NAMBUCCA SHIRE COUNCIL

 

 

Ordinary Council Meeting - 12 December 2012

 

LATE AGENDA                                                                                        Page

 

           

 

  

5        Notices of Motion

5.1     Notice of Motion - Water Supply Steering Committee - Cancellation of January 2013 Meeting (SF844)       2  

9        General Manager Report

9.8     Scotts Head Caravan Park - New Concept Plan in Response to Submissions......................... 3

10      Assistant General Manager Corporate and Community Services Report

10.16  Addendum Report Item 10.12 DA2012/011 346 Residential Subdivision - Bellwood. Update on Assessment....................................................................................................................................... 8

11      Assistant General Manager Engineering Services Report

11.7   Amended Report on Weekes Bridge Reconstruction - December 2012................................. 11    

 


 


Ordinary Council Meeting                                                                                             12 December 2012

Notice of Motion

ITEM 0.0      SF1714            121212         Notice of Motion - Water Supply Steering Committee - Cancellation of January 2013 Meeting (SF844)

 

AUTHOR/ENQUIRIES:     Rhonda Hoban, Councillor         

 

Summary:

 

At its 30 August 2012 meeting Council resolved on the motion of Cr Ainsworth:

 

“That initially meetings for the Water and Sewerage Projects Steering Committee for the Bowraville Off River Water Storage be conducted on a monthly basis.”

 

Council has held its December 2012 meeting and the dam site will be closed over the Christmas period so it is unlikely that there will be any progress to report by the 9 January 2013.  For this reason it is recommended that the January meeting be deleted and the next meeting held in February 2013.

 

 

 

Recommendation:

 

That Council waive the requirement for a monthly Water and Sewerage Steering Committee meeting for the month of January 2013.

 

 

 

 

 

Attachments:

There are no attachments for this report.      


Ordinary Council Meeting                                                                                             12 December 2012

General Manager's Report

ITEM L.1      SF382              121212         Scotts Head Caravan Park - New Concept Plan in Response to Submissions

 

AUTHOR/ENQUIRIES:     Michael Coulter, General Manager         

 

Summary:

 

In response to the recommendation to this Council meeting, the Trust has submitted a revised plan which they believe addresses most of the issues raised in the submissions.

 

 

Recommendation:

 

1.       That the amended Option 3A be placed on public exhibition for the remainder of December 2012 and all of January 2013 and in the interim Council staff assess its parking and traffic implications in consultation with the Trust in an endeavour to put an agreed concept plan to Council’s meeting on 28 February 2013

 

2.       That Council note that the Scotts Head Reserve is now part of the North Coast Accommodation Trust and that the Scotts Head Reserve Trust has been dissolved.

 

 

OPTIONS:

 

There are many potential options.  Council can choose to continue to negotiate with the Trust to try and achieve an agreed outcome for the redevelopment of the caravan park and surrounding Reserve.  Alternatively Council can choose to reject the options which have been put forward and refer to its previous support for the Master Plan.

 

DISCUSSION:

 

In response to the recommendation to this Council meeting, the Trust has submitted a revised plan which they believe addresses most of the issues raised in the submissions.  This plan is a circularised document (colour) to councillors and has also been attached so that it can be downloaded from Council’s website.  The trust has summarised the changes as follows:

 

1.       The majority of the eastern part of the holiday park now reverts to day use area

2.       The road through the day use area is relocated to enhance the functionality of space

3.       The Town Green connection to the eastern day use area is enhanced with a widened area along Short Street

4.       Vehicular access to the holiday park and the day use area are separated

5.       Public access from the Town Green to the beach can be maintained, but not formalised

 

In response to the plan recommended by myself to this meeting, the Trust has responded advising as follows:

 

“The proposal to replace 7 cabin sites and 5 prime camping sites close to the beach with an additional 8 sites in the leased area is not financially viable.  The 5 camping sites alone will yield more that the additional 8 sites in the leased area.  However, the Trust recognises that the eastern area of the reserve is a priority for the community and accepts that trading the additional 8 sites in the leased area of the reserve will reduce the loss of income, as long as the lease fee of $20,000 is maintained.  The alternative option of the Trust maintains the level of cabin accommodation which will enable revenue to grow and development of the reserve to proceed.”

 

A copy of the Trust’s letter is attached.

 

Council staff would like to check on the constructability of the proposed car park and the traffic/pedestrian implications of having through traffic to the beach passing through the proposed car park.  Council should satisfy itself that the proposed car park will have no impact on the existing melaleuca trees.  There also needs to be an assessment in relation to the loss of street parking in Short Street as a consequence of the second access.  This street parking is used by shop patrons.

 

The proposed siting of the 3 cabins against a section of dune which is subject to coastal erosion has been discussed with the Trust.  The Trust is proposing to put in place an engineering solution to the on-going coastal erosion in the event it threatens this section of the Reserve.  However “worst case” is that the proposed 3 cabins can be relocated if the erosion cannot be controlled.

 

It is proposed that the revised plan be placed on public exhibition until the end of January, during which time Council staff will assess the impact of the proposed car park and new entrance to the Holiday Park.  The deferral will also provide time for Council staff to consult with the Trust as to whether other options in relation to access and parking could provide better outcomes.

 

Council has also been requested to note that the Scotts Head Reserve is now part of the North Coast Accommodation Trust and that the Scotts Head Reserve Trust has been dissolved. Whilst this in no way impacts on current matters, any future reference to the Trust should be to North Coast Accommodation Trust.

 

CONSULTATION:

 

There has been consultation with the North Coast Accommodation Trust and Council’s Manager Technical Services.

 

SUSTAINABILITY ASSESSMENT:

 

Environment

These have been previously reported on.  The only concern in relation to the proposed Option 3A would be relation to any impact the proposed car park may have on the existing melaleuca trees.

 

Social

There is considerable community interest in the redevelopment of the caravan park and the reserve area.

 

Economic

The Caravan Park is an important part of the economy of Scotts Head.

 

Risk

The risks are discussed in the report.

 

FINANCIAL IMPLICATIONS:

 

Direct and indirect impact on current and future budgets

 

The proposed contribution by the Trust to drainage, landscaping and maintenance has been previously reported on.

 

Source of fund and any variance to working funds

 

There is no impact on working funds.

 

Attachments:

1View

32419/2012 - Scotts Head concept plan option 3A - Dec 2012

0 Pages

2View

32420/2012 - Letter explaining Option 3A

0 Pages

  


Ordinary Council Meeting - 12 December 2012

Scotts Head Caravan Park - New Concept Plan in Response to Submissions

 


Ordinary Council Meeting - 12 December 2012

Scotts Head Caravan Park - New Concept Plan in Response to Submissions

 


 


Ordinary Council Meeting                                                                                             12 December 2012

Assistant General Manager Corporate and Community Services Report

ITEM 10.16  DA2012/011      121212         Addendum Report Item 10.12 DA2012/011 346 Residential Subdivision - Bellwood. Update on Assessment

 

AUTHOR/ENQUIRIES:     Greg Meyers, Assistant General Manager - Corporate and Community Services         

 

Summary:

 

Council has received a response from Geoff Smyth Consulting on behalf of the applicants for the above Development Application with respect to the recommendations contained within the report.

 

The response was only received late Tuesday 11 December 2012 and this late report is in response to the proposed alternative resolutions outlined in the letter from Geoff Smyth Consulting, in particular:

 

1. That Council resolve that the JRPP be requested to include a condition that Marshall Way be

extended as part of the Nambucca Gardens Estate residential subdivision.

 

2. That the construction be funded by Nambucca Gardens Estate and a Planning Agreement be

entered into for Section 94 contributions to be directed to Nambucca Gardens Estate until the

construction cost is reimbursed.

 

3. That a separate Development Application be prepared for the Council owned section of the

Marshall Way extension.

 

Whilst it is considered that Council is not making a “Planning Decision”, Council may choose to treat it as one and have votes recorded accordingly.

 

 

Recommendation:

 

1        That Council note this report on the assessment progress for DA 2012/011

 

2        That Council concur that the “link” road is a critical component of the proposed development and must be part of the application assessment and consideration.

 

3        That Council authorise the General Manager to provide land owner approval on behalf of Council for Lot 75 DP 832082 being used for the “link” road and assessed as part of DA 2012/011 and access to the site by the proponent and their consultants for the purposes of undertaken the required environmental assessments.

 

4        That in the event that DA 2012/011 is approved by the Northern Joint Regional Planning Panel and the construction of the “link” road is required by the consent, Council authorise the proponent and their approved contractors to enter upon the land to construct the road and ancillary works as required and in accordance with the construction certificate issued for the road.

 

5        That in the event that DA 2012/011 progresses to a recommendation for approval by the Northern Joint Regional Planning Panel, a condition be applied regarding the acceptance of dedication of all reserve areas as follows:

 

Prior to the release of a construction certificate for the first stage of subdivision works, a detailed and site specific Environmental Management Plan (EMP) is to be endorsed by Council. The EMP is to be prepared by a suitably qualified person/consultant in consultation with the Office of Environment and Heritage for the ongoing management, maintenance, weed management, bushfire management and rehabilitation of the entire reserve areas proposed to be dedicated to Council. Further, that the proponent is to implement the EMP from commencement of subdivision works up to the dedication of the reserve areas. Dedication shall occur upon registration of the final subdivision stage of the development. Further, prior to the release of the subdivision certificate for the final stage of development, a monetary contribution to the ongoing management of the reserve areas shall be made to Council based on the costs to undertake the following 5 years management regime (5 years from dedication) outlined in the Environmental Management Plan.

 

6        That Council determine if it wishes to make any representations to the Northern Joint Regional Planning Panel at the determination meeting if the Consultants are satisfied with the additional information required from the applicant to address the matters outlined in the submissions and referrals form the Government Agencies.

<Enter recommendation(s)>

 

 

OPTIONS:

 

There are several options available to Council however is Council is prepared to accept the representations from the Applicant then the following three (3) resolutions could replace recommendations

2, 3 & 4 above

 

2        That Council consider a Voluntary Planning Agreement being prepared and submitted by Nambucca Gardens Estate for the construction of the link road.

 

3        That in the event that the Voluntary Planning Agreement is agreed to between the parties the construction of the link road link road proceed pursuant to State Environmental Planning Policy (Infrastructure) 2007 identifies road infrastructure as a development permitted without consent. Clause 94 of SEPP (Infrastructure) 2007 with an Environmental Impact Assessment (EIA) being completed addressing the Threatened Species Conservation Act and the Environment Protection & Biodiversity Act

 

4        That in the event that DA 2012/011 is approved by the Northern Joint Regional Planning Panel and the construction of the “link” road is undertaken pursuant to a Voluntary Planning Agreement, Council authorise the proponent and their approved contractors to enter upon the land to construct the road and ancillary works as required and in accordance with the construction certificate issued for the road and the terms of the Voluntary Planning Agreement.

 

 

DISCUSSION:

 

This report was scheduled for consideration at the 29 November 2012 Council meeting. However, following representations from the applicants, the matter was deferred to this meeting to provide opportunity for the applicants to consider the recommendations contained in the report and respond.

 

Geoff Smyth Consulting responded on behalf of the applicants which was received by Council late Tuesday (yesterday) afternoon 11 December 2012. A copy of the letter was circulated to Councillors via email Tuesday evening to provide an opportunity for Councillors to digest the response. The response proposes three alternative resolutions relating to the link road in lieu of recommendations 2, 3 & 4 outlined on page 156 of the 12 December 2012 business paper.

