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ŌTAKI TO NORTH OF LEVIN PFRSs
Report No. 1: Forest Lakes Project Feasibility Report
Prepared for NZ Transport Agency
April 2013
Report 1: Forest Lakes
Status: Final April 2013 Project number: Z1925700 Our ref: PFR01 Forest Lakes Final v2.docx
This document has been prepared for the benefit of NZ Transport Agency. No liability is accepted by this company or any employee or sub-consultant of this company with respect to its use by any other person.
This disclaimer shall apply notwithstanding that the report may be made available to other persons for an application for permission or approval to fulfil a legal requirement.
QUALITY STATEMENT
PROJECT MANAGER PROJECT TECHNICAL LEAD
Tracy Couchman Phil Peet
PREPARED BY
………………………………............... ……/……/…… Ian Robertson
CHECKED BY
………………………………............... ……/……/…… Phil Peet
REVIEWED BY
………………………………............... ……/……/…… Marten Oppenhuis
APPROVED FOR ISSUE BY
………………………………............... ……/……/…… Phil Peet
WELLINGTON Level 1, 123 Taranaki Street, Wellington 6011 PO Box 9624, Te Aro, Wellington 6141 TEL +64 4 381 6700, FAX +64 4 381 6739
REVISION SCHEDULE
Rev No
Date Description Signature or Typed Name (documentation on file).
Prepared by Checked by Reviewed by Approved by
A 09/10/12 Draft for Client Review DR PP MO PP
B 21/11/12 Draft for KCDC Review DR PP MO PP
C 22/2/12 Final IR PP MO PP
Report 1: Forest Lakes
Status Final April 2013 Project number: Z1925700 i Our ref: PFR01 Forest Lakes Final v2.docx
Report 1: Forest Lakes
Status Final April 2013 Project number: Z1925700 ii Our ref: PFR01 Forest Lakes Final v2.docx
Executive Summary This Project Feasibility Report (PFR) is one of a number of reports being undertaken to determine the package of improvements that should be implemented to improve the safety and efficiency of the highway between Ōtaki and north of Levin as part of the Wellington Northern Corridor Road of National Significance (RoNS).
The purpose of this report is to determine the feasibility of undertaking safety improvements along the section of SH1 from immediately north of Taylors Road to the Pukehou Railway Overbridge.
In order to reduce the number of serious crashes which primarily involve vehicles crossing the centreline, the installation of a wire rope median barrier along with carriageway widening and curve realignment was investigated.
A summary of the economic analysis is shown below.
Table 1-1: Option Summary
Option Description Capital Costs NPV Benefits Benefit Cost Ratio
Option 1-1: Desirable RoNS
Standards
$14.0M $17.4M 1.2
Option 1-2: Compromised RoNS
Standards
$11.4M $16.8M 1.4
It is recommended that Option 1-2 be the preferred option at this location due to the significant safety benefits. However, this option needs to be considered in light of the short medium and long term strategy for this section of highway which is being developed concurrently with this PFR.
Report 1: Forest Lakes
Status Final April 2013 Project number: Z1925700 i Our ref: PFR01 Forest Lakes Final v2.docx
Report 1: Forest Lakes
Status: Final April 2013 Project number: Z1925700 Our ref: PFR01 Forest Lakes Final v2.docx
NZ Transport Agency
Report 1: Forest Lakes
CONTENTS
Executive Summary .................................................................................................................................. ii
1 Introduction and Background .............................................................................................................. 1
2 Projects Currently Being Investigated ................................................................................................ 1
3 Description of Problem ....................................................................................................................... 3
3.1 Ōtaki to North of Levin ................................................................................................................... 3
3.2 Forest Lakes .................................................................................................................................. 3
4 Site Description .................................................................................................................................. 3
5 Traffic Statistics .................................................................................................................................. 5
6 Crash History ...................................................................................................................................... 6
6.1 Crash Data..................................................................................................................................... 6
6.2 Crash Risk ..................................................................................................................................... 8
7 Alternatives and Options Considered ................................................................................................. 8
7.1 Option 1-1: Desirable RoNS Standard ........................................................................................... 9
7.2 Option 1-2: Absolute Minimum RoNS Standard ............................................................................ 9
7.3 Other Aspects .............................................................................................................................. 10
8 Design Statement ............................................................................................................................. 11
9 Cost Estimates ................................................................................................................................. 11
10 Economic Assessment and Risk Assessment .................................................................................. 12
10.1 Basis of Economic Analysis ......................................................................................................... 12
10.2 Travel Time Savings .................................................................................................................... 13
10.3 Vehicle Operating Cost Savings .................................................................................................. 13
10.4 Crash Benefits ............................................................................................................................. 14
10.5 Maintenance Costs ...................................................................................................................... 14
10.6 Benefit Cost Ratio Results ........................................................................................................... 14
10.7 Risk Assessment ......................................................................................................................... 15
11 Assessment Profile ........................................................................................................................... 15
11.1 Strategic Fit ................................................................................................................................. 15
11.2 Effectiveness ............................................................................................................................... 15
11.3 Efficiency ..................................................................................................................................... 16
12 Social and Environmental Assessment ............................................................................................ 16
13 Geotechnical Requirements ............................................................................................................. 17
14 Land Requirements .......................................................................................................................... 17
15 Resource Management Issues ......................................................................................................... 17
15.1 District Plan Provisions ................................................................................................................ 17
Report 1: Forest Lakes
Status: Final April 2013 Project number: Z1925700 Our ref: PFR01 Forest Lakes Final v2.docx
15.2 Regional Plans............................................................................................................................. 18
16 Maintenance Issues .......................................................................................................................... 18
17 Conclusions and Recommendations ................................................................................................ 18
LIST OF TABLES
Table 1-1: Option Summary ..................................................................................................................... ii
Table 5-1: Saturn Base 2011/2041 Network Modelling Results ............................................................... 5
Table 6-1: Annual Distribution of Crashes ............................................................................................... 6
Table 6-2: CAS Crash Type ..................................................................................................................... 6
Table 6-3: HRRRG Crash Type ............................................................................................................... 7
Table 6-4: Crash Causation Factors of Reported Injury Crashes ............................................................ 7
Table 6-5: Environmental Factors ............................................................................................................ 7
Table 9-1 : Cost Estimate ........................................................................................................................ 11
Table 10-1: Crash Benefits .................................................................................................................... 14
Table 10-2: Economic Analysis Summary ............................................................................................. 14
LIST OF FIGURES
Figure 2-1: Projects Currently Being Investigated ..................................................................................... 2
Figure 4-1: Study Area Location Map ........................................................................................................ 4
Figure 7-1: Option 1 Typical Section – Desirable RoNS Standard ............................................................ 9
Figure 7-2: Option 2 Typical Section – Compromised RoNS Standards .................................................. 10
Figure 17-1: Pukehou “Hill of Dedication” .................................................................................................. 2
APPENDICES
Appendix A Photographs
Appendix B Traffic Data
Appendix C Crash Data
Appendix D Outline Plans
Appendix E Cost Estimates
Appendix F Economic Analysis Worksheets
Report 1: Forest Lakes Introduction and Background
Status: Final April 2013 Project number: Z1925700 Page 1 Our ref: PFR01 Forest Lakes Final v2.docx
1 Introduction and Background Using the outcomes of the Ōtaki to North of Levin Scoping Report and addendum, the NZTA decided that the most appropriate strategy for the highway between Ōtaki and north of Levin is to upgrade the existing highways as the first stage of a long term strategy. This allows the NZTA to realise important safety benefits in the short to medium term whilst deferring the need to construct four lanes for the time being.
This Project Feasibility Report (PFR) is one of a number of reports being undertaken to determine the package of improvements that should be implemented to improve the safety and efficiency of the highway between Ōtaki and north of Levin as part of the Wellington Northern Corridor Road of National Significance (RoNS).
The objectives of the Wellington Northern Corridor RoNS, which runs from Wellington Airport to north of Levin, are:
To enhance inter regional and national economic growth and productivity;
To improve access to Wellington’s CBD, key industrial and employment centres, port, airport and hospital;
To provide relief from severe congestion on the state highway and local road networks;
To improve the journey time reliability of travel on the section of SH1 between Levin and the Wellington Airport; and
To improve the safety of travel on state highways.
For the Ōtaki to north of Levin section; the objectives are:
To provide best value solutions which will progressively meet (via a staged approach) the long term RoNS goals for this corridor of achieving a high quality four lane route;
To provide better Levels of Service, particularly for journey time and safety, between north of Ōtaki and north of Levin;
To remove or improve at-grade intersections between north of Ōtaki and north of Levin;
To engage effectively with key stakeholders; and
To lodge Notices of Requirement and resource consents as appropriate with the relevant consent authorities for the first individual project by the 2013/14 financial year.
