261 Twilight Road Cleanfill Application Review of Traffic Assessment

Transcription

1 Auckland Council 261 Twilight Road Cleanfill Application Review of Traffic Assessment

2 Auckland Council 261 Twilight Road Cleanfill Application Review of Traffic Assessment Prepared By John Neill Senior Traffic and Transportation Engineer Auckland South Office 15 Putney Way, Manukau, Auckland Po Box , Manukau 2241 New Zealand Telephone: Facsimile: Date: April 2014 Reference: OAS Status: Version 3 Approved for Release By Chris Freke Manager Auckland South 2014

3 261 Twilight Road Cleanfill Application Review of Traffic Assessment i Contents 1 Introduction Traffic Assessment Proposed Truck Movement to the Cleanfill Site Roads Evaluated in the Traffic Assessment Road Descriptions Traffic flows Review of Proposed Traffic Volumes Road Widths Twilight Road Between Kimptons Road and the Cleanfill Site Twilight Road between the Cleanfill Site and North Road Bridge on Brookby Road Road Classification Road Capacity Brookby Road and Twilight Road Intersection Cyclists Horses Recreational Use of the Roads Brookby School Parking Modifications at Brookby School Crashes Application for Brookby Quarry Conclusions The Application Access to 261 Twilight Road Road Capacity Road Widths Existing Bridges Road Crashes Brookby School Twilight Road West of the Cleanfill Entrance Twilight Road East of the Cleanfill Entrance Summary Recommendations... 21

4 261 Twilight Road Cleanfill Application Review of Traffic Assessment 1 1 Introduction This report is based on a review of the Application and Assessment of Effects on the Environment including the Traffic Impact Assessment provided by TEAM Traffic and subsequent information provided in the request for further information by Council under Section 92 of the Resource Management Act (RMA) and discusses the traffic issues associated with the application to operate a cleanfill site at 261 Twilight Road, Brookby. The total hours per week that the cleanfill will operate is 61. The applicant has estimated that the maximum traffic generation of the activity will be 240 truck movements per day (120 trucks into the site and 120 trucks leaving). They have estimated that the average truck movements (for a one month period) will be 160 trucks per day (80 trucks into the site and 80 trucks leaving). There is an existing clay extraction pit at 261 Twilight Road (clay extraction activity - Proposal 20054) where 40 truck movements (20 trucks into the site and 20 trucks leaving the site) per day from 1 October to 31 March the following year are permitted and this is proposed to continue in operation as it is in a different location to the proposed cleanfill operation, although on the same site. From 1 April to 30 September, the site (261 Twilight Road) as a whole will have the potential to generate an average of 160 movements per day, and a maximum of 240 truck movements per day. During the period from 1 October to 31 March the following year, the site (261 Twilight Road) as a whole will have the potential to generate an average of 200 truck movements and a maximum 280 movements per day. The proposed hours of operations are 7.00 am to 6.00 pm Monday to Friday and 7.00 am to 1.00 pm Saturday whilst the authorised operating hours of the clay extraction pit activity are 7.00 am to 6.00 pm Monday to Saturday. The existing traffic accessing the clay extraction pit 261 Twilight Road has no restrictions on the use of any road or road section. It is understood that the majority of trucks accessing the clay extraction pit head towards Brookby Road on Twilight Road rather than towards North Road. The application for the cleanfill is for all trucks to head towards Brookby Road on Twilight Road and that no trucks accessing the cleanfill site will head towards North Road due to the difficult alignment of Twilight Road over this section. There is likely to be a 50% split in traffic at the intersection of Twilight Road and Brookby Road with half going each way. Clearly this is going to vary from day to day depending on where the cleanfill is being sourced. The section of Twilight Road between Brookby Road and Kimptons Road has been upgraded and widened to the lane and shoulder widths recommended in Austroads. The remaining roads in the area, although classified as arterial roads, do not generally have sealed shoulders. The road geometric standard, capacity calculations and safety engineering have been assessed using Austroads. Austroads is a joint Australia and New Zealand roading design standard. It has been adopted by the New Zealand Transport Agency and most New Zealand road controlling authorities, including Auckland Transport, as an appropriate standard for roading in New Zealand. It is also referenced in the legacy Manukau District Plan as providing a practical solution for matters not covered by specific provisions.