 

The recommendations are repeated below in italics and a comment is provided for each one.

 

1. That Council resolve that the JRPP be requested to include a condition that Marshall Way be

extended as part of the Nambucca Gardens Estate residential subdivision.

 

This alternative recommendation is not supported as it is not practical to impose a condition of consent which is subject to a later consideration or Development Application.

 

This is the very matter which Nambucca Shire Council was criticised for in the Land and Environment Court for a Scotts Head development.

 

 

2. That the construction be funded by Nambucca Gardens Estate and a Planning Agreement be

entered into for Section 94 contributions to be directed to Nambucca Gardens Estate until the

construction cost is reimbursed.

 

The proposed Voluntary Planning Agreement (VPA) presented by Geoff Smyth Consulting on behalf of the applicants is one way to ensure the link road is constructed and subject to the lodgement, exhibition and acceptance of the VPA, this recommendation is supported.

 

3. That a separate Development Application be prepared for the Council owned section of the

Marshall Way extension.

 

As the construction of the link road is a permissible land use over Lot 75 and is proposed to be dedicated as a Public Road, State Environmental Planning Policy (Infrastructure) 2007 identifies road infrastructure as a development permitted without consent. Clause 94 of SEPP (Infrastructure) 2007 is repeated below.

94   Development permitted without consent—general

(1)  Development for the purpose of a road or road infrastructure facilities may be carried out by or on behalf of a public authority without consent on any land.

 

Therefore, it is suggested that an Environmental Impact Assessment (EIA) be completed addressing the Threatened Species Conservation Act and the Environment Protection & Biodiversity Act. It being noted that the proponents for the subdivision have undertaken significant EIA work in the area.

 

A revised

CONSULTATION:

 

Applicants and applicants Consultant

 

SUSTAINABILITY ASSESSMENT:

 

Environment

 

Not applicable refer to Item 10.12 in business paper

 

Social

 

Not applicable refer to Item 10.12 in business paper

 

Economic

 

Not applicable Item 10.12 in business paper

 

Risk

 

There is some risk with requiring a consent condition without considering the matter first.

 

FINANCIAL IMPLICATIONS:

 

Direct and indirect impact on current and future budgets

 

N/A

 

Source of fund and any variance to working funds

 

N/A

 

Attachments:

There are no attachments for this report.  


Ordinary Council Meeting                                                                                             12 December 2012

Assistant General Manager Engineering Services Report

ITEM 0.0      BR-BV-2           121212         Amended Report on Weekes Bridge Reconstruction - December 2012

 

AUTHOR/ENQUIRIES:     Paul Gallagher, Assistant General Manager - Engineering Services         

 

Summary:

 

At the Council meeting held on 27 September 2012 Council resolved the following on Weekes Bridge:

 

1        That Council defer this matter:

 

a)      pending a report from the AGM Engineering Services relating to the full costing of all the risk management strategies required for a single lane bridge

b)      that consideration be given option 10 in the report which relates to Eungai Bridge

c)       the report include any other safer options for a single lane bridge

d)      the report include information regarding the alleged use of an outdated Australian Standard used by Council staff

e)      a further onsite inspection be conducted at a daytime Council meeting for Weekes Bridge, Eungai Bridge, Deep Creek Bridge and Congarinni Bridge.

 

2        That Council bring forward one or more single lane bridges within the bridge replacement program currently classified condition 4 or 5 up to the value of $325,000.00 in which the components for Weekes Bridge can be used with the final decision on these bridges being based on the completion of the condition assessments.

 

The latter resolution from Council means that there is no funding available within this financial year for Weekes Bridge as the budget allocation has been reallocated to another bridge. The expenditure to date on materials for Weekes Bridge has now been credited to the new project.

 

This decision enabled the bridge gang to continue working on another bridge project, allows Council to maintain a balanced 2012/2013 budget by not drawing on general funds or at the detriment of other infrastructure projects. This also provides an opportunity to amend the bridge replacement program for consideration by Council in the 2013/14 financial year (or beyond) for either a single or two lane bridge.

 

This report provides a response to information requested by Council and ongoing correspondence from residents.

 

Items referred to in the report to Council on 27 September 2012, which is attached for information, will not be revisited again in this report.

 

Taking into account the financial, social and risk implications, Council needs to consider and determine:

 

1        The level of service to be provided for this community, and

2        The level of acceptable risk relating to a single or two lane bridge at the Weekes Bridge site.

 

 

Recommendation:

 

That Council determine whether a single lane or two lane bridge is to be constructed at the Weekes Bridge site taking into account the level of service to this community, financial, social and risk implications.

 

 


OPTIONS:

 

1        Receive and note the report.

2        Consider funding for Weekes Bridge in the development of the 2013/14 financial year (or beyond) as a single lane bridge.

3        Consider funding for Weekes Bridge in the development of the 2013/14 financial year (or beyond) as a two lane bridge.

4        Fund the difference in costs through review of the bridge replacement program.

5        Bring forward funding from the final year of the Roads To Recovery grant (R2R) which effectively will delete a road rehabilitation project from the final year, will result in a shortened R2R program and adversely affect the condition of the road network.

 

 

DISCUSSION:

 

The community continues to express their opposition to Weekes Bridge being replaced with a single lane bridge. Council has previously acknowledged that community consultation was not undertaken with regard to the reduction in service level to this community.

 

Council’s resolution emanating from 27 September 2012 stated:

 

          “That Council bring forward one or more single lane bridges within the bridge replacement program currently classified condition 4 or 5 up to the value of $325,000.00 in which the components for Weekes Bridge can be used with the final decision on these bridges being based on the completion of the condition assessments” has been enacted.

 

This resolution means that the funding for Weekes bridge has been reallocated and is no longer available within this financial year. Council now has the opportunity to consider the level of service and funding in the 2013/14 financial year (or beyond) for either a single or two lane bridge.

 

Resolution 1 (a) and (c) - full costing of all the risk management strategies required for a single lane bridge any other safer options”

 

The consideration of reducing the bridge to one lane was provided to Council at the meeting held on 12 May 2011 when Council considered the Draft 2011/12 Management Plan and Budget and the General Manager reported the following:

 

“To present a balanced budget, Council’s management is recommending the deletion or deferral of most new “bids” and some significant reductions and reallocations in existing programs.  It is an austerity budget……..The major changes which are recommended by Council’s management to the initial draft budget are as follows:

 

Item 6:  The planned replacement of Weekes Bridge on South Arm with a single lane structure instead of a two lane structure (the existing bridge is 2 lane).  This is a reduction in service level and will provide a saving of $150,000.”

 

Historically, Council has reconstructed bridges ‘like for like’ at a similar standard to the one being replaced with consideration to improving the level of service where possible.  It should be noted that using the current standards bridge decks are generally wider for both single and two lane bridges. Due to the changed economic climate conditions faced by Council, and in this instance, at short notice, the constraints of the budget preparation (as reported), a decision was made to reduce the standard and level of service of Weekes bridge to save a net value of $150,000.

 

It is acknowledged in normal circumstances that the reduction of levels of service would be justified by detailed analysis and community consultation. In this instance the decision to reduce the bridge to a single lane emanated from a financial basis to present a balanced budget to Council as the General Fund is being "squeezed" on the revenue side by rate pegging and on the cost side by depreciating infrastructure which has to be renewed and replaced in a timely way.

 

A technical review has been undertaken to address the issues raised by the community around the safety and risk of a single lane bridge. The report to Council on 27 September 2012 advised that there are risks associated with the reduction in the bridge width to single lane which can not be eliminated but can be managed in accordance with Australian Standard 1742.2 (2009) Uniform Traffic Control devices and AustRoads Rural Road Design Guide (ARRDG). Council therefore must decide on what level of service and risk is acceptable compared to the cost and social implications of its decision and the community’s request that Council replace the bridge in the same location and width (two lane bridge).

 

As previously advised, the estimated cost for the budget on Weekes Bridge was reduced by a net value of $150,000 and did not include the additional costs, detailed below, to implement the signage and line marking for a single lane bridge:

 

·      An amount of $5,080 for signage and line marking to denote the single lane bridge is required in addition to the budget allocation. Works are often undertaken to coincide with other programmed works, and it was planned to reseal the section of pavement up to the hall once the bridge was completed in which the line marking could be included as part of the sealing costs.

·      An amount of $6,000 in addition to the budget allocation is required for excavation of the bank for use within the side track and to increase sight distance.

·      Ripple bars were considered for the road surface before the curve on the eastern approach and discounted due to ongoing maintenance.

 

The community have raised their concerns through correspondence, addressing Council through the public forum and at a site meeting held at Weekes Bridge.  The community believe that a single lane bridge will create a safety issue based on the inadequate sight distance to the approach of the bridge and the potential risk of a collision on the bridge

 

A speaker to the public forum made comment along the lines of "the risk of loss of life (in the event of an accident) makes the risk unacceptable" and the principle known as ALARP (As Low As Reasonably Practicable) surrounding the assessment of the risk at Weekes Bridge. It has been reported and recognised that there is an element of risk associated with the reduction of the bridge width to that of a single lane.

 

Risk is often expressed in terms of a combination of the consequences of an event and the associated likelihood of occurrence (refer AS/NZS ISO 31000:2009).  This is also the definition from the old AS4360.  An important aspect of risk analysis is to evaluate the consequences of a particular event occurring with the likelihood of that event occurring.

 

The likelihood of an occurrence needs to be considered with any assessment of risk, even in a situation where there is potential for loss of life or serious injury.  The mere fact that such a consequence is possible does not itself make the risk unacceptable, but the likelihood of this consequence needs to be taken into account. If we were to accept the philosophy that the consequence of loss of life makes the risk unacceptable we would not walk across a road, drive a car or fly in an aircraft.  There will always be the risk of loss of life or serious injury associated with any of these activities; however we make an assessment that due to the low likelihood of this occurring we deem the risk to be acceptable.

 

With many risk assessments there will be a level of residual risk.  The issue is to determine what is an acceptable level of risk and often this comes down to subjective issues and ultimately in this case that will be a matter for Councillors to determine.

 

All drivers are required to drive to the current road conditions and standard signage is used for warning motorists across Australia to alert infrequent drivers to such locations. In terms of a single lane option in this locality, the following measures will not eliminate, but manage the risk based on the vehicle movements:

 

·      Line marking and signage as recommended by AS1742.2-2009 Clause 4.6.2.2(a)(i) and (ii)

·      Reduce the speed limit for 500 metres before and after the bridge to 60 km/h.

·      Install REDUCE SPEED ONE LANE BRIDGE AHEAD signs on both approaches.

·      Resurfacing of the road would ensure the friction factors are at or above those assumed in the ARRDG stopping distance calculations.(Note: It was intended to complete a reseal of the pavement once the bridge and abutments were completed, this is separate funding under the reseal program)

 

Putting the funding parameters aside, there is a level of risk to Council for a single lane bridge which can be managed and therefore allows consideration for the option of a single lane bridge at this site. The construction of a two lane bridge will lessen the risk; however an element of risk will always remain due to the terrain and drivers not travelling to the conditions.

 

Another factor to consider, particularly for very extreme consequence events such as a dam failure, building collapse etc., is the principle known as ALARP (As Low As Reasonably Practicable).  For a risk to be ALARP it must be shown that the cost involved in reducing the risk further would be highly disproportionate to the reduction in risk achieved. This principle arises because infinite time, effort and money could be spent on the attempt of reducing a risk to zero. In the case of this bridge the construction of a two lane bridge would be consistent with the ALARP principle as it would further reduce, but still not eliminate, the residual risk.