The projects that are being developed to help meet these objectives are presented in Section 2.
The purpose of this report is to determine the feasibility of undertaking safety improvements on the section of State Highway 1 through the Forest Lakes area.
The improvements proposed for Forest Lakes differ to those previously investigated as the current proposal seeks to adopt RoNS guidelines for geometric alignment and cross section. It also takes into account the need for a safe transition from the Peka Peka to Ōtaki project which ends just north of Taylors Road; 1 km further north than the previous southern extent of the Forest Lakes projects.
The geographical extent of this project is from immediately north of Taylors Road in the south to immediately south of the Pukehou Rail Overbridge in the north, a length of approximately 2.8 km.
The outcome of this PFR will be considered alongside the outcomes of the other PFRs and used to determine the best package of works to progress as the first stage of the long term strategy.
2 Projects Currently Being Investigated The projects that are currently being investigated to meet the short to medium term objectives of the Ōtaki to north of Levin RoNS project are presented in the figure below.
Report 1: Forest Lakes Projects Currently Being Investigated
Status: Final April 2013 Project number: Z1925700 Page 2 Our ref: PFR01 Forest Lakes Final v2.docx
Figure 2-1: Projects Currently Being Investigated
In addition to the above PFRs, reports are also being undertaken on Route Improvem ents (i.e. edge treatment, passing lanes, walking and cycling, side friction etc; Report No. 11) and on Four Lane Alignments (Report No.12).
Foxton
Levin
Ohau
Manakau
Otaki
1. Forest Lakes
2. Manakau
Settlement
3. Manakau to
Ohau
4. Ohau
Settlement
5. SH1 & SH57
Connection
6. Heavy Vehicle
Bypass
7. Levin Signals
10.Queen St
Intersection
8. Waitarere Beach
Road Curves
9. Whirokino
Trestle
Report 1: Forest Lakes Description of Problem
Status: Final April 2013 Project number: Z1925700 Page 3 Our ref: PFR01 Forest Lakes Final v2.docx
3 Description of Problem
3.1 Ōtaki to North of Levin
State Highway 1 and State Highway 57 through the study area have a number of deficiencies, resulting in a poor crash history and a number of locations where the free flow of vehicles is restricted by the physical characteristics of the highway.
State Highway 1 currently follows the historic route established in the late 19th
and early 20th
centuries. As a consequence it is constrained by a now substandard alignment, towns and settlements, narrow curved bridges and significant side friction caused by local roads, commercial frontages and property accesses for the entire stretch.
3.2 Forest Lakes
The section of road through Forest Lakes has had a high number of crashes in recent years. Of particular concern are the run-off-road and cross-centreline crashes, due to their severe nature.
Key safety and alignment deficiencies for the Forest Lakes section, determined through site inspections and previous reports are presented below.
No median barrier – Austroads and NZTA guidance indicates that a median barrier should be provided when there is a high percentage or high average daily number of heavy vehicles, or severe consequences for vehicles crossing the centreline.
Narrow carriageway – lanes are below the desirable 3.5 m width.
Substandard shoulder widths – shoulders are generally below the 1.5 m NZTA link criterion and the desirable RoNS standard of 2.5 m, which is concern for loss of control crashes as well as for cyclists.
Inconsistent clear zone and a large number of accesses with resultant side friction concerns.
Inconsistent speed environment and out of context curves – two curve are below the standard required for a 100 km/h highway.
Substandard combinations of vertical and horizontal curves.
In addition, no right turn bays are provided at the side roads or at the two rest areas.
The above deficiencies are considered to have contributed to the high number of injury crashes on this section of highway.
4 Site Description The project area consists of a 2.8 km section of SH1 from just south of Pukehou Rail overbridge (RP 995/0.25) to north of Taylors Road (RP 995/3.05), where this project ties in with the Peka Peka to Ōtaki (PP2O) RoNS project.
The section of road is a two lane undivided carriageway with passing lanes. Lane widths are typically below 3.5 m and shoulder widths vary along the length. The posted speed limit is 100 km/h with terrain that is generally flat to rolling.
Figure 4-1 below shows the study location.
Report 1: Forest Lakes Site Description
Status: Final April 2013 Project number: Z1925700 Page 4 Our ref: PFR01 Forest Lakes Final v2.docx
Figure 4-1: Study Area Location Map
There are two side roads that intersect the state highway along the study length being Forest Lakes Road at RP 995/1.2 and Lawlors Road
1 at RP 955/2.6. Taylors Road intersects just south of the study
area at RP 995/3.3. In addition to the side roads, there are a number of private properties that gain access directly from the state highway.
Other features along the project length include:
Two rest areas;
o A rest area for northbound traffic at RP 995/0.7 on the western side
o A rest area for southbound traffic at RP 995/2.0 on the eastern side
Two passing lanes, both short compared to current standards;
o A northbound passing lane from RP 995/0.8 to RP 995/1.8
o A southbound passing lane from RP 995/1.9 to RP 995/3.0
Five horizontal curves along the project area including;
o Northbound rest area curve – 1250 m radius, left hand curve
o Southbound rest area curve – 600 m radius, right hand curve
o Curve south of Lawlors Road – 1000 m radius, left hand curve
o Curve between Lawlors Road and Taylors Road – 425 m radius, left hand curve
o In addition, just to the north of the study area is Pukehou Rail Overbridge curve – 450 m radius, right hand curve (not in project extent)
A number of vertical curves (these are discussed in the Ōtaki to Levin Route Improvements Report)
The North Island Main Trunk (NIMT) rail line runs predominantly parallel to SH1. The rail line crosses under SH1 at the northern end of the study area via the Pukehou Rail Overbridge.
There are currently no pedestrian walkways or cycle lanes along this section of SH1.
1 Lawlors Road provides access to only three properties, of which only one has a dwelling. The road
reserve width is only 5 m, with the sealed carriageway being around 3 m.
To Manakau
To Ōtaki
Lawlors Rd
Forest Lakes Rd
Taylors Rd
Pukehou Rail overbridge
N
Rest Areas
Passing Lanes
Report 1: Forest Lakes Traffic Statistics
Status: Final April 2013 Project number: Z1925700 Page 5 Our ref: PFR01 Forest Lakes Final v2.docx
The surrounding land through Forest Lakes primarily consists of farm land. To the north of Forest Lakes Road is an area of 2.1 hectares of Kohekohe-Mahoe forest, which is an area of indigenous vegetation protected under the Kapiti Coast District Plan.
Other special features identified during the constraint mapping undertaken as part of the Ōtaki to North of Levin Scoping Report include:
Historic Maori Site of Pukehou Hill;
Queen Elizabeth II covenant protected wetlands opposite the southbound rest area; and
Forest Lakes Camping and Conference Centre located on Forest Lakes Road.
5 Traffic Statistics The Annual Average Daily Traffic (AADT) flow at the NZTA count site North of the Waitohu Stream Bridge (ID: 01N00998) was 13,900 vehicles per day (vpd), 2011, with the proportion of Heavy Commercial Vehicles (HCVs) at 11%.
The traffic growth rate at the site is estimated to be 1.3% based on the Ohau Telemetry Site, using data from 1992 to 2011. Volumes typically increased from 2000 to 2010; however this trend has not carried through to 2011.
Side road traffic volumes were obtained from the CAS and RAMM databases and are as follows:
Taylors Road: 250 ADT (2002 Estimate)
Lawlors Road: None available but estimated at less than 20 vpd.
Forest Lakes Road: 180 ADT (2010 Count)
The Ōtaki to north of Levin SATURN base network model outputs2 showing link Level of Service (LoS)
and intersection LoS for 2011 and 2041 are outlined in Table 5-1. The model did not include intersection nodes for Forest Lakes Road or Lawlors Road but did include Taylors Road, which is included for reference purposes in the table below.
Table 5-1: Saturn Base 2011/2041 Network Modelling Results
Year Link LoS Taylors Road* Intersection
Worst Movement LoS
2011 AM A/B A/B
2011 IP A/B A/B
2011 PM A/B C
2041 AM A/B D
2041 IP A/B C
2041 PM A/B F
*Note this project starts just north of Taylors Road.
Further traffic information can be found in Appendix B.
2 See Ōtaki to north of Levin Scoping Report
Report 1: Forest Lakes Crash History
Status: Final April 2013 Project number: Z1925700 Page 6 Our ref: PFR01 Forest Lakes Final v2.docx
6 Crash History
6.1 Crash Data
A review of NZTA’s CAS database over the five-year period from July 2007 to June 2012 revealed a total of 20 crashes along the 2.8 km section of highway (SH1 RP 995/0.25 – RP 995/3.05).