5 261 Twilight Road Cleanfill Application Review of Traffic Assessment 2 2 Traffic Assessment 2.1 Proposed Truck Movement to the Cleanfill Site The applicant has estimated that the maximum traffic generation of the cleanfill activity will be 240 truck movements per day (120 trucks into the site and 120 trucks leaving). They have estimated that the average truck movements (for a one month period) will be 160 trucks per day (80 trucks into the site and 80 trucks leaving). This proposal adds traffic to the existing clay extraction pit operation at 261 Twilight Road which permits 40 truck movements (20 trucks into the site and 20 trucks leaving the site) per day from 1 October to 31 March the following year and this is proposed to continue in operation as it is in a different location to the proposed cleanfill operation, although on the same site. From 1 April to 30 September, the site as a whole will have the potential to generate an average of 160 movements per day, and a maximum of 240 truck movements per day. During the period from 1 October to 31 March the following year, the site as a whole, will have the potential to generate an average of 200 truck movements and a maximum 280 movements per day. 2.2 Roads Evaluated in the Traffic Assessment The traffic assessment received from the applicant has evaluated the effects of increased traffic flows on Twilight Road and its intersection with Brookby Road for capacity. Both these roads have adequate capacity for the proposed increase in traffic when evaluated using Austroads capacity guidelines. Other roads will be affected by the proposed increase in traffic flows but the effects on these roads have not been evaluated by the applicant. These roads include Brookby Road, West Road, Alfriston Road and Whitford Park Road. The overall seal width on these roads is generally narrow and although lane widths are greater than three metres and mostly 3.5 metres wide, sealed shoulders, other than a narrow strip of seal outside the edgeline, are generally absent.

6 261 Twilight Road Cleanfill Application Review of Traffic Assessment Road Descriptions The roads most affected by the application are listed below. The road hierarchy, carriageway, lane and shoulder widths have been taken from the RAMM database maintained by Auckland Transport. RAMM records the dimensions of the roads and is constantly being updated as the roads are upgraded. Accordingly this table is a good representation of the road carriageway widths. Speed limits have been obtained from the Auckland Transport Speed Limits Database. Name Section Hierarchy Speed Limit Lane Width Sealed Shoulder Widths Kimptons Road Twilight Road to Brookby Quarry Entrance Local 100 km/h 3.5 m 1.0 m Twilight Road Brookby Road to Kimptons Road Rural District Arterial 100 km/h 3.5m 1.0m Twilight Road Kimptons Road to North Road Rural District Arterial 100 km/h Less than 3m 0 Brookby Road Brookby Road Brookby Road Brookby Road Brookby Road Alfriston Road Whitford Park Road Whitford Park Road Alfriston-Ardmore Road to Fitzpatrick Road Fitzpatrick Road to West Road West Road to Twilight Road Twilight Road to Road Narrows Road Narrows to Whitford Park Road Mill Road to Alfriston- Ardmore Road Sandstone Road to Polo Lane Polo Lane to Brookby Road Rural District Arterial Rural District Arterial Rural District Arterial Rural District Arterial Rural District Arterial Secondary Rural District Arterial Rural District Arterial 100 km/h 100 km/h 100 km/h 100 km/h 100 km/h 80 and 100 km/h 100 km/h 100 km/h 3.5m 0.35m 3.5m 0.35m 3.5m 0.2m 3.5m 1.5m 3.0m 0.25m 3.5m 0.3m 3.5m 0.3m

7 261 Twilight Road Cleanfill Application Review of Traffic Assessment Traffic flows Traffic flows from the Auckland Transport Traffic Flow Database recorded in the vicinity of 261 Twilight Road are as follows: Road Name Location 5-day Average 7-day Average HCV% Date of Count Brookby Road Twilight Road Whitford Park Road Between Fitzpatrick Road and West Road Between Brookby Road and Kimptons Road Between Sandstone Road and Brownhill Road % December October % May 2012 The percentages of heavy commercial vehicles by day of the week have also been recorded for Kimptons Road and Brookby Road. Road Name Location of Count Brookby Road Between Fitzpatrick Road and West Road Date December 2012 Day Daily Traffic Flow (Both Directions) Heavy Commercial Vehicle Percentage Sun % Mon % Tue % Wed % Thu % Fri % Sat % 2.5 Review of Proposed Traffic Volumes Based on the application s maximum rate of truck flow to and from the site, traffic flows on the roads affected by this application will increase. While it is difficult to be precise, it has been calculated that the total traffic volumes and the heavy commercial vehicle percentages estimated if the resource consent is granted as applied for, will be approximately as shown in the table below.

