stagnation and council induced povety of our islands

  2. If the cost of the Ted Smout Bridge is 315 million for ‘2.7 km the cost to connect for example Russel Island and other Islands will be much cheaper than this.It doesn’t require require 3 Lanes for the start and it does not need to be designed for heavy traffic.Therefore a cheaper version should be not more then 200 Million.A toll system could help to finance it.At the moment there are about 20 000 fares a week to my knowledge with an estimated average of 5$ per trip which totals about 5 million dollar a year. 5 million per year would already serving the interest of 100 million dollar costs.A Public Private Partnership could be set up with tax-saving initiative so there would be not much need from the public.Beside this there are many other advantages of revenues through more income from the tourist industry and others.The Parking area on the mainland could be developed for other purposes and it will be at the end a win win for everybody.A security system could identify possible hoons and they still have to go over the bridge to flee the scene which will frighten them off.Not to forget that the building of a bridge will create employment taxes and the like.Therefore I don’t understand why it is not already on it’s way.An estimated cost per 1km bridge is roughly 100 million dollars( these figures come from the construction industry) but as mentioned these costs are for heavy traffic designed bridges with lots of traffic.The revenues from the tourist industry would be enormous a small bridge even to North Stradbroke Island would boost the whole economy and would give the Redlands a good stable, sustainable income.I don’t think that the politicians had a closer look into this, I believe they more interested to maintain their votes. In on of the plan there is an estimated population of 22 000 on the bay Islands. Of each such person would pay 1000 Dollar a year extra this would be 22 million dollar a year or 8 million with the current population.
    Most of the islanders would be big compensated with their much higher value of their properties.
    All these above will boost the economy and Australia urgently needs investments in these days.

  3. I Didn’t come here to live in the suburbs, I can choose to do that by going back to Brisbane. I love my Island and I don’t want or need your proposed development. The longer people ruminate over this, the longer council will delay providing Island appropriate services( like a high school). If you want all the convenience of mainland living, GO BACK TO THE MAINLAND. Leave Moreton Bay alone.

  4. For the islands to go ahead and have stable economies a bridge is needed sooner rather than later, and as more people move to the islands will the current system cope? whats the max amount of people that the ferry can support per hour at what cost?

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