The following tables provide a summary of the CAS output data.
Table 6-1: Annual Distribution of Crashes
Year Fatal Serious Minor Non-Injury Total DSi*
July - Dec 2007 - - - - - -
2008 - - 1 3 4 -
2009 - 2 4 1 7 3
2010 - 1 1 2 4 1
2011 - 1 1 1 3 1
Jan – June 2012 - 1 0 1 2 1
Total - 5 7 8 20 6
* Death and serious injury casualties
It is noted that this site does have a history of fatal and serious crashes outside of the five year period, with two fatal and one serious crash occurring in 2005 and 2006. No specific changes have been made at the site since this time so there is a risk of further fatal crashes occurring. The previous scoping report outlined six fatal and serious crashes in the 5 year period which is not inconsistent with the five shown above.
Table 6-2: CAS Crash Type
Crash Type Number of Reported
Crashes Percentage of Reported
Crashes
Overtaking Crashes 4 20%
Straight Road Lost Control/Head On 1 5%
Bend – Lost Control/Head On 8 40%
Rear End / Obstruction 5 25%
Crossing / Turning 1 5%
Pedestrian Crashes - 0%
Miscellaneous Crashes 1 5%
Total 20 100%
Report 1: Forest Lakes Crash History
Status: Final April 2013 Project number: Z1925700 Page 7 Our ref: PFR01 Forest Lakes Final v2.docx
Table 6-3: HRRRG3 Crash Type
Crash Type Number of Reported
Crashes DSi Percentage of
Reported Crashes
Head on 1 0 5%
Run off Road 10 1 50%
Intersection Crashes 4 3 20%
Other 5 2 25%
Total 20 6 100%
Table 6-4: Crash Causation Factors of Reported Injury Crashes
Causation Number of Reported Injury Crash Causation
Factors
Alcohol 1
Too fast 3
Failed giveway/stop 2
Overtaking 2
Incorrect lane/position 3
Poor handling 8
Poor observation 5
Poor judgement 6
Fatigue 4
Vehicle factors 4
Road factors 1
Weather 2
Other 1
Table 6-5: Environmental Factors
Wet Dry Night Day Weekend (Fri 6:00PM to
Monday 5:59AM) Weekday
No. 6 14 6 14 5 15
% 30 70 30 70 25 75
Of the crashes occurring on this 2.8 km section of SH1:
None were fatal, five were serious, seven were minor and eight were non-injury.
10 (50%) involved run-off road movements resulting in one serious and six minor injury crashes (1 DSi).
1 (5%) was a head on minor injury crash, caused by fatigue.
4 (20%) were intersection related crashes resulting in 2 serious, 1 minor and 1 non-injury crash (3 DSi).
3 High Risk Rural Roads Guide (HRRRG), NZTA, September 2011
Report 1: Forest Lakes Alternatives and Options Considered
Status: Final April 2013 Project number: Z1925700 Page 8 Our ref: PFR01 Forest Lakes Final v2.docx
5 (25%) crashes were movement codes classed as ‘Other’. including two serious injury crashes. These involved a rear end with an object and a trailer loss of control.
5 (25%) were rear end crashes resulting in two serious injury crashes, one minor and two non-injury. All of the injury rear end crashes occurred due to a southbound vehicle colliding with a vehicle turning right into Forest Lakes Road.
The percentage of wet and night crashes are similar to the network average of approximately 30%.
14 (70%) crashes involved vehicles crossing the centreline; either losing control, overtaking or crossing/turning. This included four of the five serious injury crashes and 6 minor injury crashes.
2 minor injury crashes, including a head-on and a loss of control while turning, occurred on the curve north of Taylors Road.
The main crash causation factors included poor judgement, poor handling, poor observation, and incorrect lane position.
10 crashes involved objects being struck; e.g. cliff, bank, ditch, tree etc.
Historically there have been several fatal crashes within the study area:
In 2005, a southbound crossed the centreline whilst avoiding another vehicle, pulling into the passing lane, and hits a northbound vehicle head on, resulting in 3 DSI.
In 2006, a northbound vehicle lost control while returning from the sealed unsealed shoulder an d crossed the centreline and was hit head on, resulting in 3 DSI.
6.2 Crash Risk
The section of SH1 was analysed according to the High-Risk Rural Roads Guide (HRRRG) which identifies that crash risk can be generally defined in two ways:
Actual Crash Risk; which is based on crashes reported in the last 5 years. This is separated into collective risk, which is also known as crash density, and personal risk, which is also known as crash rate.
Predicted Crash Risk; which is based on KiwiRAP road protection score (RPS) and the KiwiRAP star rating.
In terms of crash risk this 2.8 km section of SH1 from north of Taylors Road to Pukehou Overbridge has:
A collective risk of 0.36 high-severity (fatal and serious) crashes per km per year;
A personal risk of 7.02 high-severity crashes per 100 million vehicle km; and
An average KiwiRAP star rating of 3.1, giving a published KiwiRAP rating of 3 stars.
The personal risk value equates to the highway having a medium-high risk. In addition, the collective risk was calculated as high and therefore this means this length of SH1 is classified a high-risk rural road.
Typically a 5 km highway with Star Rating of 3.1 would expect a crash rate of 17.5 injury crashes per 100 million vehicle km, based on Figure C-2 of the HRRRG.
Further Crash Data can be found in Appendix C.
7 Alternatives and Options Considered Two options have been considered for the section of SH1 from north of Taylors Road to just south of the Pukehou Rail Overbridge with the main aim of improving safety. Both options considered include a NZTA Test Level 4 (TL4) wire rope median barrier (WRB), shoulder widening, curve realignment. The
Report 1: Forest Lakes Alternatives and Options Considered
Status: Final April 2013 Project number: Z1925700 Page 9 Our ref: PFR01 Forest Lakes Final v2.docx
options also both involve removal of the northbound and southbound passing lanes as the PP2O project to the south provides passing opportunities.
The Do Minimum has been assumed to be the continued maintenance and operation of the existing highway.
The two options considered are:
Option 1-1: Desirable RoNS Standard – WRB, wide median and a realignment of the curve north of Taylors Road to a radius of 1100 m.
Option 1-2: Absolute Minimum RoNS Standard – WRB, narrow median and a realignment of the curve north of Taylors Road to a radius of 550 m.
7.1 Option 1-1: Desirable RoNS Standard
This option is put forward as the most desirable option when consideration of RoNS design standards are taken into account.
A typical cross section of the 18 m carriageway (16 m seal including median) is shown in Figure 6-1 below.
Figure 7-1: Option 1 Typical Section – Desirable RoNS Standard
The option consists of:
Two 3.5 m lanes;
Two 2.5 m shoulders;
4.0 m median with WRB; and
Realignment of the curve north of Taylors Road to 1100 m radius (110 km/h design speed).
The option will upgrade the existing two lane undivided carriageway with passing lanes to a two lane divided carriageway with a 4.0 m wide median and 2.5 m sealed shoulders. The option also includes the realignment of a left hand curve between Taylors Road and Lawlors Road from 425 m radius to 1100 m. No other realignments were considered due to the Peka Peka to Ōtaki RoNS coming in at Taylors Road.
This width provided by this option means that it has the potential to be changed to a 2+1 arrangement in the future with reduced shoulder and median width without widening the carriageway. The potential 2+1 lane arrangement is as follows:
1.5 m shoulder, two 3.5 m lanes, 1.5 m median, one 3.5 m lane, 2.5 m shoulder.
7.2 Option 1-2: Absolute Minimum RoNS Standard
This option retains a similar form to Option 1 with a WRB and shoulder widening; however, Option 2 has a narrower median and a smaller radius curve realignment, resulting in a lower cost.
A typical cross section of the 15.5 m carriageway (13.5 m seal including median) is shown in Figure 6-2 below.
Report 1: Forest Lakes Alternatives and Options Considered
Status: Final April 2013 Project number: Z1925700 Page 10 Our ref: PFR01 Forest Lakes Final v2.docx
Figure 7-2: Option 2 Typical Section – Compromised RoNS Standards
The option consists of:
Two 3.5 m lanes;
Two 2.5 m shoulders;
1.5 m median with WRB; and
Realignment of the curve north of Taylors Road to a 550 m radius.
The option will upgrade the existing two lane undivided carriageway to a two lane divided carriageway with a narrow 1.5 m median and 2.5 m sealed shoulders. The option also includes the realignment a left hand curve between Taylors Road and Lawlors Road from 425 m radius to 550 m. No other curve improvements were required.