8 261 Twilight Road Cleanfill Application Review of Traffic Assessment 5 The traffic flows have been expressed in averages for the whole week (seven days) to try and eliminate daily variances. No allowances have been made for other traffic growth and the values show the likely values that would have been recorded if the consent had been in place when the traffic counts were carried out. Opus Estimate of Traffic Volumes Road Name Location Existing 7-Day Average Existing HCV% Estimated 7-Day Average Estimated HCV% Date of Count Brookby Road Kimptons Road Twilight Road Whitford Park Road Between Fitzpatrick Road and West Road Between Twilight Road and End of Seal Between Brookby Road and Kimptons Road Between Sandstone Road and Brownhill Road % % Dec % % Dec % Oct % % May Road Widths Twilight Road between Kimptons Road and Brookby Road has been widened to approximately 9 metres seal width. This gives 3.5 metre wide lanes and 1.0 metre sealed shoulders and is considered an appropriate geometric standard as recommended by Austroads for the traffic composition that this road is carrying. The seal width on the section of Brookby Road between Alfriston-Ardmore Road and Twilight Road is between 7.4 and 7.7 metres wide as recorded in RAMM. RAMM is the Road Asset Maintenance Management database in use by Auckland Transport and all roading authorities in New Zealand, to record the features of roads. With 3.5 metre wide lanes there are minimal width sealed shoulders available. Brookby Road to the north of Twilight Road has been widened and has approximately 1.5 metre sealed shoulders for the first 800 metres after which the seal width reduces to 6.5 metres. Over this later section towards Whitford Park Road there are no sealed shoulders and the lanes are narrower than desirable. Whitford Park Road has predominantly 6.6 metres of seal width between Ara-kotinga and Polo Lane apart from a short section of approximately 300 metres immediately north of Ara-kotinga, where the shoulders have been widened. From Polo Lane to Sandstone Road the seal width is 7.6 metres giving 3.5 metre wide lanes and 0.3 metre sealed shoulders. The Austroads Guide to Road Design Part 3 Geometric Design Table 4.5 recommends that rural arterial roads carrying in excess of 3000 vehicles per day should ideally have 3.5 metre wide lanes and 1.5 metre wide sealed shoulder with a total shoulder width of 2.5 metres. Brookby Road,

9 261 Twilight Road Cleanfill Application Review of Traffic Assessment 6 Whitford Park Road, Sandstone Road and Alfriston Road all have traffic flows greater than 3000 vehicles per day already. An extract from the Austroads guide is shown below. Apart from a short section on Brookby Road, the cross sectional widths of the roads leading towards Twilight Road that will be used by the trucks accessing the proposed cleanfill, fall short of the minimum widths stated in Austroads. This has an impact on the overall safety of the roads particularly for alternative transport modes such as cyclists. It also contributes to the overall maintenance costs as the absence of sealed shoulders leads to pavement edge break and the need to grade the unsealed shoulders more regularly. Based on this analysis it is considered that there is a safety concern for vulnerable road users such as cyclists using these narrow roads and the truck numbers applied for may increase the possibility of crashes between trucks and these users. With sealed shoulders, as recommended in Austroads, there would be room for cyclists to cycle clear of the traffic lanes when other traffic is approaching. Providing shoulders will have benefits all week but particularly on Saturdays when there are more cyclists on the roads. 2.7 Twilight Road Between Kimptons Road and the Cleanfill Site The section of Twilight Road between Kimptons Road and the entrance to the cleanfill site is very narrow in some locations. The applicant is planning to make a financial contribution to meet the cost of widening works in these sections so that the road can operate safely with the increased truck numbers. The applicant s traffic engineer has identified these locations and preliminary drawings have been provided of this widening work. The proposed work will widen the traffic lanes to 3.0 metres minimum and slightly more on the smaller radius horizontal curves.

10 261 Twilight Road Cleanfill Application Review of Traffic Assessment 7 Traffic flows over this section of road are low and the provision of sealed shoulders is not considered essential. They would of course be desirable but the topography rules them out unless extensive earthworks and land purchase, at considerable cost, is undertaken. The traffic flow on this scenic route simply does not justify expenditure of this magnitude. 2.8 Twilight Road between the Cleanfill Site and North Road Between the cleanfill site entrance and North Road, Twilight Road traverses a section of very small radii curves and narrow cross section. This section is not suitable for the regular use of trucks although there are some trucks using this section of the road. The applicant has recognised this difficulty and is prepared to accept a condition that trucks accessing the cleanfill site do not use this section of the road. 2.9 Bridge on Brookby Road There is a bridge (Kimptons Bridge) on Brookby Road to the south of Twilight Road. This bridge, although two-way, is narrow. The width of the bridge between the bridge guardrails is 6.2 metres and the distance between the lane edgelines is 5.2 metres. There is a concern that two trucks meeting on this narrow bridge would need to slow considerably and proceed with caution. A car meeting a truck at the bridge would feel constricted. An observation of this bridge in operation has indicated that some vehicles move slightly to the other side of the road when travelling across the bridge if there is no oncoming traffic and shy away from the guardrails/handrails. If a cyclist and a truck were to use the bridge at the same time in the same direction, the cyclist would be well advised to wait until the way was clear. If two trucks and a cyclist or a car, a truck and a cyclist tried to use the bridge at the same time then it would simply not be wide enough for all three to use the bridge at the same time. As a minimum, signage is required on the approaches to this bridge to alert drivers to this narrow bridge. A wider bridge would be desirable, particularly for Saturday use when there are more recreational vehicles such as horse floats campervans and tourist vehicles present. A PW-44 sign (narrow road) should be erected when the width between kerbs, barrier rails or wheel guards is less than 6.1 metres (Manual of Traffic Signs and Markings [MOTSAM]). At this location there is 6.2 metres between the bridge guardrails so technically the PW-44 narrow road sign is not required. However given the expected percentage of heavy vehicles using the bridge as a result of this application and another application for the Brookby Quarry, it is considered prudent to install the signs Road Classification Section 8A1.5 of the Operative Auckland Council Plan Manukau Section lists the classification of roads. Brookby Road, Whitford Park Road, Sandstone Road and Twilight Road are classified as District Arterial (Rural Area) Roads. Appendix A2 of Chapter 9 contains widths for various categories of roads. This table does not cover rural arterial road widths and section of Chapter 9 refers to Austroads when the district plan does not have specific information on roading standards. The relevant paragraph is included below: In addressing the traffic engineering design issues described above, design solutions in accordance with the Councils Engineering Quality Standards, Transit New Zealand or AUSTROAD s guidelines

