Winstone Aggregates. Three Kings Quarry Filling, Mt Eden Road, Auckland TRANSPORTATION ASSESSMENT REPORT. June 2008

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1 Winstone Aggregates Three Kings Quarry Filling, Mt Eden Road, Auckland TRANSPORTATION ASSESSMENT REPORT PO Box 2592 Auckland Phone : New Zealand June

2 Winstone Aggregates Three Kings Quarry Filling, Mt Eden Road, Auckland TRANSPORTATION ASSESSMENT QUALITY ASSURANCE STATEMENT Prepared by: Max Robitzsch Transportation Engineer Reviewed by: Daryl Hughes Principal Transportation Engineer Approved for Issue by: Daryl Hughes Principal Transportation Engineer Status: Final Report Date: 12 June 2008

3 TABLE OF CONTENTS 1. INTRODUCTION SITE DESCRIPTION Background Surrounding Areas EXISTING TRAFFIC CONDITIONS Road Network Traffic Flows Road Safety Landscape Road Intersection Quarry Access Intersection Kingsway Intersection Grahame Breed Drive Intersection Mt Albert Road Intersection Other Intersections & Mid-Block Road Safety Summary PROPOSED ACTIVITY AND TRIP GENERATION Existing Quarry Traffic Future Operations Projected Total Site Traffic ROAD NETWORK CHANGES Traffic Growth Committed Roading Schemes Section Summary TRIP DISTRIBUTION Quarry Traffic Trip Distribution North Distribution Scenario South Distribution Scenario Section Summary CAPACITY MODELLING Background Performance Indicators Peak Hours Gap Acceptance Scenarios Modelled Intersection Modelling Mount Eden Road / Landscape Road Mt Eden Road / Site Access...17

4 7.3.3 Kingsway Grahame Breed Drive Mt Eden Road / Mount Albert Road / Warren Avenue Section Summary SECOND ACCESS Background Two-Way Scenario Site Access Second Access One-Way Scenario Site Access Second Access Section Summary CONCLUSIONS...27

5 1 WINSTONE AGGREGATES Three Kings Quarry Filling, Mt Eden Road, Auckland Transportation Assessment Report 1. INTRODUCTION Traffic Design Group has been commissioned by Winstone Aggregates ( Winstone ) to provide a transportation assessment of their future filling operations at their quarry site at Mt Eden Road, Three Kings in Auckland. The key traffic planning issues arising from this assessment are: the additional traffic generated by the proposed filling operations, in conjunction with continuing quarry work, and the integration of this traffic into the surrounding road network; the effect that the additional traffic would have on the operational safety and efficiency of the surrounding road network, specifically the major intersections along Mt Eden Road between Landscape Road and Mt Albert Road; the ability of the existing site access to accommodate the expected traffic increases; compliance with the Auckland City District Plan - Isthmus Section ( District Plan ) and the relevant New Zealand Standards; and the viability of a secondary quarry access between Kingsway and Grahame Breed Drive. These and other matters will be addressed in detail in the following report. By way of summary however, it is established that the additional traffic can be accommodated in such a way that the effects on the function, capacity and safety of the surrounding road network will be unproblematic. A second access was also found to be feasible, but did not double the effectiveness of a single access. 2. SITE DESCRIPTION 2.1 Background The Winstone Three Kings Quarry is an operating scoria quarry, contained within land purchased by the Winstone family in Quarrying has occurred at this location for over 150 years. The Winstone land area is ha, with areas of about half this size to the immediate north and south having previously been quarried by, or for, others. The site contains a network of haulage roads, quarry plant areas, and has an area of about 1 ha sublet for commercial use (retail, manufacturing and warehousing). The sublet commercial area sits south of the single site access (onto Mt Eden Road) which is located at the site s north-east corner. This commercial area is zoned Business 7 (Quarry) in the District Plan and would be available to be quarried in the future, while the plant positions will be shifted within the site as the process of quarrying, and any filling, changes the site layout.