 

Resolution 1 (b) - that consideration be given option 10 in the report which relates to Eungai Bridge”

 

The report to Council on 27 September 2012 included funding options for Weekes Bridge encompassing the consideration to replace Eungai Bridge with a single lane bridge with a caveat that this option would be subject to consultation with the Eungai community.

 

A meeting was held with the Eungai community on 28 November 2012.  This was attended by 24 people, of which 20 were locals from the Eungai community and environs. The majority of the attendees were resolute that their preference is for a two lane bridge and the community would only consider a single lane bridge if a pedestrian access was attached or constructed adjacent to the bridge due to the close proximity of the sports field and recently constructed playground.  This is not economical due to the cost of redesign and manufacture of the prefabricated deck units used on Council bridges.

 

Therefore a two lane bridge is recommended based on the highway works which potentially will remove access to the highway at Eungai and require localised traffic to use the link between the villages of Eungai Rail and Eungai Creek.  Council has provided funding in the current budget to construct a two lane bridge at Eungai.

 

Resolution 1 (d) - the alleged use of an outdated Australian Standard used by Council staff”

 

The reference to outdated standards is orientated at the old and new Austroads guides used by Council and not related to Australian Standards as per the resolution.

 

Austroads guides are not mandatory standards and are guidelines used within the industry. These guidelines are constantly being revised and Council keep abreast where possible on the changes through notifications from Australian Road and Research Board (ARRB) and the attendance at seminars and workshops.

 

The following changes have been made in the 2010 Guide to Geometric Road Design, Section 5 – Sight Distance:

 

Reaction Times

 

The earlier edition of Austroads classified reaction times as 2 seconds - absolute minimum, 2.5 seconds desirable. The explanatory notes say that while there is a wide range of results from research, 2.0 seconds is allowable on difficult terrain where drivers will generally be more alert and where extra signage and line marking is in place.

 

The current edition (October 2010) clarifies the matter by suggesting reaction times ranging from 1.5 to 2.5 seconds for various road conditions. The 2.0 second reaction time is listed as suitable for the following road conditions:

 

·           Higher speed urban areas

·           Few intersections

·           Alerted driving situations in rural areas

·           High speed roads in urban areas comprising numerous intersections or interchanges where the majority of driver trips are of relatively short length.

·           Tunnels with operating speed ≥ 90 km/h.

 

The “alerted driving situations in rural areas” is deemed to be the applicable description in this case for the Weekes Bridge site. Further information can be found in Austroads Guide to Road Design Part 3: Geometric Design Clause 5.2.2.  (Comment from Engineering Designer: As a guide it could be noted that at 60km/h 0.5 seconds of travel accounts to approximately 8 metres.)

 

Vehicle Heights

 

There is a change in the height used for car tail lights. It has now been increased from 0.6m to 0.8 m. This would increase the sight distance in the Weekes Bridge scenario of a rear end crash at the Give Way sign.

 

Friction Factor

 

Longitudinal friction factors (ff) have also been revised in the 2010 Austroads guide. They are now referred to as ‘coefficient of deceleration’ (d).  The 2003 guide had a sliding scale related to vehicle speed from 50km/h to 130km/h (ff 0.52 to 0.35). The (ff) for 60 km/h was 0.48. In the revised 2010 edition there are now various values based on road conditions. The desirable 90th percentile coefficient of deceleration for general use is 0.36. For low volume roads the coefficient of 0.46 can be used. The use of this coefficient (0.46) in the sight distance calculations based on 60 km/h vehicle speed results in an increase in sight distance of less than 2 metres for cars which is equivalent to a 0.5 km/h difference in vehicle speed.

 

For speeds greater than 65 km/h the revised coefficient (0.46) results in shorter stopping sight distances and increased equivalent vehicle speeds for the available sight distance. The (ff) or (d) for trucks remains unchanged at 0.29. It should be noted that the available sight distance for trucks was generally greater than that for cars over crests, however, their braking characteristics resulted in significantly lower equivalent speeds.

 

The net effect of these changes to the method of calculating stopping sight distance is insignificant to the overall result. The case remains that with regard to Weekes Bridge sight distance is limited such that a single lane bridge can only be safely managed if the vehicle speed is reduced to 58 km/h for cars and 53 km/h for trucks approaching the crest east of the bridge.

 

Bridge Design

 

Reference is made to correspondence received from a resident pertaining to the bridge design, drawings and geotechnical investigation.

 

The height and location of Council’s existing rural bridges has historically been determined by what suited the road network rather than the stream flow.  Council’s engineering staff would concur with the fundamental comments that the engagement of a hydraulics engineer to model the flows of the stream as part of the designs for bridges would be beneficial. However, the reality for Council to model every stream over which Council has planned a replacement bridge is cost prohibitive due to the magnitude of Council’s infrastructure and competing needs across the community. Council do not have the funds to engage specialist consultants or construct consultants recommended designs.

 

Council has not commissioned a hydrological study of South Arm Creek at the Weekes Bridge site, however Council is conscious of its duty of care and the need to maintain stream flow capacity at road crossings to avoid scouring due to increased flow velocity. Advice from long standing employees of Council indicates that there is no evidence of this bridge been overtopped by flood waters.

 

On the eastern side of Weekes Bridge the original abutment remnants are still in place indicating that the bridge was originally approximately 30m long. Even though the bridge was lengthened when the abutment failed and emergency repairs where carried out, the fact that the old abutment structure was not removed has meant that the stream flow has always been restricted to the original channel width.

 

The proposed 34m bridge will locate the eastern abutment approximately 4m behind the old abutment structure which will be removed during construction. The proposed western abutment will be located as close as possible to the existing abutment but will be square to the deck rather than skewed as in the present bridge due to the nature of the prefabricated deck units. The net result is that although the bridge deck will be shorter than the existing deck, the channel width between the abutments will be wider than is currently available due to the constriction caused by the original failed abutment. This will most likely result in marginally reduced flood flow velocity and hence scouring, and lower upstream flood levels. These changes are illustrated on the attached diagram.

 

Council has sought an estimate of cost from consultants specialising in providing geotechnical and water way calculations. In essence if Council implemented these procedures, the additional cost to the bridge program would vary and are in the order of:

 

·           Hydrological assessment - $8,000 - $12,000

·           Geotechnical investigation – minimum 5 boreholes at $2,400 each – approx $12,000

·           Interpretive report - minimum $4,000.

 

This would result in a currently unrecognised additional cost to the timber bridge program in the order of $26,000 per bridge.

 

There were no boreholes drilled to investigate the depth and/or testing of soils prior to the Weekes Bridge repair or the proposed replacement this financial year. The lengthening of Weekes Bridge as per the current abutment location emanated from a decision by Council staff at the time repairs were undertaken to remedy the damage caused to the eastern abutment in order to maintain access beyond the bridge. The proposed abutment on the drawings aligns it back closer to the original site.

 

The general policy adopted by this Council since the bridge replacement program was implemented, has been to replace existing structures across waterways on the same alignment or as close as practical, and where funds permit, provide improvement to the waterway where feasible. In the case of Weekes Bridge the budget parameters reduced the existing structure width to that of a single lane bridge. Outside of the consideration of the width of the bridge, the Engineering Designer proposed the raising of the bridge deck by 350mm to allow an improved transition on to the bridge.

 

The drawings for timber bridges are, therefore in essence, ‘diagrammatical’ and for internal use only as much of the construction detail of pile placement, girder length and bracing is historically worked out on site by the bridge crew, taking into consideration the location of existing piles and abutments.

 

This Council has adopted the following parameters with respect to the bridge replacement program to maximize the allocation of available funding for the replacement of up to three bridges per year. The drawings have been prepared for internal use by the Nambucca Shire Council bridge gang who have wide experience in building timber bridge structures:

 

·           The basic timber bridge substructure design is based on ‘Specification for Construction of Timber Beam Bridges’ (DMR1976).

·           The exception being the introduction of prefabricated concrete deck units in accord with AS 5100 ‘Bridges’.

·           Piles are generally driven to refusal or to 4.5m as per ‘Specification for Construction of Timber Beam Bridges’.

 

The Weekes Bridge Community Committee requested Council consider building a two lane bridge the same width as the existing structure ‘like for like’. This option is not permissible as the existing bridge width does not comply with the current design standards for a two lane bridge and there would be a substantial cost in amending the prefabricated concrete deck units to provide a bridge outside the relevant standards.

 

The proposed replacement of a two lane bridge structure will be wider than the existing bridge to meet the minimum two lane bridge standard. Detailed below is a comparison of the deck width between the existing bridge and a proposed single to two lane bridge:

 

·           Existing bridge deck width is 6.6m between kerbs

·           Proposed single lane deck width is 4.4m between kerbs

·           Proposed two lane deck width is 7.2m between kerbs

 

Both the single lane and two lane bridge allows for a 600mm edge clearance either side of the travel lane in accordance with the bridge design standards.

 

Construction of a concrete bridge is presently outside the skill set of Council’s workforce.  If Council had elected to replace the timber structure with a concrete bridge, the project would be tendered externally as a Design and Construct Tender necessitating geotechnical investigation and provision for additional funding.

 

Matters raised in the public forum concerning the bridge construction

 

Comment     Bridge has been reduced in size by 8m

Response     The existing bridge is 38.7 m. The proposed single lane bridge is 34 m.

 

Comment:    Council creating black spot

Response:    Would concur with the statement that a single lane bridge will introduce new risks.  However this can be managed and drivers will be required to adjust their behaviour and adhere to standard signage used across the nation.

 

Comment:    Council has offered no other solutions than to add a few signs

Response:    Signs are the primary means used to alert drivers to unseen risks and are consistent with standard signage used across the nation.

 

Comment:    Sight distance is a problem

Response:    Would concur with the statement. This is a safety concern and can only be addressed by the use of signs to alert drivers of the unseen hazard over the crest.

 

Comment:    Narrowing of bridge will have effect on velocity of water and pressure on the bridge

Response:    A hydrological study of South Arm Creek at Weekes Bridge has not been undertaken by Council.  However the section of the bank where the bridge abutment is being relocated back near its original location is relatively high. The reduction of the cross sectional area of flow is not being significantly reduced.

 

Comment:    Unsuitable clay material will have to be removed before construction, suitable drains will be needed

Response:    An Erosion and Sediment Control Plan has been included in the project documentation as per the requirements of Council Fisheries permit.

 


Detailed Estimates

 

The reconstruction of Weekes Bridge on South Arm Road was identified in Council’s bridge replacement program for the 2011/12 financial year.  Provision of $325,000 was allocated in the 2011/12 budget to build a single lane bridge following Council’s adoption of the budget.  At the time of Council’s decision, staff were given no opportunity to undertake a formal design of the approaches and the decision to reduce the bridge to a single lane was based on financial circumstances and not on a technical basis.

 

To ensure ongoing sustainability of Council services it is essential to balance the community expectations with their willingness and capacity to pay for the infrastructure that underpins these services. With this principle in mind, works are often programmed to coincide with other projects in or around the vicinity.

 

Correspondence received from a resident made an assumption that guardrail was not included in the $325,000 and was an additional cost for the bridge. The resident estimated the guardrail at $32,280.00 (or $37,123 including a 15% contingency) based on rates used at Congarinni Bridge.  However, this work was provided by an external contractor who presumably would have included a profit margin.  Residents were advised at the site meeting that the guardrail was included in the $325,000 allocation for the bridge allocation.