11 261 Twilight Road Cleanfill Application Review of Traffic Assessment 8 shall be generally acceptable, except where they are contrary to a specific provision of the District Plan or where they do not meet the foregoing assessment criteria. Thus it is considered appropriate to reference Austroads standards when assessing road geometry and capacities in this area Road Capacity The capacity of a road is dependent on the geometric quality of the road and the composition of the traffic stream using the road. The geometric factors are the lane width of the road, the horizontal curve radii, the vertical grades and the vertical curves lengths. The composition of the traffic is dependent on the number of vehicles in the traffic stream and the percentage of heavy commercial vehicles in the traffic stream. Heavy commercial vehicles occupy more space than light vehicles and are slower on grades, particularly steeper grades. The effect of heavy commercial vehicles in the traffic stream is expressed as passenger car units (PCU). This factor changes with different road conditions. For instance, an intersection where trucks need to stop, may have a PCU value of 10, whereas, a reasonably flat section of rural highway may have a PCU value of 2.0. The extract below from the Austroads Guide to Traffic Management Part 3 indicates PCU values appropriate for uninterrupted flow. Thus the section of Twilight Road between Brookby Road and Kimptons Road, where grades are almost flat, could be considered to have a PCU of 2.0, whereas the long, sustained grade on Whitford Park Road from Cemetery Bridge to the top of the hills in both directions could be considered to have a PCU value of 8. The other variables are the lane and shoulder widths and these are also given in Austroads Guide to Traffic Management Part 3 as indicated below. The formula for estimating the capacity of a traffic lane is contained in the following formula from Austroads:

12 261 Twilight Road Cleanfill Application Review of Traffic Assessment 9 The maximum capacity under ideal conditions for these rural roads could be considered to be 1800 vehicles per hour per lane. Because of the grades, the road width and the traffic composition, the actual capacity will be less than this. The following table indicates the estimated maximum hourly and daily capacity of the roads based on the existing heavy vehicle percentages. With reference to the measured daily traffic flows in Section 2.4 above, all of the roads are operating within their theoretical maximum capacity as indicated in the table. As the majority of traffic using these roads occurs during the day time, Whitford Park Road between Brookby Road and Cemetery Bridge is getting close to capacity due to the steep grades over this section and there are likely to be delays to light vehicles should they be following a truck over this section. To a lesser extent, the section of Brookby Road from Twilight Road to the top of the hill at Whitford Park Road will also be likely to experience delays Brookby Road and Twilight Road Intersection An analysis of the intersection at Twilight Road/Brookby Road using SIDRA was undertaken by the applicant. SIDRA is an internationally recognised software package for the analysis of intersections. The analysis indicates that there is adequate capacity at the intersections to absorb the traffic likely to be generated by this cleanfill application. There is also sufficient capacity for the expansion of the Brookby Quarry should that application be approved. In that scenario (ie both the Cleanfill and the Brookby Quarry applications being approved), there will still be adequate unused capacity for normal traffic growth for the foreseeable future.