Unlike Option 1-1, this option cannot be upgraded to a 2+1 configuration in the future wi thout further carriageway widening.
Both Options 1-1 and 1-2 have been brought forward for assessment to determine the most viable solution.
7.3 Other Aspects
7.3.1 Passing Lanes
The current options assume that the passing lanes will be removed as they would be in close proximity to the new four lane section of Peka Peka to Ōtaki. However, this needs to be confirmed with the passing lane strategy for Ōtaki to Levin which is being undertaken concurrently with this PFR. Costs and Benefits of the passing lanes have been discussed in Report 11, Route Improvements.
7.3.2 Other Curves
This PFR has only considered improving the curve immediately north of the Peka Peka to Ōtaki project to improve the transition from the expressway onto the two lane highway. However, it is noted that there is one other curve with a radius between 550 m and 1100 m within the project extents (at the southbound rest area) which could be upgraded as part of Option 1-1. (The other curve with this criterion, the curve south of Lawlors Road, is encompassed by the curve realignment in Option 1-1)
Furthermore, the curve at Pukehou Rail Overbridge has a radius of only 450 m. Whilst this is outside of the project extent, it is noted that this is below the RoNS absolute minimum radii and would need to be addressed as part of the overall strategy between Ōtaki and north of Levin.
7.3.3 Rest Areas
No changes are proposed to the existing rest areas.
7.3.4 Edge Barrier
Edge barrier is currently proposed as they are more effective than clear zones at reducing fatal and serious crashes. Further investigation will be required at the next stage of investigation to determine the most appropriate treatment taking into account crash savings, cost, future proofing, accessways, turning areas, location and frequency of hazards etc.
Report 1: Forest Lakes Design Statement
Status: Final April 2013 Project number: Z1925700 Page 11 Our ref: PFR01 Forest Lakes Final v2.docx
7.3.5 Accessways and Intersections
It is acknowledged the wire rope barrier will result in drivers not being able to turn right into or out of adjacent properties and therefore these drivers will attempt to turn around at either end of the wire rope.
It is currently considered that turn around facilities will need to be provided at Taylors Road and at a point north of the end of the wire rope barrier in the vicinity of the Pukehou Bridge. At this stage no attempt has been made to determine the best location and form of turn around facilities for these movements, but an allowance has been made for them in the cost estimate.
No decision has been made as to the form of intersection treatment at Forest Lakes Road, Lawlors Road or Taylors Road, including whether the wire rope barrier will continue through the intersections.
8 Design Statement This project is at a feasibility stage, and therefore several assumptions have been made in the design.
The design assumptions include the following:
The cost estimate has been based on the judgement of an engineer who has knowledge of the site.
The cost estimate has been based on the assumption that the project can be built using proven technology.
No adverse ground conditions are encountered (e.g. contaminated material or large areas of peat).
Regrading the carriageway would not be required but new surfacing would be laid across the entire width and length of the project.
Earthwork batter slopes are assumed to be 3H:1V for fills and 2H:1V for cuts. Barrier side protection, rather than clear zones, has been allowed for. Further investigation will be undertaken at Scheme Assessment phase to determine the extent of side protection barriers versus clear zones. Earthwork extents have been estimated as no topographical survey data is available.
It has been assumed that the existing carriageway will largely be retained. A nominal 100 mm of overlay has been allowed for to correct any existing rutting or provide shape correction as required. Where the carriageway requires widening (i.e. to provide a median and shoulder) or the highway is being realigned, construction will take the form of cement modified granular pavement. In lieu of geotechnical testing the depth of pavement construction has been based on local knowledge and typical sections provided for RoNS projects to the south. This allows for 350 mm of sub-base, and 300 mm of cement modified base-course with a chip seal surface.
9 Cost Estimates The expected and 95
th percentile estimates for the options are detailed in Table 9-1 below.
Table 9-1 : Cost Estimate
Option Description Expected Estimate 95th Percentile Estimate
Option 1-1 – Desirable RoNS Standards
$14,000,000 $18,000,000
Option 1-2 – Compromised RoNS Standards
$11,400,000 $14,600,000
The cost estimates for the options have been calculated using concept layouts of the options and with no survey data, and are based on the design statement assumptions as listed above. The cost estimates for the options are given in Appendix E.
Report 1: Forest Lakes Economic Assessment and Risk Assessment
Status: Final April 2013 Project number: Z1925700 Page 12 Our ref: PFR01 Forest Lakes Final v2.docx
The estimates are significantly higher than the estimates previously presented under the Forest Lakes Scoping Report
4. The main reason for this is the adoption of the higher RoNS standards. The largest
differences are outlined below:
Realignment of the curve north of Taylors Road which requires new carriageway construction for 800 m in Option 1-1 and 400 m in Option 1-2.
Additional carriageway width; the typical cross sections of the two current options are 18 m and 15.5 m compared to the preferred option in the previous report of 12.5 m
The current options provide for edge protection in the form of guardrail, (as opposed to wire rope which maybe more appropriate and will be considered during the scheme design).
It is noted that the removal of the passing lanes results in additional carriageway width becoming available; however with the southbound passing lane in particular, this occurs around the realigned curve so this carriageway width unable to be utilised.
10 Economic Assessment and Risk Assessment
10.1 Basis of Economic Analysis
Economic analysis was carried out in accordance with NZTA’s Economic Evaluation Manual (EEM) using a modified version of the simplified procedures.
The following assumptions have been made in the calculation of the Benefit Cost Ratio. They are:
1. The base year is 2012 and time zero is 2013.
2. Time zero AADT along this section of road is projected to be approximately 15,700 vehicles per day (2013) and annual traffic growth is estimated as 1.3 %.
3. The crash analysis has been done for the five calendar year period July 2007 – June 2012 and considers the following:
a. Accident by accident Analysis – based on Method A of the EEM as there are more than three injury crashes per km and there will be no fundamental change at the site.
i. Cross Centreline Crashes:
1. Crashes affected by the median barrier are those where the centreline was crossed – these typically resulted in head-on collisions or the vehicle leaving the road on the opposite side to which it was travelling.
2. The crashes that crossed the centreline were determined from inspection of the Police Traffic Crash Report, attached in Appendix C.
3. It has been assumed that after installation of the barrier all fatal and serious crashes affected by the median barrier will be reduced by 90%. This figure is taken from the 2003 Austroads Guide to Traffic Engineering Practice, Part 4.
4. It is assumed that there will be a 30% increase in non-injury crashes and no decrease in minor injury crashes.
ii. Intersection Crashes:
1. It has been assumed that intersection crossing/turning crashes will be reduced by 75% as the WRB will prevent right turns in and out of Forest Lakes Road. In addition, right turn bays and turnaround areas will most likely be provided at Taylors Road and Pukehou which will provide safer side road access.
4 Beca, April 2010
Report 1: Forest Lakes Economic Assessment and Risk Assessment
Status: Final April 2013 Project number: Z1925700 Page 13 Our ref: PFR01 Forest Lakes Final v2.docx
2. This figure is taken from the EEM Volume 1.
iii. Loss of Control Crashes:
1. It has been assumed that loss of control crashes, which did not cross the centreline, will be reduced by 10% due to the WRB and median width enabling greater vehicle recovery time.
b. Shoulder and Carriageway Widening
i. Accident rate analysis was used to determine the crash benefits from widening the carriageway for the route length.
ii. The analysis was based on the weighted accident procedure (Method C) for both the do-minimum and the option.
iii. Since the EEM accident modification factors do not extend beyond a 2.0 m shoulder, we have conservatively assumed that the 2.5 m shoulder benefits are the same as a 2.0 sealed shoulder.
c. Curve Realignment
i. The curve realignment is based on Method C for the do-minimum and the option as the curve is less than 1 km in length, has fewer than five injury crashes and the curve realignment is not a fundamental change.
ii. The analysis uses the following assumptions for curve design speed and approach speed.
1. Existing Curve Design Speed 85 km/h:
a. Approach speed in the increasing direction 110 km/h (due to the existing passing lane).
b. Approach speed in the decreasing direction 100 km/h.
2. Option 1 Curve Design speed 110 km/h:
a. Approach speed in the increasing direction 100 km/h.
b. Approach speed in the decreasing direction 110 km/h (assumes PP2O constructed).
3. Option 2 Design speed 100 km/h:
a. Approach speed in the increasing direction 100 km/h.
b. Approach speed in the decreasing direction 110 km/h (assumes PP2O constructed).
4. The 2011 update factors and a discount rate of 8% have been used.
A summary of the economic analysis is detailed in the sections below.