6 2 Additional quarry zoned and previously quarried reserve land to the south and west of the site, administered by Auckland City Council ( Council ), is considered unlikely to be further quarried. 2.2 Surrounding Areas The quarry is zoned Business 7 in the District Plan with the accompanying classification Management and Extraction of Mineral Resources, and is bounded by: Mt Eden Road and residential areas (mostly Residential 6a) to the east; Grahame Breed Drive and Three Kings Park (Public Open Space 3) to the south beyond the reserve land zoned Business 7 and administered by Council; Quarry reserve land (Business 7, unlikely to be further quarried) to the southwest; Big King Reserve (Public Open Space 1) and residential areas (Residential 6a) to the west; and mixed residential / retail-commercial areas (Business 4) off Hunters Park Drive to the north. Figure 1 is an aerial view of the site taken in 2007 and shows the broad relationship between the site and the surrounding features. 3. EXISTING TRAFFIC CONDITIONS 3.1 Road Network Figure 2 shows the road hierarchy of the surrounding streets as set out in the transport provisions of the District Plan. The site lies on the western edge of Mt Eden Road, which connects with Mt Albert Road approximately 600m south of the site entrance. Mt Eden Road is classified as a District Arterial Road. It has one traffic lane in each direction of travel and a sealed width of approximately 10.5m in the vicinity of the quarry entrance. A flush median of approximately 2.75m width separates the two directions of travel. On-street parking is allowed along most of the site frontage. Mt Albert Road lies to the south of the site and is classified as a Regional Arterial. It has one traffic lane in each direction of travel, and a sealed width of approximately 14m in the section west of the Mt Eden Road intersection. The traffic lanes are separated by a flush median of approximately 2.75m width. East of the intersection, the road narrows down to a sealed width of approximately 11m, with two lanes in each direction of travel and no median. Landscape Road is situated to the north of the site and is defined as a Local Road east of its intersection with Mt Eden Road, and as a Collector Road west of it. Both sections have one traffic lane in each direction of travel. Grahame Breed Drive and Kingsway Road are both Local Roads in the vicinity of the site. Each provides one traffic lane in each direction. The intersection of Mt Eden Road and Mt Albert Road is signal-controlled, and all other intersections discussed in this report are priority-controlled (Stop, or Give-Way).

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9 5 3.2 Traffic Flows Five intersections, including the site access, were surveyed as part of this assessment during November 2006 as follows: Thursday, 16 November :00am to 9:00am - 3:00pm to 6:00pm Saturday, 18 November :00am to 2:00pm The following intersections along Mt Eden Road were surveyed: Landscape Road; Quarry site access; Kingsway; Grahame Breed Drive; and Mt Albert Road. The peak hours of the surveyed intersections were found to be 7:30am to 8:30am and 4:00pm to 5:00pm on a weekday and 11:45am to 12:45pm on a Saturday. The surveyed volumes for these hours are given in Figures 3 to Road Safety An analysis of the road safety record of the area in the immediate vicinity of the site was undertaken using the Land Transport New Zealand Crash Analysis System for the period from 2001 to The search spanned the entire length of Mt Eden Road from Landscape Road to Mt Albert Road, including each of the intersections. Crashes in this timeframe and area are discussed below Landscape Road Intersection This intersection reported 14 crashes. The main factors were crossing / turning (79% of all crashes) and rear end / obstruction (21% of all crashes). Four of the crashes caused injuries, resulting in five minor and one serious injury. The latter arose as a result of a car driver being inattentive and not stopping as required while crossing the intersection. One non-injury crash involved a truck crossing Mt Eden Road and failing to give way to a car Quarry Access Intersection One non-injury incident was reported at the quarry entrance, involving a car and a truck simultaneously turning left out of the intersection Kingsway Intersection At this intersection there were three reported non-injury crashes; all involving rear end collisions.

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15 Grahame Breed Drive Intersection Three crashes, including one minor injury and two non-injury events occurred at this intersection. All three involved rear end collisions / obstruction types of vehicle manoeuvres Mt Albert Road Intersection There were a total of 41 reported crashes at this intersection over the five year period. The main contributing factors were crossing / turning (41% of all crashes), rear end / obstruction (29%), and overtaking (17%). Pedestrians were involved in 5% of the events. Otherwise, crashes reported showed no specific pattern, as actual locations and specific causes varied. The crashes involved injuries in nine events, involving a variety of factors and resulting in seven minor injuries and two serious injuries. The serious injuries arose from manoeuvres involving a car cutting a corner and hitting a cyclist, and a driver suffering a heart attack. One crash involved a car failing to give way to an oncoming truck, and resulted in a minor injury Other Intersections & Mid-Block These sections of the investigated area revealed a total of 33 reported crashes, including nine which resulted in injuries. The main contributing factors were rear end / obstruction (39% of all crashes) and losing control (33%) as well as crossing / turning (15%). Otherwise, crashes reported showed no specific pattern, as actual locations and specific causes varied. One non-injury crash involved a truck travelling southbound on Mt Eden Road being hit by a car leaving a residential access. Another non-injury crash involved a manoeuvring truck hitting a parked car Road Safety Summary In total, 95 crashes were reported in this area of Mt Eden Road over the five year period The local ratio of serious injuries to minor injuries was one serious to 7.3 minor injuries, which is broadly similar to the average rate for Auckland City at one serious to 6.4 minor injuries. Five crashes out of this total of 95 reported events involved trucks, representing 5.3% of all accidents. In the whole of Auckland, events involving trucks during the same timeframe made up approximately 9% of all accidents. While the sample size of the statistical event (crash) is still relatively small, this indicates that trucks are less likely to be involved in accidents in the surrounding network than in the whole of the Auckland region. The above data establishes that the study area is operating relatively safely. Based on injury rates being comparable to Auckland in general, the lack of clustering of specific accident types or locations, and the low rate of truck-related accidents, there is no indication that an increase in traffic would affect the safety of the local road network. Certainly there is no identifiable road safety deficiency that would suggest any difficulty for the road network to accommodate an increase in truck traffic movements. 4. PROPOSED ACTIVITY AND TRIP GENERATION 4.1 Existing Quarry Traffic The Winstone quarry at Three Kings would be able to remain in active operation up to at least the year 2030, as it holds Auckland Regional Council resource consent to dewater (and consequently extract)