13 261 Twilight Road Cleanfill Application Review of Traffic Assessment Cyclists Opus has carried out surveys of the cyclists using this area. It is known that many cyclists use the roads in this area. The weekends are the busiest times for cyclists and throughout the year a number of cycle events are organised for various roads in the Whitford/Brookby/Clevedon area. A survey of cyclists conducted by Opus on Brookby Road beside the school and in Whitford Park Road near to the intersection of Brookby Road in the morning on Saturday 14 September 2013 indicated a constant but low number of cyclists using the road. On this date the weather was showery and the forecast was for heavy rain in the afternoon. Recorded were six cyclists per hour at Brookby Road and four cyclists per hour on Whitford Park Road. Traffic flows were light and the cyclists were not observed to be having any difficulties with other traffic. It was also observed that there was a cycle activity in Clevedon and this may have diverted some cyclists from these roads to other roads. A further three hour survey carried out by Opus on Saturday 1 February 2014 from 06:30 am until 09:30 am recorded 53 cyclists (all turning movements) using the intersection of Brookby Road and Twilight Road. The significance of this location, for the purposes of the survey, was that three sections of the road network could be viewed from the one location. During the survey eight cyclists were recorded between 6:30 am and 7:30 am, 26 between 7:30 am and 8:30 am and 19 between 8:30 am and 9:30 am. The weather during this survey was very good. If a cyclist was travelling at 20km/h then it would take 14.3 minutes to travel from the intersection of Sandstone Road and Whitford Park Road to the intersection of Brookby Road and Twilight Road, a distance of kilometres. If the cleanfill was operating at their full applied-for rate of 22 movements per hour and there is a 50% split in trucks as predicted at the intersection of Twilight Road and Brookby Road, then each cyclist could be passed by between 1 and 2 trucks in each direction during the time it takes to cycle this distance Horses Horses are known to be in the area. There is a pony club at the intersection of West Road and Brookby Road. There are also pony clubs at Whitford and on Redoubt Road. Many of the farms and lifestyle blocks in the area are observed to keep horses. Horses are likely to be on the roads at times and this is more likely in the weekends. During the weekend site visits, horses have not been observed on Brookby Road but many horse transporters, both truck type and vehicles towing horse float trailers, were observed. With the narrow road cross sections there is likely to be conflict between motor vehicles and horses. Saturday operation of the cleanfill will increase the possibility of conflict to the degree that it exists Recreational Use of the Roads All roads in the area have a strong recreational use at certain times. Weekends particularly can see large numbers of cyclists using the roads either individually or as part of an organised event. The majority of the roading network does not have sealed shoulders and this results in motor vehicles and cyclists using the same space in the lane. More trucks on the roads are likely to have an effect on the safety of the cyclists. The provision of sealed shoulders would improve the safety of the roading network, particularly for cyclists. A count of cyclists carried out by Opus on 14 September 2013 revealed an average of six cyclists per hour using Brookby Road near to Brookby School and four cyclists per hour using Whitford Park Road. A further count by Opus on 1 February 2014 revealed an average of 18 cyclists per hour using the Brookby Road/Twilight Road intersection. This

14 261 Twilight Road Cleanfill Application Review of Traffic Assessment 11 count was carried out in excellent weather conditions whereas the September count was in very poor weather conditions. This indicates that cycle numbers vary depending on the time of year and the weather conditions. Only one pedestrian running was observed during the surveys conducted by Opus on Saturday 1 February It is noted that part of the Te Araroa walkway follows Brookby Road, Twilight Road and the length of Kimptons Road as indicated on the map below compiled by Boffa Miskell. Brookby Road and Twilight Road form part of a circuit used by Counties Manukau Cycling. While the cycling and pedestrian surveys did not reveal many pedestrians, from time to time pedestrians will be present on these road. The absence of sealed shoulder is not an issue for pedestrians as they are most likely to be walking well clear of the carriageway.

15 261 Twilight Road Cleanfill Application Review of Traffic Assessment 12

16 261 Twilight Road Cleanfill Application Review of Traffic Assessment Brookby School Brookby School is situated at the intersection of Brookby Road and West Road. The intersection beside the school is controlled by a roundabout. Angle parking exists beside the school on both West Road and Brookby Road. This requires parked vehicles to back out of the parking space onto the through road. Reversing manoeuvres are always more difficult than forward manoeuvres. For the angle parking area beside Brookby Road there is only 1.5 metres of clearance between the back of a parked vehicle in the parking bay and the through traffic lane, and drivers do from time to time experience trouble with this backing out manoeuvre. More separation between the parking bays to allow drivers of vehicles backing out of a parking space to see past the adjacent parked vehicle would improve safety of this parking area on Brookby Road. If additional separation cannot be achieved it may be necessary to change this right angle parking area to parallel parking. This may result in an undersupply in parking spaces for the school and could encourage the undesirable use of the northern side of Brookby Road for parking. Options to provide for additional separation between the parking spaces on Brookby Road and the traffic lanes are discussed in the next section. The school is provided with an active school warning zone. This does not legally reduce the speed limit past the school but does have a positive effect in lowering speeds during the time that the children are arriving and leaving. The proximity of the roundabout at West Road to the school also lowers speed considerably as vehicles are required to travel at low speeds to negotiate the intersection. The geometry of this roundabout could be changed to reduce approach speeds further. This is an issue for Auckland Transport as it affects all road users. Additional truck traffic past the school will increase the possibility of crashes between vehicles manoeuvring into and out of the parking area and through vehicles at school start and finish times. The speed limit past the school is the open road limit or 100km/h. While it is not practicable to travel at open road speeds because of the nearby roundabout, speeds in the area may be higher at times than desirable past a school. Auckland Transport has measured the 85 th percentile speed of trucks at 63km/h and 68km/h for all vehicles during the morning school start time. Opus has undertaken a further speed survey at the vehicle entrance to the school and has calculated an 85 th percentile speed of 66km/h for all vehicles travelling in both directions during the afternoon school finish time. Vehicles that stopped to pick up school children were excluded from this survey. Trucks were also identified in this survey and the 85 th percentile speeds of trucks were calculated at 64km/h for westbound and 55km/h for eastbound. These values are for all trucks as it was not possible to determine which trucks were associated with any particular activity. All of these 85 th percentile values are reasonably low for a 100km/h speed limit area. A speed count undertaken by Auckland Transport in February this year using traffic counting tubes has recorded 85 th percentile speeds just to the west of the school entrance as follows: Eastbound Westbound 24 Hours 86 km/h 80 km/h Morning School Peak Half Hour 68.9 km/h 71.8 km/h Afternoon school Peak Half Hour 70.2 km/h 67.9 km/h