 

The following is a detailed estimate for the construction of the bridge based on the cost of 2011/12 materials (timber and deck components). The construction of a single lane bridge including guardrail is $327,091.

 

Costing based on 2011/12 timber and deck prices

 

 

 

Single Lane

Two lane

Two Lane

 

 

34m, raise 0.35m

34m, raise 0.35m

40m, existing level

 

 

$

$

$

Bridge

 

      327,091.00

462,040.00

486,600.00

Approaches

       47,600.00

41,600.00

12,800.00

Sidetrack

 

       20,000.00

20,000.00

20,000.00

Signs and Linemarking

         5,080.00

2,680.00

2,680.00

Total $

 

      399,771.00

526,320.00

522,080.00

 

Notes:       

 

·           There is an additional two lane bridge option indicating a 40m length to best reflect ‘like for like’.  The additional 1.3m length over the existing bridge length is required to accommodate the prefabricated concrete deck units.

·           An allowance of $22,110 for supply and installation of guardrail to the bridge and 25m approaches is included in the 34m bridge options.

·           The side track cost remains consistent for a single or two lane bridge.

·           The cost for approaches varies according to the width of the bridge.

·           An allowance of $6000 is included to excavate 100 tonne of material from the north eastern road embankment to improve sight distance and length for the single lane option.

 

The full cost with the incorporation of signage, side track, and approach work for a single lane bridge is $399,771. In this case the construction of a side track was to be undertaken in conjunction with flood damage repairs to the west of the bridge and has now been included within the bridge project costs at $20,000 as the deferral of the bridge works will now most probably be outside the flood damage works.

 

Council have always used unit rates to estimate the bridges and these unit rates have merged very close to the estimated cost of the bridge with a marginal difference.

 


As reported there has been an increase in the new tender prices for the supply of materials (timber and deck components) and a revised estimate of costs for future construction is as follows:

 

 

 

Single Lane

Two lane

Two Lane

 

 

34m, raise 0.35m

34m, raise 0.35m

40m, existing level

 

 

 

 

 

Bridge

 

$352,548.00

$482,310.00

$514,547.00

Approaches

$47,600.00

$41,600.00

$12,800.00

Sidetrack

 

       $20,000.00

$20,000.00

$20,000.00

Signs & Linemarking

         $5,080.00

$ 2,680.00

$2,680.00

Total

 

$425,228.00

$546,590.00

$550,027.00

 

Notes:       

 

·           There is an additional two lane bridge option indicating a 40m length to best reflect ‘like for like’.  The additional 1.3m length over the existing bridge length is required to accommodate the prefabricated concrete deck units.

·           An allowance of $22,110 for supply and installation of guardrail to the bridge and 25m approaches is included in the 34m bridge options.

·           The side track cost remains consistent for a single or two lane bridge.

·           The cost for approaches varies according to the width of the bridge.

·           An allowance of $6000 is included to excavate 100 tonne of material from the north eastern road embankment to improve sight distance and length for the single lane option.

 

In conclusion, taking into account the financial, social and risk implications, it will be a decision for Council to consider and determine the level of service to be provided for this community, and the level of acceptable risk relating to a single or two lane bridge at the Weekes Bridge site.

 

 

CONSULTATION:

 

General Manager

Mayor and Councillors

Manager Assets

Engineering Designer

Manager Civil Works

Senior Overseer

Site Leader Bridges

 

 

SUSTAINABILITY ASSESSMENT:

 

 

 

Sustainability Assessment Factors

Option

Financial

Environmental

Social

Economic

Risk

Two Lane Bridge

û

ü

ü

Single Lane Bridge

ü

û

 

û   Not acceptable           ü   Acceptable                       C   an be managed   

 

Financial

 

Based on the number of ageing bridges requiring replacement across the Shire, the economic funding issues associated with rate pegging, working to a balanced budget and external state government funding factors such as the continued increase NSW RFS charges, Council began a review of the levels of service within the bridge program and where feasible considered the construction of single lane bridges.

 

There are no Federal or State Government grant programs for bridges on local roads.  The Local Infrastructure Renewal Scheme (LIRS) provides a 4% interest rate discount on approved capital works and Council is utilising the LIRS funding to replace the Eungai and Laverty's Bridges.

 

The recent quotations received for the supply of timber components for bridges (girders etc) have increased in price by approximately 18% on the contracts awarded for the supply in 2010.  These increases will have an effect on the construction cost for future budgets.

 

Environment

 

There are no significant environmental factors relating to a one lane or two lane bridge width, and certainly no major differentiation between the options on environmental grounds.

 

Social

 

It is clear that from a social perspective the option of a two lane bridge is the only acceptable option to the local community.  This view needs to be considered in light of the broader social landscape of the Shire as a whole.

 

Economic

 

There are no significant economic factors relating to either option and certainly no major differentiation between the options on economic grounds.

 

Risk

 

The risks associated in reducing the bridge width to single lane can not be eliminated but can be managed in accordance with Australian Standard 1742.2 (2009) Uniform Traffic Control devices and AustRoads Rural Road Design Guide (ARRDG). Council therefore must decide on what level of risk is acceptable compared to the cost and social implications of its decision.

 

With all Council’s activities there is an emphasis placed onto risk management and whether the risk can be mitigated or managed satisfactory. Compliance with the Australian Standards is seen as “best practice” in the industry for products and services in the Australian market, and is normally voluntary unless the products or services are regulated by the Government.

 

The reconstruction option of a two lane bridge provides the least risk to Council in terms of potential traffic issues.  The higher risks associated with a single lane bridge can be managed to a tolerable level, but not eliminated entirely, through control measures such as signage, line marking and reduced speed limits.

 

Council has about 35 bridges listed in Council’s Asset Management Plan that are classified in condition 4 (poor condition requiring close monitoring) and about 10 bridges classified in condition 5 (very poor - failure imminent). Weekes Bridge is one of 45 bridges listed in these condition ratings.

 

Council undertook minor maintenance on the bridge approximately 2 years ago with the knowledge that it was on the bridge replacement schedule for 2011/12.  Economically it is not a recommended viable or sustainable solution to expend any further funds on the bridge when it is to be replaced.  While the bridge is not in immediate danger of collapsing Council’s Site Leader - Bridges has undertaken a basic inspection of the bridge on 20 September 2012 and it is estimated that the replacement of the bridge could be potentially deferred for a period of 12 -24 months. Deferral will need consideration of a potential load and a speed limit on the bridge and a full detailed inspection to ensure that the replacement of the bridge can be deferred for a period greater than 12 months.

 


Summary

 

Overall the single lane option provides the best solution from a financial perspective and manages risk at a tolerable level.  The social discontent with this option is largely due to the increased risk associated with this option.  It is clear that the only acceptable option from a social perspective is the two lane option. However this social acceptance and related reduction in risk exposure comes at a cost.  This is Council’s dilemma balancing the conflicting factors, and ultimately that becomes a political decision.

 

 

FINANCIAL IMPLICATIONS:

 

Direct and indirect impact on current and future budgets

 

There will be no impact on the 2012/2013 budget as Council has resolved to reallocate funding to other projects.  Consideration of funds for either a single lane or two lane bridge will now be considered as part of future budgets.

 

Source of fund and any variance to working funds

 

The will be no variation to working funds in the current financial year.

 

 

 

Attachments:

1View

21690/2012 - Weekes Bridge Reconstruction

0 Pages

2View

24707/2012 - Weekes Bridge Reconstruction - September 2012

0 Pages

3View

32358/2012 - Report Attachment - Response to request for information on Weekes Bridge - December 2012

0 Pages

4View

32385/2012 - Report Attachment Weekes Bridge December 2012 - Abutment Diagram

0 Pages

  


Ordinary Council Meeting - 12 December 2012

Amended Report on Weekes Bridge Reconstruction - December 2012

 

Assistant General Manager Engineering Services Report

ITEM 11 .3   SF768              300812         Weekes Bridge Reconstruction

 

AUTHOR/ENQUIRIES:     Paul Gallagher, Assistant General Manager - Engineering Services         

 


 

Summary:

 

Following a delegation from Ms Joan Rossington on the Replacement of Weekes Bridge, South Arm at Council’s Ordinary meeting held 15 August 2012, Council resolved;

 

That the decision on Weekes Bridge be deferred to allow an onsite inspection and consultation with residents.  The inspection to occur at Council’s meeting on 30 August 2012.

 

An onsite inspection with residents is scheduled for Council at 11.30am on Thursday 30 August 2012.

 

 


 

Recommendation:

 

That Council receive and note the report on the Weekes Bridge re construction.

 

 


 

OPTIONS:

 

Under the provisions of Caretaker Mode any decision to vote additional funds towards the bridge would need to be deferred to the incoming Council which may necessitate another site inspection and report to Council on the matter.

 

1        Receive and note the report

2        Reconstruct the bridge as a single lane bridge using ’92 AUSTROADS BRIDGE Design Code

3        Vote an additional $150,000 to build a two lane bridge using Australian Standard AS 5100 (2004) Bridge Design Code

4        Defer the reconstruction of the bridge to the 2012/13 financial year and increase the vote and credit the works order (expenditure incurred to date) and place the bridge components into stock

5        Fund the additional $150,000 via

          a)       $150,000 from 2012/13 general funds (this will have a detrimental effect when it is coupled with the reduction of $191,545 within the FAGS grant (as reported to Council at the ordinary meeting held  26 July 2012)

          b)       $75,000 from 2012/13 general funds (effect similar to “a”) and $75,000 through bringing forward funding from the final year of the roads to recovery grant (R2R) which effectively will delete a rehabilitation project from the final year and will result in a shortened R2R program (moving the issue forward associated with decrease in funding)

6        Reallocate the funding of Weekes bridge to Laverty’s bridge to raise and lengthen the bridge to provide greater flood proofing (Consideration to load limiting the bridge maybe required)

7        Consider trialling the reduction in bridge deck to one lane through traffic barriers, sign posting and road markings and monitor the effect and install traffic counters to update the traffic counts

7        Bring another small bridge to the value of $325,000 forward within the program

8        Undertake extensive maintenance on the bridge and defer the replacement

 

DISCUSSION:

 

Ms Joan Rossington from South Arm Road addressed Council in the public forum on Wednesday 15 August 2012 with respect to the decision to replace Weekes Bridge with a single lane bridge and raised concern around the issue of sight distance onto the bridge as it is located after a blind bend.

 


Community consultation:

 

The first notification to Council in the consideration of reducing the bridge to one lane was provided at the meeting held on 12 May 2011 when Council considered the Draft 2011/12 Management Plan and Budget and the General Manager reported the following:

 

“To present a balanced budget, Council’s management is recommending the deletion or deferral of most new “bids” and some significant reductions and reallocations in existing programs.  It is an austerity budget……..The major changes which are recommended by Council’s management to the initial draft budget are as follows:

 

…..Item 6 The planned replacement of Weekes Bridge on South Arm with a single lane structure instead of a two lane structure (the existing bridge is 2 lane).  This is a reduction in service level and will provide a saving of $150,000”.

 

I advised Council at the meeting held on the 15 August, that I was relatively new to Council at the time of the budget preparation for 2011/12 and that there had been no community consultation leading up to the decision to replace the bridge with a single lane. The decision to reduce the bridge to a single lane emanated when the General Manager sought information from staff as to the cost of a single lane versus that of a two lane bridge to present a balance budget with other worthy competing projects

 

An issue identified with the lack of communication with respect to Weekes Bridge:

 

·            is the timing parameters for the preparation of the 2011/12 budget which did not facilitate any public consultation and the need to present a balanced budget to Council. This is being remedied with the development of the 10 year forward works program and every endeavour is now made to provide adequate consultation across the activities of Council.

·            The reduction in programs are highlighted in the General Managers report on the draft budget to Council which outlines all of the considerations for funding of projects either removed/added or amended from consideration, however the process of advertising the draft  budget may not highlight these changes nor may it reach the all of the public.

 

In the 2012/13 draft budget the General Manager report that the strategy from Council for tackling the financial issues are detailed on pages 12 and 13 of our Operational Plan and Delivery Program as follows:

 

"A balanced budget for 2012/2013 has only been achieved through the non-replacement of staff, additional borrowings and the deferral of required capital expenditure.  This is an unsustainable strategy.

 

The problem exists because Council's General Fund is being "squeezed" on the revenue side by rate pegging and on the cost side by depreciating infrastructure which has to be renewed and replaced in a timely way.  This infrastructure includes 170 bridges, 247km of sealed rural roads, 105km of urban streets and 345km of unsealed rural roads.  Inadequate funding of the depreciation of this infrastructure is the challenge for Council.  If the problem is left unattended, Council will fail in its core function of providing physical access to properties.

 

Cost shifting from the State Government such as through reduced regional road funding and increased contributions to the Rural Fire Service adds to the problem.  Council has to determine how it will reduce its services to a level which is financially sustainable.  In the latter part of 2012, Council will explore a number of measures that may help reduce its expenditure on infrastructure, including:

*  reduce the service level of bridges, with bridges going from two lane to single lane where possible

 

Bridge replacement program:

 

The reconstruction of Weekes Bridge on South Arm Road was identified in Council’s bridge replacement program for the 2011/12 financial year.  Provision of $325,000 was allocated in the 2011/12 budget to build a single lane bridge following Council’s adoption of the budget 

 

The bridge was scheduled for replacement before the end of the 2011/12 financial year through the months of May/June 2012 following the completion of Johns’s Bridge.  Due to the adverse weather experienced across the Shire, the entire bridge construction program was adversely affected and delayed the reconstruction of Weekes Bridge. All of the bridge components were ordered in the 2011/12 budget and stored at the Works Depot with the revote for 2012/13 encompassing labour and machinery only.

 

The weather forecast was favourable for work to commence on 27 August 2012 as a side track is required to be constructed to maintain access, however work has now been deferred pending the decision of Council following the site inspection. In the interim the bridge gang has been redeployed onto bridge maintenance.

 

Supply of bridge components:

 

Due to the production lead time required for the supply of bridge components, orders are now placed with suppliers some six months in advance of the budget and the items placed into store and booked out when works are scheduled to commence.

 

The bridge components for Weekes Bridge were ordered in the 2011/12 budget and stored at the Works Depot with the revote for 2012/13 encompassing labour and machinery only. In the event that the replacement of the bridge is deferred, the components would be credited back to the stores and most probably redirected to other works.

 

Condition of the bridge:

 

Council has about 35 bridges listed in Councils Asset Management Plan that are classified in condition 4 (poor condition requiring close monitoring) and about 10 bridges classified in condition 5 (very poor - failure imminent). Weekes Bridge is one of 45 bridges listed in these condition ratings

 

Council undertook minor maintenance on the bridge approximately 2 years ago with the knowledge that it was on the bridge replacement schedule for 2011/12. Economically it is not a recommended viable or sustainable solution to expend any further funds on the bridge when it is to be replaced.  Whilst the bridge is not in immediate danger of collapsing substantial work and/or a potential load limit on the bridge would need to be considered to ensure that the replacement of the bridge can be deferred.  .

 

Funding:

 

Councils Timber Bridge Replacement Infrastructure Planning Program identified the replacement cost of a two lane bridge for Weekes Bridge at $475,000 funded by external loans. The $150,000 has not been reallocated elsewhere across Council activities and there are also savings attributed on the interest that would have been payable on the loan.  The reduction in service level to that of a single lane bridge is a net reduction in Councils budget by $150,000  

 

There are no Federal or State Government grant programs for bridges on local roads.  The Local Infrastructure Renewal Scheme (LIRS) provides a 4% interest rate discount on approved capital works and Council is utilizing the LIRS funding to replace the Eungai and Laverty's Bridges.

 

If the replacement of the bridge is deferred and replaced with a two lane structure, the additional expenditure will result in something else being pushed back in the bridge replacement program and presumably increasing the risk of an unscheduled bridge failure. 

 

The decision to reduce the bridge to one lane is based on economical savings and presenting a balance budget with other competing programs, rate pegging and state government cost shifting. The replacement cost of a two lane bridge is $475,000 compared to that of a single lane bridge at $325,000. In considering the reduction in allocation, the issue of safety is addressed through the design parameters and appropriate road signage and markings in accordance with the Australian Standards. (Consideration is also being given in the design to battering the embankments on the eastern approach to assist with site distance)

 


Bridge design:

 

Based on the number of aging bridges requiring replacement across the Shire, the economic funding issues associated with rate pegging, working to a balanced budget and external state government funding factors such as the continued increase RFS charges, Council began a review of the levels of service within the bridge program and where feasible considered the construction of single lane bridges.

 

’92 AUSTROADS BRIDGE Design Code and the updated Australian Standard AS 5100 (2004) Bridge Design Code both state that the road bridge carriage way widths are determined by the Authority (Council) based on consistent levels of service along the section of roadway taking into account

a)       Road geometry

b)       Traffic volumes

c)       Bridge locality

The updated Australian Standard AS 5100 (2004) Bridge Design Code has been developed to facilitate design and build contracts and therefore does not comment on the economic considerations of the local Authority, whereas the ’92 AUSTROADS BRIDGE Design Code principles are based on projects administered by the infrastructure owners (Council)

 

With all Council’s activities there is an emphasis placed onto risk management and whether the risk can be mitigated or managed satisfactory. Compliance with the Australian Standards is seen as “best practice” in the industry for products and services in the Australian market, and is normally voluntary unless the products or services are regulated by the Government.

 

The risk when using the ’92 AUSTROADS BRIDGE Design Code  is addressed through the consideration of traffic counts, location of the site and the usage of signage and road markings for one lane bridges in accordance with Australian Standard 1742.2 (2009) Uniform Traffic Control devices.

 

Council use traffic counters to obtain the traffic volume flows across the local road network, these traffic counts are then used as a guide to determine the hierarchy of the road network, frequency of use and consideration of maintenance and construction treatments and designs of the pavement.

 

In determining the reduction to a single lane bridge the utilisation on the road is one of the factors considered, A projected flow of 180 vehicles per day has been assumed for design purposes due to the last traffic count being four years old  Traffic counts for South Arm Road were taken from Menzies Road towards the bridge (166 vehicles per day in 1997) and a count taken later between Williams Hill and Menzies Road (167 vehicles per day in 2008) which indicates little change in traffic movements..

 

At the Council meeting held on 15 August 2012, a traffic comparison was made between Weekes bridge and the newly constructed bridge at Deep Creek. I was advised by the General Manager that the traffic counts referenced for Deep Creek Bridge in discussion prior to the Council meeting were up to 1000 vehicles per day and this was relayed verbally at the meeting. The actual count has been verified and is 431 vehicles per day (over double that of Weekes Bridge) and are 8 years old (taken prior to the bridge being closed and possibly heavy influenced by traffic movements to the local quarry) Council has not taken any recent traffic counts on this road since the bridge was reopened to traffic

 

Council adhere to best practice guidelines when using either the ’92 AUSTROADS BRIDGE Design Code or Australian Standard AS 5100 (2004) Bridge Design Code Both codes in conjunction with Australian Standard 1742.2 (2009) Uniform Traffic Control devices allows the consideration in the reduction of service levels on a case by case basis following consideration of the road geometry, traffic volumes and the bridge locality (using this philosophy consideration of single or double lane bridge replacement within the Shire will be on a case by case basis)

 

 


CONSULTATION:

 

·           General Manager

·           Mayor

·           Manager Assets

 

 

SUSTAINABILITY ASSESSMENT:

 

Environment

 

There are no environmental implications associated with this report.

 

Social

 

There are social implications in the event the bridge is closed as it is to only access to this area.

 

Economic

 

The are economic implications associated with this report attributed to the perceived risk of accidents attributed to the narrowing of the bridge to one lane, The bridge construction and signage will be accordance with Australian Standards (and will consider the battering of the eastern approach batters).

 

Risk

 

The are risk implications associated with the narrowing of the bridge with respect to the sight distance onto the bridge, The vehicle counts for this area are projected at 180 vehicles a day with the majority of traffic movements being in the morning and evening (to and from work and school etc). The approach signage and road markings to denote a narrow bridge will be accordance with the Australian Standards.

 

 

FINANCIAL IMPLICATIONS:

 

Direct and indirect impact on current and future budgets

 

There will be a direct impact on the 2012/13 budget to construct a two lane bridge associated with the additional $150,000 required, and alternatively if the bridge program is amended to defer the reconstruction of Weekes Bridge.

 

Source of fund and any variance to working funds

 

The will a variation to working funds required for additional funding

 

 


Attachments:

1

 - CIRCULARISED DOCUMENT  - Plans - Bridge Design Details, Bridge Approaches Plan & Long Section, Signage, Linemarking & Guardrail

0 Pages

 


Ordinary Council Meeting - 12 December 2012

Amended Report on Weekes Bridge Reconstruction - December 2012

 

Assistant General Manager Engineering Services Report

ITEM 11.5    SF768              270912         Weekes Bridge Reconstruction - September 2012

 

AUTHOR/ENQUIRIES:     Paul Gallagher, Assistant General Manager - Engineering Services         

 


 

Summary:

 

An onsite inspection was conducted with the residents at 11.30 am on Thursday 30 August 2012 and Council resolved at the Ordinary meeting later that evening:

 

That a further report be provided to the new Council giving consideration to the issues raised at the site inspection conducted on 30 August 2012 and a source of funds be identified for the option of reinstating a two lane bridge.”

 

 


 

Recommendation:

 

That Council consider the following:

 

1        Constructing a single lane bridge as budgeted for in the 2012/13 Management Plan.

 

2        (a) Defer the reconstruction of Weekes bridge to the 2013/14 financial year, or beyond, depending on a further assessment of the existing bridge and increase the vote in future budget(s) depending on the time frame for deferral.

 

          (b) Credit the works order for Weekes bridge (expenditure incurred to date) and place the bridge components into stock for reuse on other bridges.

 

3        Bring forward one or more single lane bridges within the bridge replacement program currently classified condition 4 or 5 up to the value of $325,000.00 in which the components for Weekes Bridge can be used with the final decision on these bridges being based on the completion of the condition assessments.

 

 


OPTIONS:

 

1        Receive and note the report.

2        Reconstruct the bridge as a single lane bridge as budgeted for in the 2012/13 Management Plan.

3        Vote an additional $150,000 to build a two lane bridge.

4        Defer the reconstruction of the bridge to the 2013/14 financial year (or beyond) and increase the vote in future budget(s) depending on the time frame for deferral and credit the works order (expenditure incurred to date) and place the bridge components into stock.