16 12 down to RL 0m, ie: approximately 34m below the present pit floor. It currently produces about 150,000 to 200,000 m 3 of loose rock per year, which, depending on the product, converts to mass at between 1 and 1.4 tonnes per m 3. The current consents for quarry operation do not limit the extraction to any specific total, although the maximum hourly rate of extraction and processing is a condition of the air permit. Trucks and general vehicle movements are not restricted by consent or District Plan rule to a specific maximum number. Based on Winstone quarry data provided to TDG, the annual daily average of heavy commercial vehicle (HCV) movements is approximately 70 (counting both inbound and outbound movements). During short term peak times of the year, daily averages can double up to approximately 140 HCV movements / day. To ensure a robust analysis, the assessment procedures in this report have adopted this double volume of base site traffic for all analyses. 4.2 Future Operations Provided the necessary resource consents are obtained, Winstone expects filling of the quarry to start by 2010, and then take approximately eight to 10 years to complete. However, factors such as the level of general economic activity and the availability of other fill sites over time make exact calculation of this duration difficult. Backfilling means quarrying at Three Kings will cease at some point in the future during the fill operation, and Winstone is proposing that the site serve as a reshipment yard for aggregate material from other sites until redevelopment is complete. The timescales of these changes will see an ongoing fluctuation of quarry / reshipment traffic throughout the study period. 4.3 Projected Total Site Traffic As mentioned above, the frequency of truck movements varies throughout the year, according to customer demand, and fluctuates above or below the average daily frequency. It was considered important to ensure that the potential worst-case scenario was analysed in this report, therefore the analysis has been based on the consideration that during peak times of the year, the maximum daily truck movements would be double the average. Combining all three traffic types - quarrying traffic, fill traffic and expected reshipment traffic - Winstone have estimated that the annual heavy vehicle use at the site could reach an average of 373 truck movements per day, which doubled to simulate peak times of year equates to a maximum of 745 daily heavy vehicle movements. However, when fill operations commence, Winstone has advised that it expects to initially deploy fill material to create roads and earth structures to allow quarrying and fill activity to be carried out independently. This will see fill operations being less than the predicted average or peak estimates, with vehicle numbers ramping up over time. Based on surveyed traffic flow data collected throughout Auckland as well as on histograms of daily distribution at other quarry sites, it is considered that the site generates 7.5% of its daily traffic generation during each of the network peak hours. This represents a somewhat conservative assumption, with peak hour site traffic at other Winstone quarry sites reported to be as low as 5% of the daily site total.

17 13 5. ROAD NETWORK CHANGES 5.1 Traffic Growth As the timeframe of the project is relatively long-term, it is important to not only project the trip generation of the site, but also make some assessment of projected local traffic growth beyond the surveyed levels. Land Transport New Zealand s Project Evaluation Manual (September 2006) states that on urban arterial roads in Auckland City, the expected traffic growth rate is 1.5% per annum. To validate this standard rate, data from Auckland City week-long detector counts south of the site was analysed. These established that there was a 3% per annum reduction in traffic on Mt Eden Road between 2004 and Other detector counts further north on Mt Eden Road showed the same reduction trends during those years, even taking into account the seasonal variation between some of the surveyed weeks. With this recent measured annual reduction of traffic on Mt Eden Road, it is considered appropriately conservative to adopt the 1.5% future growth rate, as provided within the Project Evaluation Manual. 5.2 Committed Roading Schemes As shown in Figure 2, SH20 runs within 2 km of the site. Work is currently being undertaken to upgrade and extend SH20 between Hillsborough Road and Richardson Road, and this is projected to have a significant impact on the surrounding road network. The Transit New Zealand document SH20 Hillsborough Road to Richardson Road is a scheme assessment report upon which the viability of the scheme was established. It provides details of projected changes in traffic volumes upon scheme completion in The report concludes that a reduction of daily volumes of approximately 12.5% on Mt Eden Road, reductions of some 35% on Mt Albert Road west of Mt Eden Road, and reductions of 22% on Mt Albert Road to the east of the intersection will occur on scheme completion. The findings of this report resulted from an extensive network modelling exercise using Transit New Zealand project evaluation techniques, which was subsequently peer reviewed by Council. The results were then subject of Auckland City Council hearings and the Environment Court process. It is therefore considered that this data provides a strong basis from which to project the effects of the SH20 works. 5.3 Section Summary This study uses an annual growth rate of 1.5% per annum on the study network, and also applies onetime percentage reductions (of 12.5% to 35%) to the traffic volumes of Mt Eden Road and Mt Albert Road to reflect projected network effects from the opening of the SH20 extension scheme in 2009.

18 14 6. TRIP DISTRIBUTION 6.1 Quarry Traffic Trip Distribution Quarry activity and hence the distribution of site traffic is market driven and can fluctuate depending on the location of demand and supply. For this reason, this report looks at two worst-case scenarios, described below. All scenarios also include two cars per hour for every turning movement into and out of the site, to account for the light level of such traffic as found during the surveys. This does not change in any scenario, as Winstone Aggregates has no reason to expect that car traffic into or out of the site would alter substantially. 6.2 North Distribution Scenario In this scenario, the distribution of trucks into and out of the site would be 70% directed to and from the north and 30% to and from the south. The site-generated traffic would primarily travel to / from sites to the north, ie: Auckland CBD, North Shore or north of the region. Quarry traffic would be expected to travel Northbound along Mt Eden Road and straight through the Landscape Road / Mt Eden Road intersection. The signalised Balmoral Road / Mt Eden Road intersection would allow trucks to then disperse in various directions, reducing the effects on the general area from this point. 6.3 South Distribution Scenario In this scenario, the distribution of trucks into and out of the site would be 30% directed to and from the north and 70% to and from the south. In this scenario, most trucks are expected to turn right onto Mt Eden Road and then left at the Mt Albert Road intersection to reach SH20 via the new Hillsborough Road interchange. Some small volumes of site traffic would also turn right onto Mt Albert Road or go straight onto Warren Avenue / Hayr Road southwards. Distribution of the additional site traffic at this intersection is therefore expected be 70% to and from Mt Albert Road east, 20% to and from Warren Avenue / Hayr Road and 10% to and from Mt Albert Road west. 6.4 Section Summary The analysis uses two scenarios in which the site-specific traffic would predominantly use roads either north or south of the site, heading to / from the Balmoral Road / Mt Eden Road intersection or the SH20 Hillsborough interchange respectively. These strongly directionally biased scenarios are unlikely to persist for more than short periods of time (months at most), with distribution normally expected to be more even in terms of north-south split. Major projects close by that may affect vehicle directionality (such as the potential use of the quarry as a fill site for spoils from a Waterview Connection tunnel), may require additional analysis to assess their impact however, the above scenarios allow a conservative and appropriate analysis of peak demands on the road network to be undertaken, with the consideration that traffic flows for much of the time will be far less than these peak conditions.

19 15 7. CAPACITY MODELLING 7.1 Background Capacity modelling was undertaken using the widely adopted SIDRA Intersection V3.2 design and assessment software Performance Indicators As a site-specific program, SIDRA Intersection analyses expected capacities and vehicle delays, giving an indication of expected intersection performance. It calculates a number of performance indicators, the main indicators presented within this report being: Degree of Saturation (vehicles/capacity), which gives a percentage of theoretical capacity utilised in accommodating the traffic flows being considered; Average delay (seconds/vehicle), defining the delay to the typical motorist; and Level of Service (), based on the above delay to motorists, graded from A (no or minimal delays) to F (extreme delays) Peak Hours The traffic surveys established that the highest volumes lie within the weekday morning and late afternoon peaks. It is therefore considered that as the weekday peak hour volumes are somewhat greater (and occur in the same tidal directions) a separate Saturday model is not required Gap Acceptance Gap acceptance is a term used to model the behaviour of drivers at priority controlled intersections. The gap is the average length of delay in seconds between two vehicles in the traffic flow having priority that must exist before a waiting driver not having priority will accept the gap and enter or cross the flow. This delay is strongly variable for both individual drivers and local situations, depending on criteria like the acceleration capabilities of the vehicle, the local road speeds and sight distances involved, as well as on how hurried (and therefore willing to take increased risks) the driver is. For the first waiting vehicle, the minimum gap is larger than the additional gap needed for subsequent vehicles directly following the first into the same gap. The capacity models in this report use the default values of SIDRA unless otherwise specified. 7.2 Scenarios Modelled SIDRA models were set up to analyse the weekday morning and late afternoon peak hour intersection performances for the current and predicted future site traffic. The following scenarios were modelled: C1 F1 F 2 Current traffic (2006) uses site traffic (140 HCV / day) and general road traffic Future, without fill traffic (2014) - uses 2006 site traffic (140 HCV / day) but projected 2014 general road traffic Future, with fill traffic (2014) - assumes added fill traffic on top of 2006 site traffic (745 HCV / day total) and uses projected 2014 general road traffic