17 261 Twilight Road Cleanfill Application Review of Traffic Assessment 14 This equates reasonably well with the manual speed surveys carried out at the school entrance by Auckland Transport and Opus. The speed limit on Brookby Road has been reviewed by Auckland Transport, and previously Manukau City Council, however the speed limit outside the school has never qualified for a lower speed limit. Speed limits are determined using guidelines set down by the New Zealand Transport Agency (NZTA). The aim is to have consistent speed limits in similar circumstances nationwide so that drivers are not deceived by an unusual speed limit. 40km/h variable speed limits in school zones are detailed in Traffic Note 37 Revision 2 May 2011 and active school warning signs are detailed in Traffic Note 56 Revision 1 January Brookby School is provided with active school warning signs. These signs have flashing orange lights during school start and finish times to warn drivers that here could be children in the area. They do not change the speed limit. There is angle parking on West Road for this school as well. This operates well because there is greater separation between the parking spaces and the through traffic lanes. West Road is classified as a Rural Collector Road and carries approximately 1700 vehicles per day, considerably less than Brookby Road. Auckland Transport has identified that safety at this school needs to be improved and will be looking at options to improve safety at the school. They are considering threshold treatments on Brookby Road and West Road beyond the school boundaries to encourage lower speeds past the school. At this stage changes to the parking area on Brookby Road are not being considered Parking Modifications at Brookby School Modification to the parking area in front of the school on Brookby Road are possible. For the angle parking to operate safely, there needs to be more separation between the through lanes and the angle parking spaces. An additional 1.5 metres would achieve a 3.0 metre separation between the back of parked vehicles and the through traffic lane. This is the amount of space required to allow drivers backing out of a right-angle parking space to see past the vehicle parked beside them and observe oncoming traffic before reversing into the through traffic lane. There have been no crashes in this parking area but this does not mean that safety should not be improved. Two options are available to provide additional separation. A third option is available to convert the existing right-angle parking to parallel parking and to provide additional parking in West Road. A parking restriction on the northern side of Brookby Road past the school should be considered for all options as this would remove the need for people to cross the road to parked cars on the northern side Option 1 Realign Brookby Road further to the north to provide the separation between the traffic lanes and the car parking spaces. This would require the piping of a deep drainage channel and the installation of a guardrail on the northern side of the road. With this method an additional 1.5 metres could be provided to give the required separation. A No Parking restriction on the northern side is also necessary as a shoulder wide enough for parking could not be provided.

18 261 Twilight Road Cleanfill Application Review of Traffic Assessment Option 2 Take approximately 1.5 metres from the school frontage and move the parking spaces forward to give the separation between the parking and the through traffic lanes Option 3 Change the existing right-angle parking in Brookby Road to parallel parking. Install a No Parking restriction on the northern side of Brookby Road and provide additional parking on West Road to make up the shortfall. This is the preferred option. Aerial view of the school and the parking area on Brookby Road.

19 261 Twilight Road Cleanfill Application Review of Traffic Assessment Crashes The following crashes have been recorded in the CAS database around the roads affected by this application: Road name Fatal Serious Minor Non-injury Total Twilight Road (Brookby Road to Kimptons Road) Twilight Road (Kimptons Road to North Road) Brookby Road Whitford Park Road The CAS database is administered by the New Zealand Transport Agency and is populated from the Police Traffic Crash Reports. The crash numbers on Brookby Road and Whitford Park Road are high enough to be of concern. Each of these roads have recorded 23 crashes in a five year analysis period, 2008 to On both roads loss of control is a significant cause of the crashes, there being 18 (78%) on Brookby Road and 10 (43%) on Whitford Park Road. The high incidence of these loss of control crashes may be attributed to the absence of sealed shoulders on these roads. Two of the loss of control crashes on Brookby Road involved heavy vehicles. Both were on the curve immediately south of Whitford Park Road, one in each direction. No loss of control crashes involving heavy commercial vehicles have been recorded on Whitford Park Road within the five-year analysis period. The section of Twilight Road to the east of Kimptons Road also has a high incidence of loss of control crashes. Seven of the nine (78%) crashes over this section are recorded as loss of control. Traffic flows on this section are low and the underlying cause of these loss of control crashes is likely to be the narrow road cross sectional width and the very substandard horizontal and vertical geometry of the alignment. These loss of control crashes have not involved heavy vehicles. Six of the crashes have occurred on the section to the east of the entrance to 261 Twilight Road. Twilight Road between Brookby Road and Kimptons Road has a very low incidence of crashes. The probable reason for this low crash rate is the better geometry of the road, the lower traffic volume and the presence of sealed shoulders. The New Zealand Transport Agency has developed a system known as KiwiRAP. This rates the Collective and Personal Risk of each road and these have the following definitions: Collective Risk = fatal and serious crashes per year per kilometre Personal Risk = fatal and serious crashes per year per 100 million vehicle kilometres