5        Fund the additional $150,000 via:

a        $150,000 from 2012/13 general funds (this will have a detrimental effect when it is coupled with the reduction of $191,545 within the FAGS grant as reported to Council at the ordinary meeting held  26 July 2012).

b        $75,000 from 2012/13 general funds (effect similar to “a”) and $75,000 through bringing forward funding from the final year of the Roads To Recovery grant (R2R) which effectively will delete a road rehabilitation project from the final year and will result in a shortened R2R program (moving the issue forward associated with decrease in funding).

6        Reallocate the funding of Weekes bridge to Laverty’s bridge to raise and lengthen the bridge to provide greater flood proofing (consideration to load and speed limits on Weekes Bridge may be required).

7        Consider trialling the reduction in bridge deck width to one lane through traffic barriers, sign posting and road markings and monitor the effect.

8        Defer the replacement of Weekes Bridge and bring forward one or more bridge replacements currently classified condition 4 or 5 to the value of $325,000 within the bridge replacement program.

9        Undertake extensive maintenance on the bridge and defer the replacement of the bridge.

10      Eungai Bridge may potentially be constructed as a single lane bridge, there is a saving in expenditure as the budget has provision for the construction of a two lane bridge and this funding could be redirected to either Weekes or Laverty’s Bridge, as per option 6. This option is subject to consultation with the Eungai community or the savings be placed into a bridge reserve towards Weekes Bridge.

 

 

DISCUSSION:

 

Following a delegation from Ms Joan Rossington in the public forum with respect to the decision to replace Weekes Bridge with a single lane bridge and concern surrounding the issue of sight distance onto the bridge (as it is located after a blind bend), at Council’s Ordinary meeting held 15 August 2012, Council resolved:

 

          “That the decision on Weekes Bridge be deferred to allow an onsite inspection and consultation with residents.  The inspection to occur at Council’s meeting on 30 August 2012.”

 

The onsite inspection was conducted with the residents on Thursday 30 August 2012 at 11.30 am and Council resolved at the Ordinary meeting later that evening:

 

          That a further report be provided to the new Council giving consideration to the issues raised at an site inspection conducted on 30 August 2012 and a source of funds be identified for the option of reinstating a two lane bridge.”

 

A Community Consultation Committee has been formed and the correspondence from the committee is attached for Council’s information. The comments raised in their correspondence dated 12 September 2012 has been addressed through the course of this report with the exception of the request to be supplied detailed estimates for a single and two lane bridge. Council has structured the bridge gang for replacing timber bridge structures across the Shire and base the estimates for bridges on “unit rates” established over a period of time.

 

The Committee identified a few alternatives for consideration as follows:

 

1        Build a two lane bridge that is the same width

 

This option is not permissible as the existing bridge width does not comply with the current design standards for a two lane bridge and there would be a substantial cost in amending the prefabricated concrete deck units to provide a bridge outside the relevant standards.

 

The replacement of the new two lane bridge structure will be wider than the existing bridge to meet the minimum two lane bridge standard having a deck width of 7.2m between kerbs. As a comparison the proposed single lane bridge will have a deck width of 4.4m between kerbs (which allows 600 mm edge clearance each side of the travel lane in accordance with the design standards for a single lane bridge).

 

2        Repair the bridge to extend its life

 

Council undertook maintenance on the bridge approximately 2 years ago with the knowledge that it was on the bridge replacement schedule for 2011/12. There are five new girders in the bridge that were placed to facilitate heavy traffic access across the bridge for work on another bridge to the west of Weekes Bridge.

 

Whilst the bridge is not in immediate danger of collapsing (a heavy load or unplanned happening has the potential to cause damage or closure of the bridge), economically it is not a recommended viable or sustainable solution to expend any further funds on the bridge when it is to be replaced.  Council’s Bridge Foreman has undertaken a basic inspection of the bridge on 20 September 2012 and it is estimated that the replacement of the bridge could potentially be deferred for a period of 12 -24 months. Deferral will need consideration of a potential load and a speed limit on the bridge and a full detailed inspection to ensure that the replacement of the bridge can be deferred for a period greater than 12 months.

 

3        Wait for funding to become available

 

This report encompasses various options for consideration and funding options with the manipulation of the bridge replacement program.  One or more single lane bridge projects that are classified as condition 4 or 5 could be brought forward to the value of $325,000.00.

 

Community consultation Thursday 30 August 2012:

 

A summary of the concerns raised by the community on Thursday 30 August 2012 is as follows:

 

·           The lack of consultation from Council with the community on the bridge;

·           Safety implications associated with a one lane bridge and the sight distance;

·           The cost comparison of a two lane versus a single lane bridge;

·           What happened to the funding that was identified for a two lane bridge in a forward plan;

·           The relevant standards; and

·           The community are opposed to the bridge being replaced with a single lane bridge.

 

Consultation:

 

It was acknowledged that there had been no consultation with the community as presented within the report to Council on 15 August 2012 and this was reaffirmed at the meeting on site. The first notification to Council in the consideration of reducing the bridge to one lane was provided at the meeting held on 12 May 2011 when Council considered the Draft 2011/12 Management Plan and Budget and the General Manager reported the following:

 

“To present a balanced budget, Council’s management is recommending the deletion or deferral of most new “bids” and some significant reductions and reallocations in existing programs.  It is an austerity budget……..The major changes which are recommended by Council’s management to the initial draft budget are as follows:

 

…..Item 6 The planned replacement of Weekes Bridge on South Arm Road with a single lane structure instead of a two lane structure (the existing bridge is 2 lane).  This is a reduction in service level and will provide a saving of $150,000”.

 

I advised Council at the meeting held on the 15 August, that I was relatively new to Council at the time of the budget preparation for 2011/12 and that there had been no community consultation leading up to the decision to replace the bridge with a single lane. The decision to reduce the bridge to a single lane emanated when the General Manager sought information from staff as to the cost of a single lane versus that of a two lane bridge to present a balance budget with other worthy competing projects.

 

An issue identified with the lack of communication with respect to Weekes Bridge:

 

·          is the timing parameters for the preparation of the 2011/12 budget which did not facilitate any public consultation and the need to present a balanced budget to Council. This is being remedied with the development of the 10 year forward works program and every endeavour is now made to provide adequate consultation across the activities of Council.

·          The reduction in programs are highlighted in the General Managers report on the draft budget to Council which outlines all of the considerations for funding of projects either removed/added or amended from consideration, however the process of advertising the draft budget may not adequately highlight these changes nor reach the affected community area.

 

In the 2012/13 draft budget the General Manager reported that the strategy from Council for tackling the financial issues are detailed on pages 12 and 13 of our Operational Plan and Delivery Program as follows:

 

"A balanced budget for 2012/2013 has only been achieved through the non-replacement of staff, additional borrowings and the deferral of required capital expenditure.  This is an unsustainable strategy.

 

The problem exists because Council's General Fund is being "squeezed" on the revenue side by rate pegging and on the cost side by depreciating infrastructure which has to be renewed and replaced in a timely way.  This infrastructure includes 170 bridges, 247km of sealed rural roads, 105km of urban streets and 345km of unsealed rural roads.  Inadequate funding of the depreciation of this infrastructure is the challenge for Council.  If the problem is left unattended, Council will fail in its core function of providing physical access to properties.

 

Cost shifting from the State Government such as through reduced regional road funding and increased contributions to the Rural Fire Service adds to the problem.  Council has to determine how it will reduce its services to a level which is financially sustainable.  In the latter part of 2012, Council will explore a number of measures that may help reduce its expenditure on infrastructure, including:

 

*  reduce the service level of bridges, with bridges going from two lane to single lane where possible”

 

Risk (or safety) implications:

 

The risks associated in reducing the bridge width to single lane cannot be eliminated but can be managed in accordance with Australian Standard 1742.2 (2009) Uniform Traffic Control devices and AustRoads Rural Road Design Guide (ARRDG). Council therefore must decide on what level of risk is acceptable compared to the cost and social implications of its decision.

 

At the meeting on Thursday 30 August 2012 and in correspondence received by Council, the community raised their concerns that they believe that a single lane bridge will create a safety issue based on the inadequate sight distance to the approach of the bridge and the potential risk of a collision on the bridge.

 

It is recognised that there is an element of risk associated with the reduction of the bridge width to that of a single lane. When the decision was made to reduce the funding on the bridge and replace the existing two lane bridge with a single lane bridge, the Design Engineer referred to the various standards to ascertain whether the risk could be managed.

 

Following the onsite meeting on Thursday 30 August 2012 a numerical assessment was completed using the appropriate design standards (Australian Standard 1742.2 (2009) Uniform Traffic Control devices and AustRoads Rural Road Design Guide (ARRDG) and the attached engineers report reinforces the initial assessment that the risk can be managed, although not totally eliminated through the use of selected engineering techniques based on the traffic volumes, geometric road design, traffic speed and type of vehicles.

 

Road geometry:

 

South Arm Road is generally serpentine through undulating country, The posted speed limit is 100 km/h however the road has not been designed for this speed, with many low radius curves. Advisory speed signs have not been installed and drivers are required to drive to the conditions and determine the safe travel speed for themselves and this evidenced through the recent traffic counts with the 85th percentile speed being 74.5 km/h west of the bridge and 70.6 km/h east of the bridge.

 

The eastern approach has a 170 metre radius curve and a crest approx 70 metres from the bridge with a steep embankment above the eastern side of the road.  From the crest to the bridge the road has an 8% longitudinal fall on a bitumen surface at the approaches with the sealed surface approx 6m wide.

 

The western approach is across a flat flood plain with a 105 metre radius curve approx 100 metres from the bridge. To the west sight distance is approx 200 metres and can be improved by regular mowing of the western verge. To the east sight distance is restricted by the crest, the curve and the embankment.

 

The residents requested verification that the proposed engineering techniques for a one lane bridge adequately accounted for the sight distance issues on the eastern approach to the bridge  An analysis of stopping sight distances (SSD) and appropriate vehicle speeds for cars and trucks/buses on the eastern approach has been undertaken in accord with the recommendations of AustRoads Rural Road Design Guide (ARRDG).

 

Traffic volume:

 

Council use traffic counters to obtain the traffic volume flows across the local road network, these traffic counts are then used as a guide to determine the hierarchy of the road network, frequency of use and consideration of maintenance and construction treatments and designs of the pavement.

 

In determining the reduction to a single lane bridge the utilisation on the road is one of the factors considered, A projected flow of 180 vehicles per day was assumed for design purposes due to the last traffic count being four years old  Traffic counts for South Arm Road were taken from Menzies Road towards the bridge (166 vehicles per day in 1997) and a count taken later between Williams Hill and Menzies Road (167 vehicles per day in 2008) which indicates little change in traffic movements.

 

Council installed two traffic counters for a 14 day period from 5 September to 19 September to obtain updated values of vehicle usage on the road.

 

Located 200m west of the bridge 110 vehicles per day (AADT)

                                                         1.4% being heavy vehicle movement

                                                         85% speed 74.5 km/h

 

Located 300m east of the bridge 124 vehicles per day (AADT)

                                                         1.9 % being heavy vehicle movement

                                                         85% speed 70.6 km/h

Notation:

 

·           The counts are lower than the counts taken in 1997 and 2008.

·           The variance between the two recent counts (124 east  to 110 west) is based on property access between the two counters.

·           The highest travel periods are between the hours of 7.00 -11.00 am and 2.00 -5.00 pm.

·           It was observed from the readings that a vehicle had travelled the eastern section of road at 100 km/h.

 

The latest available traffic counts for this location indicate an Annual Average Daily Traffic (AADT) of 110 vehicle movements per day west of the bridge both directions and 124 vehicle movements per day east of the bridge both directions.  The Australian Standard for Traffic Control Devices (AS1742.2-2009) Clause 4.6.2.2(b) states that for bridges less than 60 metres long, GIVE WAY signs are not required for single lane bridges with an AADT less than 200.  The low AADT means that conflict with oncoming vehicles at the bridge would be rare and drivers would be required to concede right of way to vehicles already on the bridge.

 

Sight distance - is the length of roadway ahead that is visible to the driver. The available sight distance on a roadway should be sufficiently long to enable a vehicle travelling at or a near the design speed to stop before reaching a stationary object in its path. Although greater lengths of visible roadway are desirable, the sight distance at every point along a roadway should be at least that needed for a below-average driver or vehicle to stop.

 

Decision sight distance - is the distance required for a driver to detect an unexpected or otherwise difficult-to-perceive information source, recognise the source, select an appropriate speed and path, and initiate and complete the required manoeuvre safely and efficiently. Because decision sight distance gives drivers additional margin for error and affords them sufficient length to manoeuvre their vehicles at the same or reduced speed rather than to just stop, its values are substantially greater than stopping sight distance.

 

Four options have been assessed for a single lane bridge, identifying risks and possible mitigation measures within the attached report:

 

1        Single lane bridge with no Give Way sign

2        Single lane bridge with Give Way sign on the eastern approach

3        Single lane bridge with Give Way sign on the western approach

4        Single lane bridge with Give Way sign on the both approaches

 

The potential risk of an accident on Weekes Bridge:

 

The risks associated in reducing the bridge width to single lane cannot be eliminated but can be managed in accordance with Australian Standard 1742.2 (2009) Uniform Traffic Control devices and AustRoads Rural Road Design Guide (ARRDG).

 

A single lane bridge creates an element of risk of a head on collision of vehicles on the bridge. The SSD have been calculated for west bound vehicles sighting a east bound vehicle as it arrives at the western end of the bridge. The distance has been calculated for the west bound vehicle to stop 25 metres before the eastern end of the bridge. The stopping sight distance for cars is 77 metres and for trucks 82 metres. By reshaping of the embankment within the road reserve the truck SSD could be increased to 105 metres. These distances equate to a travel speed of 68 km/h for cars and 62 km/h for trucks. The 170 metre radius curve has approx 3% cross fall and according to ARRDG the safe travel speed is approx 70 km/h.

 

If a west bound vehicle was stopped to give way to an oncoming vehicle the risk exists of another west bound vehicle being responsible for a rear end collision. Given the most recent AADT and past AADT this situation of 3 vehicles arriving at the bridge at the same time would be rare. The worst scenario (and one that has been expressed by the residents) would be for the school bus to be stopped and a truck to come from behind or vice versa.

 

The SSD has been calculated for vehicles stopping at the back of a 12 metre bus or truck, stopped 25 metres before the bridge. With reshaping of the bank the SSD for cars would be 65 metres and trucks or buses 82 metres. The equivalent safe travel speeds would be 58 km/h for cars and 53 km/h for trucks. It should be noted that these distances are calculated to the tail lights (600mm above the road surface) to allow for night traffic movements. The school bus however travels normally during daylight hours and the back of a bus or truck is visible more than 2.5 metres above the road. This increases the actual sight distance to the back of a bus or truck during daylight hours.

 

Risk Mitigation Measures:

 

The following measures will not eliminate the risk but manage the risk based on the vehicle movements:

 

·      Line marking and signage as recommended by AS1742.2-2009 Clause 4.6.2.2(a)(i) & (ii).

·      Reduce the speed limit for 500 metres before and after the bridge to 60 km/h.

·      Install REDUCE SPEED ONE LANE BRIDGE AHEAD signs on both approaches.

·      To reinforce the speed reduction, ripple bars could be installed on the road surface before the curve on the eastern approach.  This will increase Council’s inspection and maintenance responsibilities in this area to ensure ongoing risk mitigation.

·      Resurfacing of the road would ensure the friction factors are at or above those assumed in the ARRDG stopping distance calculations. (NOTE – it was intended to complete a reseal of the pavement once the bridge and abutments were completed, this is separate funding under the reseal program).

 

Bridge replacement program:

 

The reconstruction of Weekes Bridge on South Arm Road was identified in Council’s bridge replacement program for the 2011/12 financial year.  Provision of $325,000 was allocated in the 2011/12 budget to build a single lane bridge following Council’s adoption of the budget.

 

The bridge was scheduled for replacement before the end of the 2011/12 financial year through the months of May/June 2012 following the completion of Johns’s Bridge.  Due to the adverse weather experienced across the Shire, the entire bridge construction program was adversely affected and delayed the reconstruction of Weekes Bridge. All of the bridge components were ordered in the 2011/12 budget and stored at the Works Depot with the revote for 2012/13 encompassing labour and machinery only.

 

Work was scheduled to commence on 27 August 2012 with a favourable weather forecast, however work has been placed on hold pending Council’s decision. As an interim measure the bridge gang has been redeployed onto bridge maintenance work, however a decision is now required otherwise the bridge program for 2012/13 is in jeopardy of not being completed.

 

For Council to maintain a balanced budget for the 2012/13 and not draw on general funds at the detriment of other infrastructure projects the only option for funding the two lane bridge is to amend the bridge replacement program by:

 

·           Defer the reconstruction of Weekes bridge to the 2013/14 financial year or beyond and increase the vote in future budget(s) depending on the time frame for deferral.

·           Credit the works order (expenditure incurred to date) and place the bridge components into stock.

·           Bring forward one or more single lane bridges within the bridge replacement program currently classified as condition 4 or 5 up to the value of $325,000.00 in which the components for Weekes Bridge can be used. Candidate bridges may consist of Millers Bridge (currently has a 10T load limit impeding access for residents), Swans, Garrett’s and Top Bridges which are all on the program for the next three financial years. Final decision will be based on the completion of condition assessments currently in progress.

·           In the event that Eungai Bridge is constructed as a single lane bridge, the anticipated saving in expenditure could be placed into a reserve towards the construction of Weekes Bridge.  (NOTE: This option is subject to consultation with the Eungai community and may receive the same reaction from the community as Weekes Bridge)

 

 

CONSULTATION:

 

General Manager

Mayor and Councillors

Manager Civil Works

Manager Assets

Engineering Designer

 

SUSTAINABILITY ASSESSMENT:

 

 

 

Sustainability Assessment Factors

Option

Financial

Environmental

Social

Economic

Risk

Two Lane Bridge

û

[

ü

[

ü

Single Lane Bridge

ü

[

û

[

[

 

û   Not acceptable                    ü   Acceptable               [   Can be managed     

 

Financial:

 

Based on the number of ageing bridges requiring replacement across the Shire, the economic funding issues associated with rate pegging, working to a balanced budget and external state government funding factors such as the continued increase NSW Rural Fire Service charges, Council began a review of the levels of service within the bridge program and where feasible considered the construction of single lane bridges.

 

Financially the single lane option is preferable to Council given the current budget position, reduction in FAG funding and the desired position of establishing a balanced budget, and funding the additional $150,000 is at the detriment of the current and or future infrastructure programs.

 

The decision to reduce the bridge to one lane is based on economical savings and presenting a balanced budget with other competing programs, rate pegging and State Government cost shifting. The replacement cost of a two lane bridge is $475,000 compared to that of a single lane bridge at $325,000. In considering the reduction in allocation, the issue of safety is addressed through the design parameters and appropriate road signage and markings in accordance with the Australian Standards.

 

Council’s Timber Bridge Replacement Infrastructure Planning Program identified the replacement cost of a two lane bridge for Weekes Bridge at $475,000 funded by external loans. The $150,000 has not been reallocated elsewhere across Council activities and there are also savings attributed on the interest that would have been payable on the loan.  The reduction in service level to that of a single lane bridge is a net reduction in Councils’ budget by $150,000.

 

There are no Federal or State Government grant programs for bridges on local roads.  The Local Infrastructure Renewal Scheme (LIRS) provides a 4% interest rate discount on approved capital works and Council is utilising the LIRS funding to replace Eungai and Laverty's Bridges.

 

If the replacement of the bridge is deferred and replaced with a two lane structure, the additional expenditure will result in something else being pushed back in the bridge replacement program and presumably increasing the risk of an unscheduled bridge failure. 

 

Council’s resolution sought the identification and source of funds for the option of reinstating a two lane bridge for Council to maintain a balanced budget for the 2012/13 the options open for consideration are:

 

·            Vote an additional $150,000 to build a two lane bridge via

a        $150,000 from 2012/13 general funds (this will have a detrimental effect when it is coupled with the reduction of $191,545 within the FAGS grant (as reported to Council at the ordinary meeting held  26 July 2012).

b        $75,000 from 2012/13 general funds (effect similar to “a”) and $75,000 through bringing forward funding from the final year of the roads to recovery grant (R2R) which effectively will delete a road rehabilitation project from the final year and will result in a shortened R2R program (moving the issue forward associated with decrease in funding).

·           Defer the reconstruction of the bridge to the 2013/14 financial year (or beyond) and increase the vote in future budget (s) depending on the time frame for deferral and credit the works order (expenditure incurred to date) and place the bridge components into stock and bring forward one or more bridge replacements with the condition 4 or 5 assessment within the bridge replacement program to the value of $325,000.

·           Eungai Bridge may potentially be constructed as a single lane bridge, there is an anticipated saving in expenditure as the budget has provision for the construction of a  two lane bridge and this funding could be redirected to either Weekes or Laverty’s Bridge. This option is subject to consultation with the Eungai community

 

The recent quotations received for the supply of timber components for bridges (girders etc) have increased in price by approximately 18% on the contracts awarded for the supply in 2010.  These increases will have an effect on the construction costs for future budgets including Weekes if the bridge is deferred.

 

Environmental

There are no significant environmental factors relating to either option, and certainly no major differentiation between the options on environmental grounds.

 

Social

It is clear that from a social perspective the option of a two lane bridge is the only acceptable option to the local community.  This view needs to be considered in light of the broader social landscape of the Shire as a whole.

 

Economic

There are no significant economic factors relating to either option, and certainly no major differentiation between the options on economic grounds.

 

Risk

The risks associated in reducing the bridge width to single lane can not be eliminated but can be managed in accordance with Australian Standard 1742.2 (2009) Uniform Traffic Control devices and AustRoads Rural Road Design Guide (ARRDG). Council therefore must decide on what level of risk is acceptable compared to the cost and social implications of its decision.

 

With all Council’s activities there is an emphasis placed onto risk management and whether the risk can be mitigated or managed satisfactory. Compliance with the Australian Standards is seen as “best practice” in the industry for products and services in the Australian market, and is normally voluntary unless the products or services are regulated by the Government.

 

The reconstruction option of a two lane bridge provides the least risk to Council in terms of potential traffic issues.  The higher risks associated with a single lane bridge can be managed to an tolerable level, but not eliminated entirely, through control measures such as signage, line marking and reduced speed limits.

 

Council has about 35 bridges listed in Council’s Asset Management Plan that are classified in condition 4 (poor condition requiring close monitoring) and about 10 bridges classified in condition 5 (very poor - failure imminent). Weekes Bridge is one of 45 bridges listed in these condition ratings.

 

Council undertook maintenance on the bridge approximately 2 years ago in order to facilitate the replacement of a flood damaged bridge located further along South Arm Road and with the knowledge that it was on the bridge replacement schedule for 2011/12.  Economically it is not a recommended viable or sustainable solution to expend any further funds on the bridge when it is to be replaced.  Whilst the bridge is not in immediate danger of collapsing Council’s Bridge Foreman has undertaken a basic inspection of the bridge on 20 September 2012 and it is estimated that the replacement of the bridge could be potentially deferred for a period of 12 -24 months.  Deferral will need consideration of a potential load and speed limit on the bridge and a full detailed inspection to ensure that the replacement of the bridge can be deferred for a period greater than 12 months.

 

Summary

Overall, the single lane option provides the best solution from a financial perspective to Council and manages risk at a tolerable level.  The social discontent with this option is largely due to the increased risk associated with this option.  It is clear that the only acceptable option from a social perspective is the two lane option, however this social acceptance (and related reduction in risk exposure) comes at a cost.  This is Council’s dilemma balancing the conflicting factors, and ultimately that becomes a political decision.

 

 

FINANCIAL IMPLICATIONS:

 

Direct and indirect impact on current and future budgets

 

There will be a direct impact on the 2012/13 budget to construct a two lane bridge associated with the additional $150,000 required, and alternatively if the bridge program is amended to defer the reconstruction of Weekes Bridge.

 

An amendment can be made to the bridge program by deferring the construction of Weekes Bridge by bringing forward other projects to the value of $325,000.00 which will have a NIL impact on the current 2012/13 financial budget.  However this could potentially impact the 2013/14 budget or beyond.

 

 

Source of fund and any variance to working funds

 

There will be a variation to working funds attributed to either a positive or marginally negative impact depending on the bridges chosen in lieu of Weekes Bridge.

 

 


Attachments:

1

21690/2012 - Weekes Bridge Reconstruction Council Report 30 August 2012

0 Pages

2

23895/2012 - Weekes Bridge Replacement - Advice that Community Consultation Committee has been formed and issues arising from meeting with Council

0 Pages

3

 - CIRCULARISED DOCUMENTS
Email from Chezmar Bus Service (Trim BR-BV-2: 22406/2012)

0 Pages

4

 - CIRCULARISED DOCUMENT
Plans - Bridge Design Details, Bridge Approaches Plan & Long Section, Signage, Linemarking & Guardrail provided for new Councillors only. Were previously supplied to all Councillors with the 30 August 2012 report.

0 Pages

5

 - CIRCULARISED DOCUMENTS Item 11.5
Engineering Designers Report on Weekes Bridge
(Trim BR-BV-2: 24709/2012)

0 Pages

 


Ordinary Council Meeting - 12 December 2012

Amended Report on Weekes Bridge Reconstruction - December 2012

 

RESPONSE TO REQUEST FOR INFORMATION ON WEEKES BRIDGE – DECEMBER 2012

 

 

The General Manager received a request to provide an explanation to a number of issues raised by a community member in relation to Weekes Bridge.  The General Manager advised that the matter would be addressed by the Assistant General Manager Engineering Services and included in a report to Council on the 12 December 2012.

 

1        SAFETY – BUDGET

 

In the Laverty’s Bridge report the option which requires additional expenditure was recommended in order to improve safety. At the same time, it was recommended in the Weekes Bridge report to compromise safety to meet budget constraints.

 

Q 1:      Under what circumstances will a council report recommend to consider budget over safety and what are the cases were safety concerns will overrule budget considerations?”

 

R 1:      With all Council’s activities there is an emphasis placed on risk management of some kind and whether the risk can be mitigated or managed satisfactory. These are conscious decisions made by staff when developing budgets or in fact making any day to day decision. Therefore safety concerns will not necessarily overrule budget considerations. To this effect, each council report contains a “sustainability assessment” which outlines the implications of risk and budget for Council.

 

            In the most recent report to Council, the risks associated in reducing the bridge width to single lane have been investigated and it was reported “can not be eliminated but can be managed” in accordance with Australian Standard 1742.2 (2009) Uniform Traffic Control devices and AustRoads Rural Road Design Guide (ARRDG). Council therefore must decide on what level of risk is acceptable compared to the cost and social implications of its decision.

 

            The decision to reduce Weekes bridge to a single lane emanated from a financial basis to present a balanced budget to Council as the General Fund is being "squeezed" on the revenue side by rate pegging and on the cost side by depreciating infrastructure which has to be renewed and replaced in a timely way.

 

            The consideration of reducing the bridge to one lane was provided to Council at the meeting held on 12 May 2011 when Council considered the Draft 2011/12 Management Plan and Budget and the General Manager reported the following: “To present a balanced budget, Council’s management is recommending the deletion or deferral of most new “bids” and some significant reductions and reallocations in existing programs.  It is an austerity budget……..The major changes which are recommended by Council’s management to the initial draft budget are as follows:

            …..Item 6 The planned replacement of Weekes Bridge on South Arm with a single lane structure instead of a two lane structure (the existing bridge is 2 lane).  This is a reduction in service level and will provide a saving of $150,000”. The estimated cost for the budget on Weekes Bridge was then reduced by a net value of $150,000.

 

 

2        PROJECT COSTINGS PRESENTATION

 

The presentation format of project costings in the two above-mentioned council reports is significantly different. While in the presentation for Laverty’s Bridge the costings present and sum a wide scope of associated costs into a grand total; for Weekes Bridge only the bridge work cost is shown. Consequently, in the Weekes Bridge report the grand total remains unknown and the true budget impact of the project can’t be assessed.

 

Q 2:      Does the council have any guidelines for costings presentation? In what cases will a report to council include the overall expenses of a project and when will it be just one costings item?”

 

R 2:      An overall draft budget encompassing all of Council’s activities is provided to Council for consideration in April/May of each year. This lists individual projects such as land slips, bridges etc.  However, reseals and heavy patching are not individually itemised as they are considered one project even though they may encompass a number of locations.

 

            Council capital works are reported individually on a quarterly basis to council and this report provides a progress status and foreshadows whether the expenditure is on, under or over budget with and explanation of works in excess of the budget allocation. Once a budget is approved by Council, under the Local Government Act the actual implementation of works becomes an operational matter.

 

            As a general rule the overall cost of a project would normally be provided in a report to Council for a specific project unless individual factors required a more detailed cost breakup. In the case of Laverty’s Bridge the design options provided a significant realignment of the road therefore more detail was provided to allow assessment of the options. A more detailed estimate has since been provided for Weekes Bridge.

 

          The QBR process provides Council with the final cost of the projects upon their completion.

 

 

3        “ENVIRONMENT – BUDGET

 

The Laverty’s Bridge report recommends raising the bridge deck to allow extra flow and reduce the risk of flooding at non-budgeted cost.  In the Weekes Bridge case, this design is compromising stream flow and increase the likelihood and frequency of flooding for the sake of budget saving.

 

Q 3:      Under what circumstances will stream flow considerations justify extra budget expenditure and when is stream flow is less important than budget cuts?”

 

R 3:      The conjecture of stream flow on Weekes bridge is subjective which would require hydraulic modelling and flood studies and in Weekes Bridge the current abutment was relocated after a slippage. This was verified by Council staff who worked on the repairs at the time.

 

            The main differing factor between Weekes Bridge and Laverty’s Bridge is that an amount which has been allocated for the projects. The former Director Engineering Services made provision for flood proofing the bridge at Laverty’s in the draft forward plans. The increase in deck height would greatly reduce, but not totally eliminate, the effects of flooding at this site.  Without full hydraulic modelling and flood studies it is difficult to quantify these benefits, however anecdotal evidence suggests the increase of 1.75 metres would reduce the likelihood of the bridge being cut during flooding and would greatly reduce the time the bridge is inundated by floodwater.

 

            Closure of Laverty’s Bridge due to flooding has serious economic consequences to a significant area of the Shire including The Pub With No Beer which is an iconic tourist attraction. Access to areas west of this bridge can be disrupted for many days having a major impact not only on the economy but also on emergency services and food supplies. The loss of income is validated by the recent closure of Boat Harbour Road due to a landslip which placed a major burden on the community due to reduced tourist activity. It is considered unlikely that a similar disruption would occur at Weekes Bridge.

 

 

4        “LIKE- FOR-LIKE” POLICY

 

When you examine the council approach to these two cases it is noticeable that in both a 'like-for-like' policy was not followed.

 

Q 4:      Under what circumstances will the council recommend  an exception to the like-for-like policy? When will it be less for like and when will it be more for like?”

 

R 4:      Council has about 35 bridges listed in Council’s Asset Management Plan that are classified in condition 4 (poor condition requiring close monitoring) and about 10 bridges classified in condition 5 (very poor - failure imminent). Weekes Bridge is one of 45 bridges listed in these condition ratings

 

            Historically, Council has reconstructed bridges “like for like” at a similar standard to the one being replaced with consideration to improving the standard where possible. Due to the changed economic climate conditions faced by Council, a decision was made to reduce the standard and level of service of this bridge to save a net value of $150,000. It is acknowledged in normal circumstance the reduction of levels of service would be justified by detailed analysis and community consultation. Therefore the decision to reduce the bridge to a single lane was based on financial circumstances surrounding Council and not that of a technical basis.

 

            It has always been the intention to reduce the flooding and improve the Laverty’s Bridge and the provision was made within the budget based on the number of flooding events and repairs to the road. The revised configuration of Taylors Arm and North Bank Roads provides an advantage in that the existing section of road to the west of the bridge is subject to substantial damage by floodwater and the revised road arrangement will lessen the effects of floodwater on the road. 

 

 

5        “BUDGET SUSTAINABILITY

 

The council has repeatedly expressed the need to cut budget spending in order to have a sustainable budget. As was presented to IPART and the residents, the Council pledged to reduce spending by cutting service levels; especially bridge construction. It seems that in the case of Laverty’s Bridge all this was put aside and the report is recommending extra spending of $160K.

 

Q 5:      If there are cases when non-budgeted spending is approved, why does Weekes Bridge not qualify to be one of these cases?”

 

R 5:      The 2012/13 budget has an allowance of $525,000 for reconstruction of Laverty’s Bridge and $845,000 for rehabilitation/reconstruction of Taylors Arm Road.

 

Council have provided a budget allowance for the improvement of Taylors Arm Road encompassing bulk stabilisation, heavy patching, resealing and roadworks associated with the replacement of Laverty’s Bridge.  Work to date on Taylors Arm Road has focused on heavy patching and resealing, rather than the more traditional bulk stabilisation.  This targeted work results in a more cost effective treatment and therefore allows an improvement to the physical assets within the existing budget as allocated.

 

Q 6:      If Council can save $160K on the road improvement plan, why will it not be allocated to build two lanes in Weekes Bridge?”

 

R 6       The 2012/13 budget has provision for various work activities encompassing direct budgets related to such things as landslips, bridge replacement and road works. Any additional funding beyond the $325,000 for Weekes Bridge is at the expense of another project or Council’s general fund.

 

These individual programs are not cross subsidised, in that any under expenditure within that work program area is either redirected back into general fund at the end of the year or back into another similar work activity (ie road expenditure is maintained on road works, bridge works are maintained on bridges etc).

 


Ordinary Council Meeting - 12 December 2012

Amended Report on Weekes Bridge Reconstruction - December 2012