10.2 Travel Time Savings
As the curve radius and vehicle operating speeds for the proposed options for realignment at this curve are negligible the net travel time savings are not expected to alter the option BCR. The benefits are greatest for Option 1-2 and are in the order of $500,000. Travel time benefits will be examined and included for options advanced during SAR.
10.3 Vehicle Operating Cost Savings
With a small decrease in distance travelled, and a minor increase in vehicle speeds it is expected that there will be a small (less than $100,000) disbenefit for vehicle operating costs. Vehicle operating c osts will be examined and included for options advanced during SAR.
Report 1: Forest Lakes Economic Assessment and Risk Assessment
Status: Final April 2013 Project number: Z1925700 Page 14 Our ref: PFR01 Forest Lakes Final v2.docx
10.4 Crash Benefits
The installation of a median barrier is expected to reduce the severity of fatal and serious crashes which involve vehicles crossing the centreline. Intersection crossing/turning crashes are expected to reduce as a result of the WRB preventing right turns in and out of Forest Lakes Road, with right turn bays and turnaround areas being provided along the project area to enable safe and efficient side road access. In addition, carriageway widening and the realignment of the curve north of Taylors Road are also expected to reduce the number of crashes along this section of SH1.
The expected accident cost savings are shown in the Table 9-1 below.
Table 10-1: Crash Benefits
Option Accident Cost Savings (NPV)
Option 1-1 – Desirable RoNS Standards $17,400,000
Option 1-2 – Absolute Minimum RoNS Standards
$16,800,000
The difference in crash benefits between the options is solely attributed to due to the increased designed speed of Option 1’s 1100 m radius curve realignment resulting in greater accident cost savings when compared to Option 2’s 550 m radius curve.
The difference in median width is not recognised in the EEM and the same reduction in crash severity arising from the WRB has been used for both options.
10.5 Maintenance Costs
Existing maintenance costs have not been included, as the majority of these should remain unchanged. Therefore, only maintenance costs associated with the barrier itself and the costs of additional carriageway width have been included in the analysis.
The additional carriageway costs have been based on rates of $25 /m2 for asphalt (OGPA) and $4.5 /m
2
for chip seal surfacing.
Barrier maintenance costs have been estimated by using costs associated with the Centennial Highway (Coast Road) Wire Rope Median Barrier and adjusting for the length of barrier. This has been estimated at $20,000 /year for Option 2 and a reduced $15,000 /year for Option 1 to account for the wider median. This is conservative as the tight geometric constraints on the coastal section of Centennial Highway would be expected to have a greater number of hits than the section of road covered by this project.
10.6 Benefit Cost Ratio Results
Table 10-2: Economic Analysis Summary
Option Description Total Cost (NPV) Total Benefits (NPV) BCR
Option 1-1 – Desirable RoNS Standards
$15,155,000 $17,428,000 1.2
Option 1-2 –Compromised RoNS
Standards
$12,417,000 $16,812,000 1.4
Option 1-1 has higher total benefits than Option 1-2, however due to the increased costs, Option 2 has a higher BCR of 1.4.
Incremental BCR analysis shows that Option 1-2 is the preferred option in economic terms.
Report 1: Forest Lakes Assessment Profile
Status: Final April 2013 Project number: Z1925700 Page 15 Our ref: PFR01 Forest Lakes Final v2.docx
10.7 Risk Assessment
The risks to the project have been assessed using the General Approach as determined in the NZTA Risk Management Process Manual (AC/Man/1).
The major potential risks associated with the Forest Lakes improvement project are considered to be:
Project unable to get funded due to constrained funding environment.
Local opposition to the project primarily due to wire rope barrier restricting access to properties and side roads.
Inaccurate cost estimate due to level of available data at this feasibility state, including utility information and assumptions in regards to passing lanes, turn around areas and seal type.
Increased delays to traffic arising from maintenance / strikes on the wire rope barrier.
Increased response times for emergency vehicles.
Traffic delays during construction.
Environmental effects during construction.
Impacts on existing services.
Land acquisition difficulties.
Difficulties in obtaining resource consents and/or alteration to designation.
Opposition from local iwi.
Additional landowner accommodation works required.
Project scope increase to a 2+1 or four lane solution.
11 Assessment Profile The Government Policy Statement on Land Transport Funding (GPS) requires the NZTA to consider a number of matters when evaluating projects. To assist in understanding how projects perform against these matters and hence what investment decisions to make, the NZTA utilises an assessment profile process.
The assessment profile is a three-part rating for an activity, rated as high, medium or low e.g. HMM, and representing the assessment for Strategic Fit, Effectiveness and Efficiency respectively.
It is considered that the assessment profile5 for Forest Lakes is HHL. The following paragraphs outline
how this profile has been created.
11.1 Strategic Fit
The strategic fit factor is a measure of how an identified problem, issue or opportunity that is addressed by a proposed activity or combination of activities, aligns with the NZTA’s strategic investment direction.
As this project is part of a Road of National Significance and is classified as a High Risk Rural Road, the Strategic Fit is High.
11.2 Effectiveness
The effectiveness factor considers the contribution that the proposed solution makes to achieving the potential identified in the strategic fit assessment and to the purpose of the Land Transport Management Act (LTMA).
5 NZTA Planning and Investment Knowledge Base, www.pikb.co.nz/assessment-framework
Report 1: Forest Lakes Social and Environmental Assessment
Status: Final April 2013 Project number: Z1925700 Page 16 Our ref: PFR01 Forest Lakes Final v2.docx
A wide range of assessment factors are available for use in this effectiveness rating and these draw from the five LTMA areas of:
Economic Development
Safety and Personal Security
Access and Mobility
Public Health
Environmental Sustainability
A number of other key criteria need to be considered including integration, consideration of options and responsiveness.
As this project is part of the Roads of National Significance programme, it is recommended that the effectiveness factor for RoNS projects of High is adopted.
This is considered appropriate as the project will contribute positively to safety and is consistent with NZTA’s strategies and plans.
11.3 Efficiency
The economic efficiency assessment considers how well the proposed solution maximises the value of what is produced from the resources used. This is primarily undertaken by the Benefit Cost Ratio.
As this project has a BCR of between 1 and 2, the efficiency rating is Low.
12 Social and Environmental Assessment The Scoping Report phase of the Ōtaki to Levin RoNS and the previous Scoping Report for Forest Lakes have identified a number of social and environmental factors which will need to be assessed during any scheme assessment phase. These are outlined below.
An area of 2.1 hectares of Kohekohe-Mahoe forest immediately north of Forest Lakes Road, an area of indigenous vegetation protected under the Kapiti Coast District Plan;
Historic Maori Site of Pukehou Hill (see photo in Attachment B) located to the east of the highway;
Potentially nationally significant wetlands between Lawlors Road and Forest Lakes Road on the western side of the highway. This includes an area of Queen Elizabeth II covenant protected wetlands opposite the southbound rest area;
Some Maori owned land is present on both sides of the current highway;
Potential for flooding in the vicinity of Taylors Road; and
Forest Lakes Camping and Conference Centre located on Forest Lakes Road.
Consultation has been carried out under the scoping phase of the Ōtaki to north of Levin RoNS and on-going consultation will continue with stakeholders throughout the planning and design process. The area is identified as being of cultural importance to the iwi of Rangitane o te Whanganui a Tara, Ngati Raukawa ki te Tonga and Ngati Toa Rangitira.
A Consultation Plan for the entire Ōtaki to north of Levin project and consultation will be undertaken in accordance with the plan. The purpose of the plan is to:
Provide a documented process for intended engagement with the community, including the
project context, the parties involved, and desired outcomes;
Maximise effective and efficient engagement of community within generally tight time
constraints;
Provide the specifics of consultation to be undertaken, including timeframes;
Help the project team to proactively manage risks to the project/project future from inappropriate
or inadequate community engagement; and
Help the project team to constructively manage community expectations.
Report 1: Forest Lakes Geotechnical Requirements
Status: Final April 2013 Project number: Z1925700 Page 17 Our ref: PFR01 Forest Lakes Final v2.docx
13 Geotechnical Requirements A preliminary geotechnical appraisal report for the previous Forest Lakes Scoping Report was prepared by MWH in 2011. This report outlined that the majority of the stretch of the highway is underlained by beach deposits (Ōtaki Sandstone). To investigate the subsurface conditions along the alignment, MWH recommended field investigations consisting of hand-auger bores, boreholes, test pits, and Cone Penetration Tests (CPT) depending on the location of proposed embankments and retaining walls.
The preliminary geotechnical appraisal report for the Ōtaki to Levin RoNS noted the following aspects in regards to the Forest Lakes section:
It has moderate to high settlement potential;
It has a seismic potential due to the proximity of the active Northern Ohariu Fault;
It has low to moderate susceptibility to liquefaction; and
A small area is within the tsunami influence zone being less than 10m above sea level.
14 Land Requirements Option 1-1 requires land to be purchased from 23 separate appellations. Option 1 would also require the demolition of an existing farm house and complete acquisition of the dwelling ’s land in order to realign the curve north of Taylors Road to a radius 1100 m. In total, Option 1 requires approximately 45,000 m2 of land.
Option 1-2 requires land to be purchased from 17 separate appellations. The realignment of the curve north of Taylors Road to radius 550 m is more closely aligned to the existing highway, and requires less land be purchased. It also negates the need to demolish any exist ing dwellings. Option 2 requires a total of approximately 18,800 m2 of land to be purchased.
15 Resource Management Issues The project must meet all statutory requirements. There are a number of documents (both statutory and non-statutory) that must be considered when planning for the state highway improvements. In particular, the requirements of the Resource Management Act, the Kapiti Coast District Plan and the Wellington Regional Plans will be assessed to ensure that the proposed project meets the plan provisions and follows the statutory process.
15.1 District Plan Provisions
15.1.1 Designation
The section of SH1 is designated under the Kapiti Coast District Plan for “state highway purposes” (D0101). The existing designation is narrow in places and may need to be altered to accommodate the proposed road improvements.
Both the options require the utilisation of land immediately adjoining the existing designation, Accordingly, it is recommended that the designation boundaries be altered to accommodate these works under s181 RMA. NZTA will be required to give notice to the Council of its requirement to alter the designation (NOR). Alternatively, NZTA could apply for a resource consent ( land use consent) to carry out the proposed works outside the designation.
15.1.2 Heritage Issues
The Heritage Register identifies an area of indigenous vegetation in the vicinity of the proposed works. The Kohekohe-Mahoe forest is protected under the District Plan (K151). The 2.1 ha area is a small fragmented area of kohekohe-mahoe forest with considerable weed threat. It is described as having “Significance” in the District given that indigenous vegetation on alluvial plain is nationally under -
Report 1: Forest Lakes Maintenance Issues
Status: Final April 2013 Project number: Z1925700 Page 18 Our ref: PFR01 Forest Lakes Final v2.docx
represented. Black beech is also present (uncommon in the Ecological District). Pukehou Swamp (K013 ) is identified on the District Plan and is also a site of “Significance” in the vicinity of the proposed works.
The Heritage Register also identifies the sign erected showing the site of the overnight camp of Mua Upoko fleeing from Te Rauparaha (B70).
15.1.3 Natural Hazards
There is the potential for flooding in the vicinity of Taylors Road, however the proposed works do not fall within the area identified in the Natural Hazards Maps.
15.2 Regional Plans
The final designs and construction plans will determine what regional consents are required. There are a number of culverts and small streams flowing underneath SH1 in the vicinity of the proposed works, and some of the works will involve cut slopes requiring earthworks.
The following resource consents are likely to be required under the Wellington Regional Plans:
Stormwater discharges from bulk earthworks under the Regional Freshwater Plan;
Soil and vegetation disturbance on erosion prone land, and road and tracking activities under the Regional Soil Plan;
Discharges of contaminants to land under the Regional Plan for discharges to land; and
Discharge of contaminants to air from road construction under the Regional Air Quality Management Plan.
16 Maintenance Issues The current proposals would result in two specific changes to the maintenance regime:
maintenance and repair of the wire rope median barrier; and
maintenance of an asphaltic surfacing rather than chip seal.
Both these aspects have been included in the economic evaluations of the options.
17 Conclusions and Recommendations The installation of a wire rope median barrier (WRB) is expected to reduce the severity of all injury crashes which involve vehicles crossing the centreline. Intersection crossing/turning crashes are expected to reduce as a result of the WRB preventing right turns in and out of Forest Lakes Road, with right turn bays and turnaround areas being provided along the project area to enable safe and efficient side road access. In addition, carriageway widening and the realignment of the curve north of Taylors Road are also expected to reduce the number of crashes along this section of SH1.
The installation of a wire rope median barrier with a single lane in each direction could create potential issues for the efficient operation of the highway, maintenance works and access to incidents. It is likely to restrict access for emergency and other vehicles during an incident , which would result in additional travel for emergency response vehicles. However, this will be mitigated by the wide 2.5 m shoulders of both options and the wider 4 m median of Option 1-1.
The carriageway widening, curve realignment and installation of a wire rope barrier through Forest Lakes provides significant crash cost savings, achieving a Benefit Cost Ratio of 1.4 for Option 1-2.
It is recommended that Option 1-2 be the preferred option at this location due to the significant safety benefits. However, this option needs to be considered in light of the short medium and long term strategy for this section of highway which is being developed concurrently with this PFR
Report 1: Forest Lakes Appendices
Appendix A Photographs
Report 1: Forest Lakes Appendices
Figure 17-1: Pukehou “Hill of Dedication”
Report 1: Forest Lakes Appendices
Appendix B Traffic Data
y = 204.96x - 396838
1000
3000
5000
7000
9000
11000
13000
15000
17000
19000
1990 1995 2000 2005 2010 2015
An
nu
al A
ve
rag
e D
ail
y T
raff
ic (
vp
d)
Calendar Year
TRAFFIC GROWTH along SH 1N
OHAU - Telemetry Site
56 - Ohau Overbridge
Otaki, North Waitohu
Stream Bridge
Otaki, North of
Waerenga Rd
Linear (Otaki, North
Waitohu Stream
Bridge
)
-0.4%
1.2%
'01 to '11
'92 to '11
0.4%
1.3%
Report 1: Forest Lakes Appendices
Appendix C Crash Data
CRASH LIST DETAIL REPORTRun on: 4 Oct 2012
Crash List: Forest Lakes_July07 to June12 (20 crashes)Total Injury Crashes:Total Non-Injury Crashes:
Crash Type Number %Overtaking Crashes:Straight Road Lost Control/Head On:Bend - Lost Control/Head On:Rear End/Obstruction:Crossing/Turning:Pedestrian Crashes:Miscellaneous Crashes:
Environmental Factors Number %Light/Overcast Crashes:Dark/Twilight Crashes:
Wet/Ice:Dry:
Number %Day/PeriodWeekdayWeekend
Object Struck Number %
128
4185101
20
146
614
146
20
20
54025
505
100
100
7030
3070
100
7030
20
20
20 100
12 60
TOTAL:
TOTAL:
TOTAL:
TOTAL:
Crash factors (*) Number %
TOTAL:
Crash NumbersYear Fatal Non-Inj
TOTAL: 0 8
40 200
Sat - Sun
Intersection/Midblock6
Number %Intersection:MidBlock: 14TOTAL: 20
3070
100
20082009201020112012
Too fastFailed Giveway/StopOvertakingIncorrect Lane/posnPoor handlingPoor ObservationPoor judgementFatigueVehicle factorsRoad factorsWeatherOther
222385644121
1010101540253020205105
Note: Percentages represent the % of crashes in which the vehicle,cause or object appears.
Vehicles Number %CarVan/UteTruckBusMotorcycleBicycle
2372110
753010
550
TOTAL: 34 125
TOTAL:
Cliff BankDebrisOver BankFenceGuard RailTreeDitch
3221112
151010555
10
00000
31211
%
%
%
%
%
%
%
%
02111
14110
Serious Minor
5 7
Crashes with objects(s) struck 12 60%
Location Local road St.Highway TotalUrban 0 0 0Open road 0 20 20TOTAL: 0 20 20
% % %000
0100100
0100100 %
Crashes with a:Driver factor 32 160 %Environmental factor 3 15%(*) factors are counted once against a crash - ie two fatigued drivers count as one fatigue crash factor.Note: Driver/vehicle factors are not available for non-injury crashes for Northland, Auckland, Waikato and Bay of Plenty before 2007. This will influence numbers and percentages.
FOREST LAKES ROAD
LAWLORS ROAD
SH 1N
SH 1N
N
201012491
201052812
2852676
2911753
2812475
201112258
2911007
201113088
2854080
201251299
201011390
2911295
2856215
2952475
291179129122632912802
201050830
201211162
201152830
0.5 0 0.51Km 1.5Km
KEYFatalDarkWetIcyPedsCyclist
Forest Lakes
North of Taylors Road to Pukehou Rail Overbridge
Coded Crash report, run on 04-10-2012, Page 1First Street Second streetor landmark CrashNumber Date Day Time Factors and Roles TotalInj Map Coordinates
M DV RM VN VVVDD/MM/YYYY T 1 234DDD HHMMDistanceA is for vehicle 1B is for veh 2 etc F S MA E IT R N
|||||
||||||
||||||
||||||
||||||
||||||
||||||
||||||
DIR
OBJECT
CURVE
WETNES
LIGHT
WETHER
JUNCT
CONTRL
MARKS
SPDLMT
PEDage
CYCage
2852676 11/05/2008 Sun 0730 DA 4N1 132A 410A B L N C 100 54884661785598E W280S1N/995/0.262 PUKEHOU RLY OBR201052812 20/06/2010 Sun 1510 FF CS1VC 181A O H N L 100 54884601785501R W600S1N/995/0.359 ATKINS ROAD201152830 28/07/2011 Thu 1300 DA TS1 136A 631A V B F N C 100 54884571785421E D1200S1N/995/0.439 SOUTH MANAKAU ROAD201011390 01/03/2010 Mon 1300 DA MN1C 668A D B F N L 100 1 54883461784937E D310N1N/995/0.939 FOREST LAKES ROAD2952475 07/04/2009 Tue 1830 CB CS1 130A 402A C DN F T S L 100 54882011784687R D20N1N/995/1.229 FOREST LAKES ROAD2912263 26/06/2009 Fri 1755 GD 4S1C4B 331A 904 DO M T N L 100 1 54881891784670R WI1N/995/1.249 FOREST LAKES ROAD2911791 03/04/2009 Fri 1950 GD CS1VCC 331A 181C TO F T S L 100 2 1 54881891784670R DI1N/995/1.249 FOREST LAKES ROAD2911295 25/02/2009 Wed 0640 DC CE24 113A 321A 402A E O F T S C 100 1 54881891784670R DI1N/995/1.249 FOREST LAKES ROAD2856215 20/11/2008 Thu 0738 JA CN1C 301B B F T S L 100 54881891784670R DI1N/995/1.249 FOREST LAKES ROAD2912802 30/08/2009 Sun 1721 GD CS14C 331A 181C O H T N L 100 1 2 54881891784670R WI1N/995/1.249 FOREST LAKES ROAD201050830 05/03/2010 Fri 1600 GE VS1C 197A 193B B F T N L 100 54881891784670M DI1N/995/1.249 FOREST LAKES ROAD2854080 04/08/2008 Mon 0755 AD CN1VT 363A 372A 671A 902 T B F N L 100 54881551784621R W60S1N/995/1.309 FOREST LAKES ROAD201211162 28/01/2012 Sat 1230 QG 4S1 130A 661A 682A E B F N L 100 1 3 54880171784425R D300S1N/995/1.549 FOREST LAKES ROAD201251299 20/04/2012 Fri 1730 EC CS1 130A 341A D TN F N C 100 54879021784261E D500S1N/995/1.749 FOREST LAKES ROAD2911007 02/01/2009 Fri 0715 DB CN1 410A F O F N L 100 2 54878201784136E D650S1N/995/1.899 FOREST LAKES ROAD201113088 21/11/2011 Mon 1040 DB CN1 111A 131A 402A 800 V O L N C 100 1 54878101784118E W670S1N/995/1.919 FOREST LAKES ROAD201012491 11/07/2010 Sun 1730 AF VS1V 132A 155A 386A C DN F N L 100 1 54877161783852R D1100N1N/995/2.203 TAYLORS ROAD201112258 02/06/2011 Thu 0840 AD CS1C 130A 150A 407A C B F N L 100 1 1 54875941783534R D760N1N/995/2.543 TAYLORS ROAD2812475 14/05/2008 Wed 0840 BF CS14 400A 410A G B F N L 100 1 54874271783218E D400N1N/995/2.903 TAYLORS ROAD2911753 26/04/2009 Sun 0500 DB VS1 134A 410A DN F N C 100 1 54874121783204E D380N1N/995/2.923 TAYLORS ROAD
Report 1: Forest Lakes Appendices
Appendix D Outline Plans
Report 1: Forest Lakes Appendices
Appendix E Cost Estimates
Feasibility Estimate
Item Base Estimate Contingency Funding Risk
A 550,000 110,000 181,500
- Consultancy Fees 546,000 109,200 180,200
- NZTA Managed Costs 55,000 11,000 18,200
B 601,000 120,200 198,400
- Consultancy Fees 624,000 124,800 205,900
- NZTA Managed Costs 55,000 11,000 18,200
C 679,000 135,800 224,100
MSQA
- Consultancy Fees 630,000 126,000 207,900
- NZTA Managed Costs 45,000 9,000 14,850
- Consent Monitoring Fees 5,000 1,000 1,650
680,000 136,000 224,400
D1 Environmental Compliance 10,000 2,000 3,300
D2 Earthworks 818,400 245,500 409,200
D3 Ground Improvements 0 0 0
D4 Drainage 691,000 138,200 228,000
D5 Pavement and Surfacing 3,390,000 678,000 1,118,700
D6 Bridges 0 0 0
D7 Retaining Walls 0 0 0
D8 Traffic Services 1,466,750 293,400 484,000
D9 Service Relocations 1,485,000 297,000 490,100
D10 Landscaping 100,000 20,000 33,000
D11 Traffic Management and Temporary Works 600,000 120,000 198,000
D12 Preliminary and General 500,000 100,000 165,000
D13 Extraordinary Construction Costs 0 0 0
Sub Total Base Physical Works 9,061,150 1,894,100 3,129,300
D 9,741,150 2,030,100 3,353,700
E Project Base Estimate (A+B+C+D) 11,571,150
F (A+B+C+D) 2,396,100
G (E+F) 13,967,250
Project Property Cost Expected Estimate 660,000
Investigation and Reporting Expected Estimate 721,200
Design and Project Documentation Expected Estimate 814,800
Construction Expected Estimate 11,771,250
H (A+B+C+D) 3,957,700
I (G+H) 17,924,950
Project Property Cost 95th Percentile Estimate 841,500
Investigation and Reporting 95th Percentile Estimate 919,600
Design and Project Documentation 95th Percentile Estimate 1,038,900
Construction 95th Percentile Estimate 15,124,950
29 Jan 2013 Cost Index
Estimate prepared by: Graeme Corin Signed
Estimate internal peer review by: Signed
Estimate external peer review by: Signed
Estimate approved by NZTA Project Manager: Signed
Note: (1) These estimates are exclusive of escalation and GST.
Contingency (Assessed / Analysed)
Project Expected Estimate
Project Estimate - Form A
Project Name: Forest Lakes Improvements
Option 1
Physical Works
Nett Project Property Cost
Investigation and Reporting
FE
Base Date of Estimate
Total Design and Project Documentation
Total Construction & MSQA
Total Investigation and Reporting
Design and Project Documentation
Construction
Description
Sub Total Base MSQA
95th
Percentile Project Estimate
Funding Risk (Assessed / Analysed)
Issue 3 - Aug 2007 1/1 Printed 15/02/2013
Feasibility Estimate
Item Base Estimate Contingency Funding Risk
A 100,000 20,000 33,000
- Consultancy Fees 405,000 81,000 133,700
- NZTA Managed Costs 55,000 11,000 18,200
B 460,000 92,000 151,900
- Consultancy Fees 486,000 97,200 160,400
- NZTA Managed Costs 55,000 11,000 18,200
C 541,000 108,200 178,600
MSQA
- Consultancy Fees 485,800 97,160 160,300
- NZTA Managed Costs 45,000 9,000 14,850
- Consent Monitoring Fees 5,000 1,000 1,650
535,800 107,160 176,800
D1 Environmental Compliance 10,000 2,000 3,300
D2 Earthworks 688,400 206,500 344,200
D3 Ground Improvements 0 0 0
D4 Drainage 620,000 124,000 204,600
D5 Pavement and Surfacing 2,632,500 526,500 868,700
D6 Bridges 0 0 0
D7 Retaining Walls 0 0 0
D8 Traffic Services 1,466,750 293,400 484,000
D9 Service Relocations 1,485,000 297,000 490,100
D10 Landscaping 75,000 15,000 24,800
D11 Traffic Management and Temporary Works 360,000 72,000 118,800
D12 Preliminary and General 400,000 80,000 132,000
D13 Extraordinary Construction Costs 0 0 0
Sub Total Base Physical Works 7,737,650 1,616,400 2,670,500
D 8,273,450 1,723,560 2,847,300
E Project Base Estimate (A+B+C+D) 9,374,450
F (A+B+C+D) 1,943,760
G (E+F) 11,318,210
Project Property Cost Expected Estimate 120,000
Investigation and Reporting Expected Estimate 552,000
Design and Project Documentation Expected Estimate 649,200
Construction Expected Estimate 9,997,010
H (A+B+C+D) 3,210,800
I (G+H) 14,529,010
Project Property Cost 95th Percentile Estimate 153,000
Investigation and Reporting 95th Percentile Estimate 703,900
Design and Project Documentation 95th Percentile Estimate 827,800
Construction 95th Percentile Estimate 12,844,310
24 Sep 2012 Cost Index
Estimate prepared by: Graeme Corin Signed
Estimate internal peer review by: Signed
Estimate external peer review by: Signed
Estimate approved by NZTA Project Manager: Signed
Note: (1) These estimates are exclusive of escalation and GST.
FE
Base Date of Estimate
Total Design and Project Documentation
Total Construction & MSQA
Total Investigation and Reporting
Design and Project Documentation
Construction
Description
Sub Total Base MSQA
95th
Percentile Project Estimate
Funding Risk (Assessed / Analysed)
Contingency (Assessed / Analysed)
Project Expected Estimate
Project Estimate - Form A
Project Name: Forest Lakes Improvements
Option 2
Physical Works
Nett Project Property Cost
Investigation and Reporting
Issue 3 - Aug 2007 1/1 Printed 15/02/2013
Report 1: Forest Lakes Appendices
Appendix F Economic Analysis Worksheets
Simplified Procedure 3 - General Road Improvements
GENERAL ROADING IMPROVEMENT WORKS:EVALUATION SUMMARY WORKSHEET 1
1 Evaluator(s) Dhimantha RanatungaReviewer(s) David Wanty
2 Project / Package Details
Approved Organisation NameProject / Package NameYour ReferenceProject DescriptionDescribe the problem to be addressed
3 Location
Brief description of location
4 Alternatives and Options
Describe the Do Minimum
Summarise the options assessed
5 TimingTime Zero (assumed construction start date)Expected duration of construction (Months)
6 Economic EfficiencyDate economic evaluation completed (mm/yyyy)Base date for costsAADT at Time ZeroTraffic Growth Rate at Time Zero (%)
Existing Roughness IRI or NAASRA Existing Traffic Speed km/hrPredicted Roughness IRI or NAASRA Predicted Traffic Speed km/hrLength of Job Before Improvements km Posted Speed Limit km/hrLength of Job After Improvements km Road TypeLength of new highway km Gradient Before Improvements
Length of existing highway used km Gradient After Improvements
7 A
8 B
9 Benefit values from Worksheet 4, 5 or 6
PV Travel Time Cost savings: $ C x Update FactorTT
= $ W
PV VOC & CO2 savings: x Update FactorVOC
PV Accident Cost savings: x Update FactorAC
10 =
11
2.70 1002.80
3%2.802.80
2.80
1 -
B/C Ratio =
$
BENEFITS
$0
Z
Y= $ NIL
$17,428,200
1.04D
15124778 - 0FYRR = 1
st Year BENEFITS
COSTS==
PV Cost of Do Minimum Cost $ $0
$0 1.33 NIL
PV Cost of the preferred Option Cost $ $15,124,778
(est)
Rural Strategic3%
100
100
1 -
0.10[(0+0)/12.21+17428200/11.08] x 0.9259
1.2
= $E
=COSTSB - A
W + Y + Z 0 + 0 + 17428200
$ $14,895,897
15124778 - 0
1.17
=
1 July 20136
Option 1: Install TL4 WRB, widen existing carriageway to 16 m (4 m median, two 3.5 m
lanes and 2.5 m shoulders) between Taylors Rd and Pukehou Rail Overbridge and a
single curve realignment from 425 m radius to 1100 m.
NZTAOtaki to Levin: Forest Lakes PFRZ1925700Safety ImprovementsReduce crashes
Do nothing
State Highway 1, north of Otaki, between Taylors Road (north) and Pukehou Rail Overbridge
1/995/0.25 to 1/995/3.05
2.70
26 September 20121 July 2012
157001.3%
File Alt_Option 1_SP3_DKWver1e.xlsx, Worksheet WS 1
9/10/2012 9:55 a.m. Page 1 of 1
Simplified Procedure 3 - General Road Improvements
GENERAL ROADING IMPROVEMENT WORKS:EVALUATION SUMMARY WORKSHEET 1
1 Evaluator(s) Dhimantha RanatungaReviewer(s) David Wanty
2 Project / Package Details
Approved Organisation NameProject / Package NameYour ReferenceProject DescriptionDescribe the problem to be addressed
3 Location
Brief description of location
4 Alternatives and Options
Describe the Do Minimum
Summarise the options assessed
5 TimingTime Zero (assumed construction start date)Expected duration of construction (Months)
6 Economic EfficiencyDate economic evaluation completed (mm/yyyy)Base date for costsAADT at Time ZeroTraffic Growth Rate at Time Zero (%)
Existing Roughness IRI or NAASRA Existing Traffic Speed km/hrPredicted Roughness IRI or NAASRA Predicted Traffic Speed km/hrLength of Job Before Improvements km Posted Speed Limit km/hrLength of Job After Improvements km Road TypeLength of new highway km Gradient Before Improvements
Length of existing highway used km Gradient After Improvements
7 A
8 B
9 Benefit values from Worksheet 4, 5 or 6
PV Travel Time Cost savings: $ C x Update FactorTT
= $ W
PV VOC & CO2 savings: x Update FactorVOC
PV Accident Cost savings: x Update FactorAC
10 =
11
2.70
26 September 20121 July 2012
157001.3%
1 July 20136
Option 2: Install TL4 WRB, widen existing carriageway to 13.5 m (1.5 m median, two 3.5
m lanes and 2.5 m shoulders) between Taylors Rd and Pukehou Rail Overbridge and a
single curve realignment from 425 m radius to 550 m.
NZTAOtaki to Levin: Forest Lakes PFRZ1925700Safety ImprovementsReduce crashes
Do nothing
State Highway 1, north of Otaki, between Taylors Road (north) and Pukehou Rail Overbridge
1/995/0.25 to 1/995/3.05
B - AW + Y + Z 0 + 0 + 16811850
$ $14,369,102
12416731 - 0
1.17
=
0.11[(0+0)/12.21+16811850/11.08] x 0.9259
1.4
= $E
=COSTS
(est)
Rural Strategic3%
100
100
1 -
PV Cost of Do Minimum Cost $ $0
$0 1.33 NIL
PV Cost of the preferred Option Cost $ $12,416,731
12416731 - 0FYRR = 1
st Year BENEFITS
COSTS==
B/C Ratio =
$
BENEFITS
$0
Z
Y= $ NIL
$16,811,850
1.04D
2.70 1002.80
3%2.802.80
2.80
1 -
File Alt_Option 2_SP3_DKWver1e.xlsx, Worksheet WS 1
9/10/2012 9:46 a.m. Page 1 of 1
Simplified Procedure 3 - General Road Improvements
BCR AND INCREMENTAL ANALYSIS WORKSHEET 7
Time Zero 1/07/2013 Base Date 1/07/2012
BCRN Do Minimum Option: 1 Option: 2 Option: 3 Option: 1 Option: 2 Option: 3
Travel Time Cost Savings $0 $0
VOC & CO2 Savings $0 $0
Accident Cost Savings $17,428,200 $16,811,850
PV Total Net Benefits $17,428,200 $16,811,850
PV of Costs as Calculated
Capital Costs $0 $13,996,900 $11,360,735 $13,996,900 $11,360,735
Maintenance Costs $0 $1,157,878 $1,055,996 $1,157,878 $1,055,996
PV Total Net Costs $0 $15,154,778 $12,416,731
1.2 1.4
Preferred Option
BCR
Then Incremental
BCR
Option Total Costs Total Benefits Option Total Costs Total
Benefits
Incremental
Costs
Incremental
Benefits
Incremental
BCRN
B/C <= 2 1.0
(1) (2) (3) (4) (5) = (3) - (1) (6) = (4) - (2) (7) = (6) / (5) 2 < B/C < 4 2.0
Option: 2 $12,416,731 $16,811,850 Option: 1 $15,154,778 $17,428,200 $2,738,047 $616,350 0.2 B/C >= 4 4.0
Preferred Option =Option: 2
PV of Benefits as Calculated PV of Net Benefits
PV of Net Costs
BCRN
BASE OPTION FOR COMPARISON NEXT HIGHER COST OPTION INCREMENTAL ANALYSIS
File WS7_incremental BCR.xlsx, Worksheet TBC_WS 7
9/10/2012 9:45 a.m. Page 1 of 1