20 261 Twilight Road Cleanfill Application Review of Traffic Assessment 17 Collective Risk highlights which road links have a high number of fatal and serious crashes on them. This can be used to help determine where the greatest road safety gains can be made from investment in engineering. Collective risk is perhaps of most interest to the road controlling authorities as this highlights where infrastructure improvements are most likely to be cost effective. Auckland Transport has applied these principles to significant Auckland Council roads and the main roads affected by the Brookby Quarry Application have the following ratings. Brookby Road o Collective Risk = Medium-High (0.148) o Personal Risk = High (14.9) Alfriston Road o Collective Risk = Medium-High (0.117) o Personal Risk = Medium (6.6) Whitford Park Road o Not rated as there are only minor and non-injury crashes recorded in this road. The analysis needs fatal and serious crashes to be present and without these, the ratings become zero. This indicates that Brookby Road in particular is experiencing problems with the existing traffic volumes Application for Brookby Quarry Another application has been received by Auckland Council for the expansion of the Brookby Quarry situated in Kimptons Road. Kimptons road is off Twilight Road and so the traffic accessing the proposed cleanfill will be joined by traffic from the quarry from the intersection of Kimptons Road and Twilight Road on. The quarry s existing consent allows for 1800 truck movements per week, week-days only. They also have a maximum hourly rate of 80 movements and a daily maximum of 360 movements. The application is to increase to 5120 movements per week and add Saturday operation as well. Weekday operation requested is from 7:00 am until 6:00 pm and Saturday operation is 7:00 am until 4:00 pm. Apart from Kimptons Road, the trucks accessing this quarry will use the same roads as the cleanfill application. The combined effect of maximum truck flows from both applications has been considered when considering road lane capacities and intersection capacities. With both applications combined there is adequate capacity at all locations on the road network. This application is still being processed and the outcome is not known at this stage.

21 261 Twilight Road Cleanfill Application Review of Traffic Assessment 18 3 Conclusions 3.1 The Application P and I Pascoe Limited have filed an application for a cleanfill site at 261 Twilight Road. They have applied for a total of 240 truck movements per day, which is 120 into and 120 out of the cleanfill site. They have requested this over six days each week with the operating hours of 7:00 am to 6:00 pm weekdays and 7:00 am to 1:00 pm Saturdays. This gives a total of 61 hours of operation each week. There is an existing clay extraction operation occurring at a different location on the same site and this is planned to continue. The conditions for this clay extraction allows for 40 truck movements per day, Monday to Saturday 7:00 am to 6:00 pm. The consent allows for this operation from 1 October to 31 March the following year with a 814 maximum number of truck movements each year. 3.2 Access to 261 Twilight Road The roads that will be used to transport material to the proposed cleanfill site at 261 Twilight Road part of Twilight Road, Brookby Road, Whitford Park Road, Sandstone Road and Alfriston Road. After the intersection of Twilight Road and Brookby Road there is a split in truck traffic and some trucks travel to their destinations via Whitford and others via Brookby and Alfriston. Further away the trucks will become more dispersed as more route options open up to them. 3.3 Road Capacity Capacity checks have been carried out on the roads to be used by the trucks accessing the cleanfill. All roads have been found to have adequate capacity for the expected increase of truck numbers. These checks have also been carried out adding in the expected truck numbers for the expansion of the nearby quarry and there is still adequate capacity on these roads. Because trucks move slowly on uphill sections of roads, delays in travel time can be expected to other vehicles caught behind the trucks. 3.4 Road Widths Apart from Twilight Road and a few short sections of Brookby Road, the roads in this area do not have usable sealed shoulders. Shoulders are desirable for the safe operation of the roads. Shoulders become more necessary as traffic flows increase, if the composition of the traffic stream contains high numbers of heavy commercial vehicles and if there are cyclists present in the traffic stream. With the proposal for trucks assessing the cleanfill site at 261 Twilight Road to use Brookby Road and Whitford Park Road and with the truck usage by other operations nearby, the percentage of heavy commercial vehicles is higher on these roads than most other rural roads in this area. Sealed shoulders are most desirable on Whitford Park Road and Brookby Road as heavy commercial vehicles at 2.5 metres wide occupy a greater width of the lane than light vehicles such as cars. If a lane is 3.5 metres wide, then there is only 0.5 metres clearance either side of the heavy vehicle. This leaves little room for other users such as cyclists. Cycle numbers are low during week days and the increase in truck numbers due to this application and others in the area should not be a problem. However, for Saturday operation of the cleanfill, when there is higher level of cycling activity, will increase the conflict between cyclists and heavy commercial vehicles. Sealed shoulders on Whitford Park Road and Brookby Road would remove this