20 Intersection Modelling Except where specified in the description, all intersection approaches were modelled as having a single lane in each direction. The performance indicators of all applicable movements (left turn, through movement, right turn) of any single approach direction were summarised into one figure for each arm. Only at the quarry site access are all movements given individually Mount Eden Road / Landscape Road The Landscape Road / Mt Eden Road intersection was modelled as a Give Way intersection, with Landscape Road as the minor road. On Mt Eden Road, central right turn lanes of 30m (southbound) and 35m (northbound) were modelled. On both Landscape Road approaches, it was considered that the approach lanes were wide enough to function with a separate, short left-turn lane. As this intersection lies to the north of the site, the North distribution scenario was utilised to test the upper estimate of the site traffic on the intersection. The results from this scenario analysis are summarised in Tables 1 and 2 below: Approach Current Base Situation (C1) - AM Current Base Situation (C1) - PM Mt Eden Rd Northbound (N/B) A A Landscape Rd Westbound (W/B) C C Mt Eden Rd Southbound (S/B) A A Landscape Rd Eastbound (E/B) C C Table 1 : Mt Eden Road / Landscape Road intersection, Current = Degree of Saturation (Vehicles / Capacity), = Delays (seconds), = Level Of Service Table 1 demonstrates that this intersection currently performs well during AM and PM peak periods, with some minor delays on the Landscape Road approaches. A performance to C is generally acceptable for side-road approaches connecting with District Arterials such as Mt Eden Road. Approach Future Base Situation (F1) - AM Future Predicted Situation (F2) - AM Future Base Situation (F1) - PM Future Predicted Situation (F2) - PM Mt Eden Rd N/B A A A A Landscape Rd W/B C C C C Mt Eden Rd S/B A A A A Landscape Rd E/B C C B C Table 2 : Mt Eden Road / Landscape Road Intersection, Future The future base situation F 1 still operates within normal operating parameters, and the addition of the future predicted site traffic in F2 sees only a minor increase in parameters. This slight increase does not cause any problems with the intersection performance.

21 17 The above results establish that the Landscape Road intersection would not experience any substantial changes due to the future fill activity Mt Eden Road / Site Access The Mt Eden Road / Site Access intersection was modelled as a Give Way T-intersection, with the site access road operating as the minor road. On Mt Eden Road, the median was modelled as providing a southbound right turn lane of 50m. The site access was modelled as providing a left-turn lane and a right-turn lane for outbound traffic. For left turns out of a minor road, the SIDRA default gap acceptance values are 5.0 seconds for the initial movement and 3.0 seconds for the follow-up gap, and for right turners, 7.0 seconds and 4.0 seconds respectively. For the movements out of the site, values of 4.0 seconds for the initial and 3.0 seconds for the follow-up gap were used. This represents the greater likelihood of truck drivers accepting shorter length gaps in Mt Eden Road traffic flows. Experience has shown that this modelling practice better approximates the real situation at a heavy vehicle site access, with vehicles having priority being slightly more likely to slow down and allow trucks to enter the traffic flow. It also ties in with observations made on-site. Both the North and South distribution scenarios were modelled to test the sensitivity of the site access intersection during all possible eventualities. The results from this scenario analysis are summarised in Tables 3 to 6: Movement C1 AM, North Scenario C1 PM, North Scenario Mt Eden Rd N/B, left A A Mt Eden Rd N/B, thru A A Mt Eden Rd S/B, thru A A Mt Eden Rd S/B, right E E Site Access E/B, left D D Site Access E/B, right F F Table 3 : Mt Eden Road / Site Access intersection, Current North Distribution Scenario The above results demonstrate that the site access intersection functions relatively well at current traffic levels and with a predominantly northern site traffic flow. Delays are at an acceptable level for an industrial site and are only experienced by site traffic.

22 18 Movement C1 AM, South Scenario C1 PM, South Scenario Mt Eden Rd N/B, left A A Mt Eden Rd N/B, thru A A Mt Eden Rd S/B, thru A A Mt Eden Rd S/B, right D E Site Access E/B, left C C Site Access E/B, right F F Table 4 : Mt Eden Road / Site Access intersection, Current South Distribution Scenario The above results demonstrate that in comparison to the North distribution scenario, the site traffic experiences stronger delays when heavy vehicles wish to turn right out of the site towards Mt Albert Road. This is because a higher proportion of truck drivers in the South Scenario must give way to both directions of traffic on of Mt Eden Road. The delays are still at an acceptable level for site traffic leaving an industrial site, and do not affect Mt Eden Road. F1 - AM F2 - AM F1 - PM F2 - PM Movement Mt Eden Rd N/B, left A A A A Mt Eden Rd N/B, thru A A A A Mt Eden Rd S/B, thru A A A A Mt Eden Rd S/B, right E F E F Site Access E/B, left D E D E Site Access E/B, right F F F F Table 5 : Mt Eden Road / Site Access intersection, Future North Distribution Scenarios In the future for the north distribution scenario F1, the intersection continues to perform adequately during each of the peak hours. Adding the projected site traffic using the North distribution scenario F2, the intersection sees increases in delays to site traffic projected turning right out of the site, with delays of up to three minutes.

23 19 F1 - AM F2 - AM F1 - PM F2 - PM Movement Mt Eden Rd N/B, left A A A A Mt Eden Rd N/B, thru A A A A Mt Eden Rd S/B, thru A A A A Mt Eden Rd S/B, right D F D F Site Access E/B, left C D C D Site Access E/B, right F F F F Table 6 : Mt Eden Road / Site Access intersection, Future South Distribution Scenarios Using the south distribution scenario F2 sees the performance of the intersection decline for the right turn out of the site, with all other movements remaining at normal levels. Vehicles within the site intending to turn right are delayed for around seven minutes during the afternoon peak. Such long delays could be avoided by rescheduling movements to off-peak times or by diverting some trucks onto other routes turning out northwards first. The above analysis establishes that the site intersection would experience peak hour delays to right turning vehicles into the site and especially to right turning vehicles out of the site. All other movements during all other scenarios are likely to continue to operate normally. It is considered that the projected delays would not be experienced to this degree in practice, as drivers would alter their routing to account for the network situation. This would see more trucks turning left and then rerouting to the south using other routes, such as via Khyber Pass, Greenlane or State Highway 1, which can be accessed to the north of the site. The North distribution scenario results have demonstrated that this shift in patterns and an increase in left turns can be accommodated Kingsway The Kingsway / Mt Eden Road intersection was modelled as a give-way intersection, with Kingsway as the minor road. On Mt Eden Road approach, a northbound median right turn lane of 50m was modelled, while Kingsway is wide enough to function as if two lanes would operate at the Give Way line. As the intersection lies to the south of the site entrance, the South distribution scenario was utilised to test the impact of the site traffic on the intersection. The results from this scenario analysis are summarised in Tables 7 and 8: Approach C1 - AM C1 - PM Mt Eden Rd N/B A A Kingsway W/B C C Mt Eden Rd S/B A A Table 7 : Mt Eden Road / Kingsway Intersection, Current

24 20 The above table establishes that the intersection currently functions well during the morning and late afternoon peak hours. F1 - AM F2 - AM F1 - PM F2 - PM Approach Mt Eden Rd N/B A A A A Kingsway W/B C C C C Mt Eden Rd S/B A A A A Table 8 : Mt Eden Road / Kingsway intersection, Future This shows that in the future, the intersection would continue to perform well for both F 1 and F 2 scenarios. The above results indicate that the Kingsway intersection would not experience any substantial degradation of performance due to future fill activity at the estimated peak site traffic levels Grahame Breed Drive The Grahame Breed / Mt Eden Road intersection was modelled as a Give Way intersection, with Grahame Breed as the minor road. On the Mt Eden Road southbound median, a 50m right turn lane was modelled. As the intersection lies to the south of the site entrance, the South distribution scenario was utilised to test the impact of the site traffic on the intersection. The results from this scenario analysis are summarised in Tables 9 and 10: Approach C1 - AM C1 - PM Mt Eden Rd N/B A A Mt Eden Rd S/B A A Grahame Breed Drive E/B B B Table 9 : Mt Eden Road / Grahame Breed Drive intersection, Current F1 - AM F2 - AM F1 - PM F2 - PM Approach Mt Eden Rd N/B A A A A Mt Eden Rd S/B A A A A Grahame Breed Drive E/B B B B B Table 10 : Mt Eden Road / Grahame Breed Drive intersection, Future

25 21 The results establish that this intersection would continue to perform well during each of the peak hours, distribution scenarios and future years. Changes to the performance of the intersection due to the addition of future site traffic are negligible. It is considered therefore that the Grahame Breed intersection would not experience any significant changes in its peak hour operational performance due to the future fill activity Mt Eden Road / Mount Albert Road / Warren Avenue The Mt Eden Road / Mt Albert Road intersection was modelled as a signalised intersection, with the traffic signal phasing arrangements used for the intersection taken from SCATS data. Phasing durations were calculated by SIDRA to allow scenarios to be compared, in much the same way as the on-theground signal controllers adjust phasing times in response to changing traffic flows. For this intersection, queue lengths were also studied to improve calibration of the model with the 2006 surveys. In the absence of surveyed pedestrian numbers, these were modelled to be 50 people per hour crossing each approach of the intersection. The approach lanes and their approximate lengths are shown in Figure 8 below: Figure 8 : Mt Albert Road / Mt Eden Road intersection with short lane lengths (m) As the intersection lies to the south of the site, the South distribution scenario was utilised to test the impact of the site traffic on the intersection. The results from this scenario analysis are summarised in Tables 11 to 12:

26 22 Approach Summary C1 AM C1 PM Warren Avenue N/B C C Mt Albert Road W/B C B Mt Eden Rd S/B C D Mt Albert Road E/B B B Table 11 : Mt Eden Road / Mt Albert Road intersection, Current The above results show that this intersection currently functions reasonably well, with delays to Northbound and Southbound traffic reaching over 30 seconds / vehicle during the PM peak. Approach Summary F1 AM South F2 AM South F1 PM South F2 PM South Warren Avenue N/B B B C C Mt Albert Road W/B B C B B Mt Eden Rd S/B B B C C Mt Albert Road E/B B B B B Table 12 : Mt Eden Road / Mt Albert Road intersection, Future As shown in the results, the performance of the intersection is expected to improve for both future scenarios, as some traffic has been diverted from the intersection due to the completion of SH20. The intersection s performance has generally improved, and the change that the additional site traffic causes on the intersection is negligible. 7.4 Section Summary The above analyses demonstrate that site traffic would experience some delays when using the site intersection during the future peak hours. However, these delays are limited exclusively to site vehicles, with queuing being held either entirely within the site or within the existing right-turn flush median on Mount Eden Road. The wider highway network would therefore see negligible change due to the predicted additional site traffic.

27 23 8. SECOND ACCESS 8.1 Background Winstone requested TDG assess the option of adding a second heavy vehicle access from the Three Kings quarry onto Mt Eden Road. This access was modelled to be in the general area between Kingsway and Grahame Breed Drive (with a distance of at least 30m to either intersection recommended for traffic separation reasons). The Second Access is to improve site connections to the road network by reducing volumes at the individual accesses as well as facilitating operations within the quarry by enabling access from different directions. Two possible scenarios were considered: Scenario 1: Two-Way, assumes that both access points can be used by trucks to both enter and exit the site (with the site traffic volumes being split evenly); and Scenario 2: One-Way, assumes that one access (the new Second Access point) is used by all trucks entering the site while the other access (existing, still called Site Access ) is used as an exit only. 8.2 Two-Way Scenario Site Access In this scenario, the existing Site Access is first analysed with half the future site traffic volume used in Section 7, to assess the benefits of such a site traffic reduction. Only the results of the South scenario modelling are presented, as it is this scenario which causes the most substantial delays at the site. The scenario also looks exclusively at the future as there is no current second access. The results are summarised in Table 13: Movement F1 AM South F2 AM South F1 PM South F2 PM South Mt Eden Rd N/B, left A A A A Mt Eden Rd N/B, thru A A A A Mt Eden Rd S/B, thru A A A A Mt Eden Rd S/B, right C E C E Site Access E/B, left C D C D Site Access E/B, right F F F F Table 13 : Mt Eden Road / Site Access, South Scenario Future The above results for 50% of all site traffic are to be compared to Table 6 in Section 7 (showing the performance of the existing site access with 100% of all site traffic). This comparison shows that the right turns in and out of the site have substantially improved. The delay improvements are variable, with delays improving by between 8 and 13 seconds for the right turn from Mt Eden Road, while the delays for the right turn out are significantly improved especially for the F 2 scenario, with the PM delays falling by almost half from 422 seconds to 229 seconds.

28 24 As expected, the above results show that a second site access would substantially improve the site traffic performance for the existing access. Specifically, it makes the existing access much more efficient during peak hours, when otherwise, long average delays accumulate Second Access The performance of a Second Access was also tested, which would most likely lie between Kingsway and Graeme Breed Drive. It was considered that it should not be placed directly opposite Kingsway due to the conflicting manoeuvres caused by opposing two-way intersection approaches. This Second Access was modelled identically to the Site Access, though with the changed flows existing further south on Mt Eden Road. Again, this assessment focused on the 2014 South scenarios. The results are summarised in Table 14: Movement F1 AM South F2 AM South F1 PM South F2 PM South Mt Eden Rd N/B, left A A A A Mt Eden Rd N/B, thru A A A A Mt Eden Rd S/B, thru A A A A Mt Eden Rd S/B, right D E D F 2nd Access E/B, left C D C D 2nd Access E/B, right F F F F Table 14 : Mt Eden Road / Second Access, South Scenario Future The above results should also to be compared to Table 6 in Section 7, ie: the existing Site Access with 100% of the site traffic. As expected, it was established that while most turning movements performed better than a single 100% site traffic Site Access, the southern Second Access shows worse delays for the right-turning movements out of the site than the existing Site Access at the same 50% volume. The reason for this is that the movements at the second site access have to give way to over a hundred more opposing vehicles on the through movements. This represents vehicles going to and from Kingsway, with these movements being more dominant towards the south, rather than past the existing site access. As a result, it can be noted that while a Second Access benefits the site operation, especially by reducing right turn delays at the existing Site Access, the delays at the Second Access would be problematic during peak hours. These delays are however contained within the site. 8.3 One-Way Scenario Site Access In this scenario, the existing Site Access is analysed with all exiting site traffic as in Section 7, but having no incoming site traffic (except the small number of cars described previously). The heavy vehicles now enter at the southern access. The results are summarised in Table 15:

29 25 F1 AM South F2 AM South F1 PM South F2 PM South Movement LO S LO S Mt Eden Rd N/B, thru A A A A Mt Eden Rd S/B, thru A A A A Site access E/B, left C D C D Site access E/B, right F F F F Table 15 : Mt Eden Road / Site Access, South Scenario Future The above results are to be compared to Table 6 in Section 7, showing the performance of the existing site access with 100% of all site traffic in the future scenarios. The results are as expected, with small improvements occurring for the movements turning out due to the lack of inbound movements to give way to. These improvements are however too minimal to substantially improve the peak time delays for the F 2 PM scenarios, which remain at very high levels Second Access To ensure that a worst case scenario was modelled, a Second Access has been assumed to lie directly opposite Kingsway. This was considered to be acceptable as a worst case, as there would be only entry manoeuvres into the site to conflict with opposing Kingsway manoeuvres. In reality, this Second Access may actually be situated at almost any location between Kingsway and Graeme Breed Drive without affecting the conclusions about effects on the network. The results for this combined Kingsway / Second Access intersection are summarised in Table 16: Movement F1 AM South F2 AM South F1 PM South F2 PM South Mt Eden Rd N/B, left A A A A Mt Eden Rd N/B, thru A A A A Mt Eden Rd N/B,right B B C C Kingsway, all turns C C C C Mt Eden Rd S/B, left A A A A Mt Eden Rd S/B, thru A A A A Mt Eden Rd S/B, right C E D E Table 16 : Mt Eden Road / Second Access, South Scenario Future The access performs as well as expected, as movements rarely give way to more than one opposing stream, except for the movements out of Kingsway. The Kingsway approach has negligible delay increases of around 1 second on average (compared to Table 8 for the Kingsway intersection). The through movements face minimal delays as heavy vehicles turn left into the site or vehicles decelerate to turn left into Kingsway.

30 26 As a result, it can be seen that a one-way circulatory system via a second access would work in so far that it reduces the delays for the entering movements, though these were rarely problematic before (compare Table 6 for the existing Site Access). In combination with the limited improvements to the exiting movements, most of the benefits derived from this solution would likely be operational (i.e. within the site with no direct effects on road network performance). 8.4 Section Summary The analysis shows that while there are advantages to a second access beyond operational benefits, the reductions in delay found do not change the general nature or order of magnitude of the delays. This applies to both the Two-Way and the One-Way scenarios. The limited nature of the benefits is partially due to the higher traffic volumes in the area of a possible new access, between Kingsway and Grahame Breed Drive. This also leads to the conclusion that reversing the one-way system would be less efficient, as it would lead to higher exiting delays at the second access than those shown in Table 6 for the existing access. This would also apply if the existing access were relocated to the south. In summary, a second access, whether used one-way or two-way, would provide some benefits, although not in such a manner as to provide double the effectiveness of a single access from a road network perspective.

31 27 9. CONCLUSIONS This study has established that the surrounding road network in general would see no noticeable change due to the projected site traffic, although some delays would be experienced by some turning movements at the site access. The results should be viewed in the context of the multiple robust projections of future peak conditions that have been deliberately combined. These include: accounting for seasonal fluctuations, the daily traffic activity of the site was estimated to be double that of the annual average; the peak hour of the site traffic was calculated to coincide directly and additively with the peak hour of the background traffic on Mount Eden Road; and the annual background traffic growth on Mount Eden Road was modelled to be 1.5% per year, whereas historical surveys establish a net reduction in traffic flows along Mt Eden Road over the last few years. It is therefore considered that such delays would not or very rarely be experienced in practice, as live management of vehicle egress times, management of schedules and routing would be adopted by the operator to address or avoid these peak time conditions. It is unlikely, therefore, that the site traffic would actually experience the difficulties that the modelling calculates. It is therefore concluded that there are no traffic engineering or transport planning reasons that would preclude the proposed operation of the development. In the analysis of a possible second access, it is considered that a second access would provide some benefit for the affected site traffic movements, and would be feasible in terms of the local road network. Traffic Design Group 12 June 2008