22 261 Twilight Road Cleanfill Application Review of Traffic Assessment 19 conflict and should be provided before the full number of truck movements applied for to and from the cleanfill are permitted on Saturdays. Auckland Transport does not have shoulder widening projects or road upgrading of roads in this area on its current forward works programme. The weekday operation of the existing trucks on these roads indicates that trucks and cyclists can use the road together so long as the total numbers of trucks are kept to a reasonable level. The current consent for nearby Brookby Quarry allows for 360 truck movement per weekday. This is a fair indication of the level of truck operation that could be tolerated on Saturdays before possible problems arise. While it would be desirable for no Saturday operation of the cleanfill, as any crash with cyclists is likely to cause serious injuries, a maximum of 84 truck movements on Saturday can be added to the other existing trucking operations in the area without overloading the network. This equates to seven movements in and seven out per hour. The total truck movement numbers for the Saturday operation is based approximately on the average daily weekday movements requested by the applicant, and applying this rate to the six hours of operation requested for Saturday. 3.5 Existing Bridges The narrow two lane bridge on Brookby Road (Kimptons Bridge) is expected to operate satisfactorily but it does need warning signage to alert other motorists to this narrow bridge. 3.6 Road Crashes The crash rates on the roads around the cleanfill site are generally low but Brookby Road is a concern as demonstrated by its KiwiRAP Collective Risk rating. The construction of sealed shoulders would benefit all vehicles, not just the quarry trucks and cyclists. 3.7 Brookby School The parking area on Brookby Road in front of Brookby School does not have a recorded crash problem but angle parking on a rural arterial is undesirable from a safety perspective. Auckland Transport are currently looking at safety improvements at this school. A modification of this parking area is not being considered as part of these safety improvements as there are no recorded crashes associated with the parking area. The safety improvement works are limited to installing threshold treatments either end of the school on Brookby Road and on West Road to slow traffic. The conversion of this angle parking area to parallel parking and the banning of parking on the northern side would be a positive safety improvement. The school currently has active warning signs which warn motorists of the presence of children at school start and finish times. They are not speed restriction signs. Speeds past the school are generally low at school start and finish times as indicated in the speed surveys carried out and higher during the rest of the day. It would be desirable for cleanfill trucks to be restricted to 40km/h past the school at start and finish times by a site agreement with the cleanfill operation as the increase in truck numbers increases the risk of a crash between trucks and manoeuvring vehicles. A voluntary speed of 40 km/h for cleanfill trucks should reduce the possibility of crashes. 3.8 Twilight Road West of the Cleanfill Entrance The section of Twilight Road from Brookby Road to Kimptons Road has been widened and is fit for the purpose of truck access to the cleanfill site. From Kimptons Road towards the cleanfill site

23 261 Twilight Road Cleanfill Application Review of Traffic Assessment 20 entrance the alignment is reasonably good for the first 660 metres. The next 880 metres is narrow with small radius curves and requires widening. A six metre wide carriageway should be provided but it will not be possible in this terrain to provide sealed shoulders. 3.9 Twilight Road East of the Cleanfill Entrance The horizontal and vertical alignment of Twilight Road between the cleanfill site entrance and North Road is poor and cleanfill trucks should not use this road. The application for the cleanfill has recognised this difficult alignment and has offered not to use this section of the road Summary The traffic analysis indicates that the proposed cleanfill truck numbers can be accommodated during the week days with small improvements to the road network. There is no recorded conflict between cyclists and trucks on a Saturday as trucks numbers are currently low. It is undesirable to allow for full number of truck movements requested in this application to occur on Saturdays until the roads are improved with the addition of sealed shoulders on Whitford Park Road and Brookby Road, however a maximum of 14 movements (7 in and 7 out per hour) giving a total of 84 per day on Saturdays is acceptable given the current roading conditions.

24 261 Twilight Road Cleanfill Application Review of Traffic Assessment 21 4 Recommendations It is recommended that this application is granted subject to the following conditions and/or measures being implemented: 1. Truck movements should be limited to 84 per day and 14 per hour (7 in and 7 out of the cleanfill) on Saturdays until such time as appropriate width sealed shoulders can be provided on Brookby Road and Whitford Park Road. 2. Truck speeds past Brookby School should be limited by a cleanfill site agreement to 40km/h while the active school zone warning signs are illuminated with flashing yellow lights. 3. Trucks accessing the cleanfill should not use Twilight Road between Kimptons Road and North Road. The following measures are considered desirable but will need to be addressed by Auckland Transport: 1. The right angle parking area outside Brookby School should be converted to parallel parking and the shortfall in parking made up with additional appropriate parking in West Road. 2. A No Stopping At All Times zone installed on the northern side of Brookby Road outside the school to prevent parking in this area. 3. The narrow two-lane bridge on Brookby Road (Kimptons Bridge) be provided with appropriate warning signage to inform drivers.

25 15 Putney Way, Manukau, Auckland Po Box , Manukau 2241 New Zealand t: f: w: