traffic impact study: doornvallei...

TRAFFIC IMPACT STUDY: Doornvallei x7

Irene Area, Pretoria

September 2017

Quality Management

Project Name Traffic Impact Study:

Doornvallei x7

Date of issue September 2017

Version 2

Prepared by: Skhulile Mashele (BSc Eng. Civil Engineering)

Avinash Menon

(BEng Civil Engineering, MEng Transportation

Systems, MTRP)

Reviewed by:

Ivandra Udoyen Pr Eng

(BSc Civil Engineering)

Client:

Consultant:

Tel: 011 262 2785 Fax: 086 679 3575 Email: [email protected] Sandhavon Office Park, Pongola Crescent, Block D, Sandton, Johannesburg, 2031

http://www.m-t.co.za/

TRAFFIC IMPACT STUDY Doornvallei x7

Koleko Solutions Version 2 – September 2017

i

Contents

1 Introduction 1

2 Background 1

3 Purpose of the Study and Scope of Work 2

4 Development Location and Land Use 2

5 Access to the proposed development 3

6 Existing Surrounding Road Network 4

7 Future Road Network 5

8 Peak Hours Analyses 5

9 Analyses Scenarios and Analysis Parameters 6

10 Existing Traffic Volumes 7

11 Development Trip Generation 8

12 Trip Distribution and Trip Assignment 8

13 Traffic Impact and Capacity Analyses 9

14 Public Transport 10

15 Conclusion and Recommendations 11



ii

Annexures

Annexure A Site Layout Plan

Annexure B Figures

Annexure C Tables: Summary of analyses results



1

Doornvallei x7

TRAFFIC IMPACT STUDY

Description Reference

1 Introduction

M&T Developers are planning to implement a residential development called Doornvallei x7 in the Irene area in City of Tshwane.

Koleko Solutions (Pty) Ltd was appointed to conduct the traffic impact study for the proposed Doornvallei x7 development. The study investigated the impact of the additional traffic generated by the proposed development rights on the immediate surrounding road network and determined whether any road and/or intersection upgrades are required to accommodate the anticipated traffic.

The impact of existing latent rights (approved rights but not yet implemented) have been considered to determine the cumulative traffic impact on the surrounding roads. Comments were also made in respect of the site access and public transport provision.

2 Background

The proposed development will comprise of 315 residential units. The proposed development is sandwiched between the existing Irene Glen Estates and the proposed Doornvallei x5 and x6 developments.

The Doornvallei x5 and x6 studies comprised of 315 residential units which were envisaged to be implemented in the following 2 phases:

• Phase 1: 150 residential units on Doornvallei x 5; and • Phase 2: 165 residential units on Doornvallei x 6.

A Traffic Impact Study was carried out for this development which yielded the following recommendations:

The Hillyfield Boulevard/ M57 intersection will require the following road upgrades:

• Construction of exclusive right-turn lanes on the north and south approaches of the intersection (on the M57 Road);

• Construction of an exclusive right-turn and left-turn lanes on the west approach of the intersection (Hillyfields Boulevard); and

• Signalization of the intersection.

In terms of public transport provision it is recommended that public transport laybys be constructed downstream of the M57/

Annexure A and

Figure 1 (Annexure B)



2

Doornvallei x7 TRAFFIC IMPACT STUDY


Hillyfields road intersection. Pedestrian walkways should be constructed from the entrance of the development up to M57/ Hillyfields Boulevard intersection.

The Gauteng Department of Roads and Transport and the City of Tshwane approved the traffic impact study in July 2016. The aforementioned road upgrades will be implemented as a part of the Doornvallei x5 and x6 developments. The extent of the upgrades at the above intersection was increased to make provision for the trips generated by the proposed township Doornvallei X7.

In this study, the proposed road upgrades for Doornvallei x5 and x6 were included in the analysis and termed “committed road network”.

3 Purpose of the

Study and Scope of

Work

The purpose of the traffic impact study is to assess the impact of the proposed development traffic on the surrounding road network and to provide professional traffic related recommendations and mitigation measures where necessary in order to obtain the required approval for the proposed land use rights for Doornvallei x7.

The methodology of the traffic assessment consists of the analyses of the road network and intersections surrounding the proposed development.

-

4 Development

Location and Land

Use

The proposed development is located within the City of Tshwane Municipality, opposite the St George’s Hotel, to the west of the R21.

The total development area is approximately 21.1 ha which will consist of 315 residential units. The extent of the land use rights per township is shown in Table 3.1.

Table 3.1: Extent of land use

Phase Development Phase Land Use Area

(ha) Extent (units)

2 Doornvallei x7

Residential Units 21.1 315

TOTAL 21.1 315

The layout plan for Doornvallei x7 is shown in Annexure A.

Annexure A



3



5 Access to the

proposed

development

The development will have one communal access via Hillyfields Boulevard. Initially access to this development will be provided off the M57, which is a Provincial Class 2 road which serves a mobility function. Hillyfields Boulevard is an existing access road and it currently used by the traffic coming from the Irene Glen Private Estate (to the north). The spacing between the entrance to the proposed development and the access on the M57 is approximately 365m.

The proposed K54 planned in the area will improve the west-east linkage in the area. According to Gauteng Department of Roads and Transport officials, the K54 is not expected to be built in the next 5 years. However, once the K54 is built, the access to the existing Irene Glen Estate (Hillyfields Boulevard) would be reinstated via Amoretta Street. Doornvallei x7 would also use the Amoretta access once the K54 is built.

Annexure A



4



6 Existing

Surrounding Road

Network

The following existing surrounding roads might be impacted by the new trips generated by the proposed development.

• M57:

The M57 is a Class 2 undivided 2 lane cross-sectionprovincial road. The road is located to the south of theproposed development and crosses the R21 (grade-separated) north-east of the proposed development. Theroad currently has high mobility function with someaccessibility function. In the vicinity of the proposeddevelopment, this road provides access to the SaintGeorge’s Hotel. The M57 is currently aligned to cater forregional north-south traffic movements. Generaly theroad carries ± 850 vehicles during the AM and PM peakhours.

• Sterkfontein Avenue:

Sterkfontein Avenue is a Class 3 tared road, with onelane per direction. The road follows a north-southaligments and it is situated to the east of the Doornvalleidevelopment. The road intersects with the M57, servingas an alternative north-south link.

• 24th Street:

24th Street is a class 5 road access road which forms anintersection with the M57, to the south of the proposeddevelopment. The road is a west-east link which carriesrelatively low traffic volumes (less than 20 vehicles duringthe peak hours). The road carries relatively low trafficvolumes (less than 50 vehicles/hour) during theweekday AM and PM peak hours.

The surrounding road network can be seen in Figure 3, Annexure B and the road classification

Figure 3, Annexure B



5



7 Future Road

Network

• K54.34 (Conventional Dual Carriageway):

The K54 is a proclaimed provincial road that will provide west-east linkage regionally. This route will be aligned south of the proposed development and will in future provide access to the proposed development on Doornvallei x7.

Figure 6.1 shows the future alignment of the K54 route.

Figure 6.1: Alignment of the future K54

Source: Google Earth

Figure 6.1

8 Peak Hours

Analyses

The critical peak hour or critical traffic scenario, from a road capacity point of view, occurs when the traffic generated by the development is a maximum or when the highest combination of existing street traffic and traffic generated by the development occurs. Based on the expected trip generation and traffic volumes on the surrounding road network, the critical peak hours on the surrounding road network will occur during the weekday morning peak hour and weekday afternoon peak hour.

M57

Proposed development

R21



6

9 Analyses Scenarios

and Analysis

Parameters

The following scenarios were analysed within the report:

• Scenario 1: 2016 AM and PM peak hour base year trafficvolumes and analysis results. Refer to Figures 3, 4 and5. This scenario will determine existing intersectionoperating conditions and road upgrade requirements forthe year 2016 AM and PM peak hour traffic volumesbased on the existing geometry and intersection control.

• Scenario 2: 2016 AM and PM peak hour base year trafficincluding the Doornvallei x7 proposed development tripsand analysis results. Scenario 2 determines existingintersection operating conditions and road upgraderequirements for the year 2016 AM and PM peak hourtraffic volumes considering the proposed developmenttraffic. The analysis results for Doornvallei x7 proposeddevelopment are shown in Figures 9 and 10.

• Scenario 3: 2021 AM and PM peak hour base year trafficwhereby a growth rate of 1.5% was applied on thesurrounding road network. This scenario determines theimpact of the 2021 AM and PM peak hour traffic volumeson the surrounding road network. Latent rights were alsoapplied on this scenario as per the other proposeddevelopments in Doornvallei x5 and x6. Figures 11 to 12show the capacity analysis results.

• Scenario 4: This scenario refers to the analyses of theprojected 2021 AM and PM peak hour traffic volumes,when the proposed development is fully implemented. Agrowth rate of 1.5% per annum was applied to thesurrounding road network; Doornvallei x5 and x 6 tripswere applied as latent rights. This scenario ultimatelydetermines the intersection operating conditions androad upgrades requirements for the future year trafficvolumes. The analysis results can be seen in Figures 13and 14.

Analyses parameters

The assessment of the traffic impact was done based on the following parameters:

Levels of service (LOS) at intersections: Is a measure of intersection performance determined based on the average delay at intersections. In most rural and urban areas an overall LOS of A to D is acceptable. LOS E or F are considered to be undesirable. The LOS definitions based on vehicle delay at intersections are provided in Table 8.1.

Figures 3 to 5 and 9 to 17 Annexure B



7



Table 8.1: Levels of Service definitions based on vehicle delay Levels of Service

Control Delay per Vehicle in Seconds

Levels of Acceptability

A 0 < d ≥ 14.5 Acceptable B 14.5 < d ≥ 28.5 Acceptable C 28.5 < d ≥ 42.5 Acceptable D 42.5 < d ≥ 56.5 Acceptable E 56.5 < d ≥ 70.5 Unacceptable F 70.5 < d Unacceptable

Delay: is a measure of intersection or roadway performance. It is the measure of driver discomfort, frustration, fuel consumption and lost travel time. Delay at intersections depends on various factors such as type of signal control, volume of traffic and volume/capacity ratio of each approach at an intersection

Volume / Capacity Ratio (v/c): A measure of intersection or roadway performance. It is the ratio of number of vehicles on the road to the available capacity of the roadway. The intersection capacity in the study area will be rated based on the volume/capacity ratio. According to the National Department of Transport Manual for Traffic Impact Study, the intersection capacity should be evaluated as follows:

• v/c<1: the intersection operates under capacity,• v/c=1: the intersection operates at capacity,• v/c>1: the intersection operates over capacity,

Road upgrades should be investigated when the v/c ratio exceeds 0.95.

10 Existing Traffic

Volumes

Traffic counts were carried out on Wednesday the 7th of September 2016. The peak hours were found to be the following:

AM peak hour: between 06:45 to 07:45; and

PM peak hour: between 16:30 to 17:30.

The following intersections were surveyed:

1. M57 / Sterkfontein Avenue,2. M57 / Access Road3. M57 / 24th Street.

Figures 3 to 5

Annexure B



8



The existing traffic volumes, during the AM and PM peak hours are indicated in Figures 4 to 5. The existing intersection configuration can be seen in Figure 3.

11 Development Trip

Generation

The expected trip generation by the proposed residential development on Doornvallei x7 was estimated based on the trip generation rates recommended in the South African Trip Data Manual (COTO, 2012). The trip generation tables are provided in Table 1, Annexure C.

The total trip generation by the proposed development is likely to be as follows:

1. Weekday AM Peak Hour:• 79 vehicle trips IN.• 236 vehicle trips OUT.• Total trips generated is 315 vehicles/hour.

2. Weekday PM Peak Hour:• 221 vehicle trips IN.• 95 vehicle trips OUT.• Total trips generated is 315 vehicles/hour.

Annexure C

12 Trip Distribution and

Trip Assignment

Assumptions with respect to the expected trip distribution were based on the location of the site access in relation to the surrounding road network, the existing traffic volumes, travel patterns as well as the land use nature of the proposed development.

Figure 6 depicts the expected trip distribution of the proposed development. The expected development trip assignment is shown in Figure 7 and 8, for the AM and PM peak hours respectively.

Figure 6

Annexure B



9



13 Traffic Impact and

Capacity Analyses

TRAFFIX, a micro-analytical network analysis tool, was used to assess the impact at the following intersections:

M57 / Sterkfontein Avenue; M57 /access to St. George’s Hotel/ access to the

proposed development; and M57 / 24th Street.

Analyses results:

Scenario 1 – 2016 Background Traffic.

All three intersections under investigation operate atacceptable level of service (LOS < D) and undercapacity.

Scenario 2 – 2016 AM and PM peak hour base year traffic including the Doornvallei x7 proposed development trips.


Scenario 3 - Projected 2021 AM and PM peak hour traffic volumes including the full development trips (Inclusive of Doornvallei x5 and x6 Trips as latent rights plus a growth factor of 1.5%).


The capacity analyses results are summarised in Table 2, Annexure C. The detailed outputs results are enclosed in Annexure B.

Figures 4 & 5;

Figures 9 & 10;

Figures 11-15,

Figures 16 & 17

Annexure B

and

Annexure C



10



14 Public Transport

The following short term and long term recommendation were made in the Doornvallei x5 and x6 traffic impact study.

Short term public transport provision:

Public transport laybys: Construction of mini-bus taxi lay-bys downstream of the intersection of the M57 and the access to the proposed development. The public transport lay-bys should accommodate at least 2 mini-bus taxis and it will be implemented as part of the infrastructure provision for Doornvallei X 5 and 6.

Paved sidewalks: In order to formalise and ease the movement of pedestrians between the site and the nearest public transport services, it is recommended that a paved sidewalk of at least 1,5m wide be constructed from the entrance to the development to the main access on M57. These sidewalks will be provided as part of the infrastructure provision for Doornvallei X 5 and 6.

The developer is responsible for providing the sidewalks and the public transport laybys.

Long term public transport provision:

Once the K54 is implemented, public transport provision for the area should be re-evaluated taking into account future public transport plans.

This responsibility lies with the provincial and local authorities.

In terms of this study, no further recommendations were made.



11



15 Conclusion and

Recommendations

Based on the findings of this investigation, the following can be concluded:

• The proposed development consists of 315 residentialunits.

• As a result, 315 new trips will be added to the existingsurrounding road network during the AM and PM peakhours.

• The impact of the added trips, upon the surrounding roadnetwork, was investigated for the following scenarios:

o Scenario 1: The existing 2016 backgroundtraffic without the proposed development trips.

o Scenario 2: The existing 2016 AM and PM peakhour base year traffic including the Doornvalleix7 proposed development trips.

o Scenario 3: The 2021 AM and PM peak hourbase year traffic including the full Doorrnvalleidevelopment trips (x5 and x6) as latent rightsplus a growth factor of 1.5% applied globally onthe 2016 AM and PM existing base year trafficvolume.

o Scenario 4 - Projected 2021 AM and PM peakhour traffic volumes including the fulldevelopment trips (Doornvallei x5, x6 and x7plus a growth factor of 1.5%).

• The proposed development will gain access fromHillyfields Boulevard from the M57.

• Once the K54 is built, the access to Irene Glen Estatesand Doornvallei x7 should be reinstated. GautengDepartment of Roads and Transport would bear theresponsibility and the cost of this exercise.

The following constitute the findings of the investigation:

• Currently all intersections under investigation (includingthe intersection which will be upgraded under DoornvalleiX 5 and 6) operate under capacity.

• The intersections will most likely continue to operateunder capacity in scenario 2 (2016 Existing AM and PMPeak Hour Volumes with Development Traffic).



12



• The intersections continue to operate under capacity inthe 2021 Background Traffic Scenario (growth + latentrights). No road upgrades were found to be required.

• No road upgrades were found to be required toaccommodate the traffic from Doornvallei x7development, as the road upgrades which will be donefor Doornvallei X5 and 6 make provision for DoornvalleiX7

• No upgrades to accommodate public transport and non-motorised transport were found to be required.

From a traffic engineering perspective, the proposed development on Doornvallei x7 is supported, provided the upgrades proposed in the Doornvallei x5 x6 traffic study be implemented.


Annexures

Annexure A Site Layout Plan

Annexure B Figures

Annexure C Tables: Summary of analyses results


Annexure A

Site Layout Plan


Annexure B

Figures

Figure 1: Regional Road Network

Figure 2: Study Area

Figure 3: Committed Geometry

Figure 4: 2016 Existing AM Peak Traffic Volumes and Capacity Analysis Results (Committed Geometry)

Figure 5: 2016 Existing PM Peak Traffic Volumes and Capacity Analysis Results (Committed Geometry)

Figure 6: Expected Trip Distribution

Figure 7: Expected Trip Assignment – AM Peak Hour

Figure 8: Expected Trip Assignment – PM Peak Hour

Figure 9: 2016 AM plus Development Traffic Volumes and Capacity Analysis Results

Figure 10: 2016 PM plus Development Traffic Volumes and Capacity Analysis Results

Figure 11: 2021 AM Background Traffic Volumes and Capacity Analysis Results

Figure 12: 2021 PM Background Traffic Volumes and Capacity Analysis Results

Figure 13: 2021 Total AM Traffic Volumes plus Full Development and Capacity Analysis Results

Figure 14: 2021 Total PM Traffic Volumes plus Full Development and Capacity Analysis Results

Koleko Solutions TRANS PORT ATI ON E NGI NEE RING / PLANNING


Annexure C

Tables - Summary of Analyses Results


DEVELOPMENT TRIP GENERATION Table 1: Proposed Development Total Trip Generation – Wednesday AM Peak Hour

No Extension Land Use Extent (units)

Trip Generation

Rate

Directional Split Trips Generated

In Out In (vph)

Out (vph)

Total (vph)

1 Irene Ridge Residential Units 315 1 0.25 0.75 79 236 315

Table 2: Proposed Development Total Trip Generation – Wednesday PM Peak Hour

No Extension Land Use Extent (units)

Trip Generation

Rate

Directional Split Trips Generated

In Out In (vph)

Out (vph)

Total (vph)

1 Irene Ridge Residential Units 315 1 0.7 0.3 221 95 315


CAPACITY ANALYSES RESULTS – SUMMARY Table 2: Summary of Capacity Analyses Results

Intersection / Approach

2017 Existing Traffic Volumes 2017 Existing Traffic Volumes including Development Traffic

Sc 1a: AM PEAK HOUR Sc 1b: PM PEAK HOUR Sc 2a:AM PEAK HOUR Sc 2b: PM PEAK HOUR V

/C

Del

ay

(sec

)

LOS

V/C

Del

ay

(sec

)

LOS

V/C

Del

ay

(sec

)

LOS

V/C

Del

ay

(sec

)

LOS

M57

/Ste

rkfo

ntei

n A

venu

e

NB 0.03 8.50 A 0.04 8.50 A 0.03 8.70 A 0.04 8.70 A

WB 0.05 18.50 C 0.08 21.40 C 0.05 22.60 C 0.11 19.80 C

SB - - - - - - - - - - - -

EB - - - - - - - - - - - -

Overall 0.04 13.30 C 0.08 16.70 C 0.05 14.60 B 0.11 19.80 C

M57

/Acc

ess

Roa

d NB 0.35 47.00 B 0.29 36.00 B 0.66 33.70 C 0.45 12.50 B

WB 0.04 36.20 D 0.30 51.70 D 0.02 29.80 C 0.07 27.80 C

SB 0.35 5.60 A 0.29 2.10 A 0.38 6.40 A 0.36 7.50 A

EB 0.35 42.20 D 0.33 53.00 D 0.66 44.50 D 0.45 34.10 C

Overall 0.34 7.10 A 0.33 5.20 A 0.44 22.90 C 0.45 14.40 B

M57

/24t

h St

reet

NB 0.01 8.40 A 0.00 8.20 A 0.01 8.70 A 0.00 8.50 A

WB 0.07 19.30 C 0.10 19.90 C 0.09 22.70 C 0.12 23.60 C

SB 0.01 8.00 A 0.00 8.30 A 0.01 8.10 A 0.00 8.40 A

EB 0.02 12.00 B 0.02 17.60 C 0.02 12.70 B 0.02 20.00 C

Overall 0.07 19.30 C 0.10 19.90 C 0.09 22.70 C 0.12 23.60 C

Hill

yfie

ld/T

raffi

c C

ircle

NB 0.02 3.00 A 0.03 3.10 A 0.02 3.20 A 0.03 3.20 A

WB - - - - - - 0.07 3.30 A 0.07 3.30 A

SB - - - - - - - - - - - -

EB 0.06 3.20 A 0.03 3.10 A 0.25 4.00 A 0.22 3.90 A

Overall 0.02 3.10 A 0.03 3.10 A 0.07 3.80 A 0.07 3.70 A


Intersection / Approach

2022 Background Traffic Volumes 2022 Background Traffic Volumes including Development Traffic

Sc 3a: AM PEAK HOUR Sc 3b: PM PEAK HOUR Sc 4a:AM PEAK HOUR Sc 4b: PM PEAK HOUR

V/C

Del

ay

(sec

)

LOS

V/C

Del

ay

(sec

)

LOS

V/C

Del

ay

(sec

)

LOS

V/C

Del

ay

(sec

)

LOS

M57

/Ste

rkfo

ntei

n A

venu

e

NB 0.01 8.50 A 0.04 9.10 A 0.04 9.60 A 0.05 9.70 A

WB 0.13 22.20 C 0.13 22.30 C 0.07 31.30 D 0.17 28.10 D

SB - - - - - - - - - - - -

EB - - - - - - - - - - - -

Overall 0.13 22.20 C 0.13 22.30 C 0.07 19.10 C 0.17 28.10 D

M57

/Acc

ess

Roa

d NB 0.66 32.00 C 0.47 11.90 B 0.54 23.60 C 0.60 20.50 C

WB 0.03 33.90 C 0.16 38.70 D 0.02 28.50 C 0.12 34.60 C

SB 0.38 4.60 A 0.33 4.80 A 0.42 8.80 A 0.41 8.70 A

EB 0.66 53.90 D 0.47 46.60 D 0.54 37.80 D 0.60 46.70 D

Overall 0.43 19.60 B 0.47 11.10 B 0.54 17.30 B 0.60 16.40 B

M57

/24t

h St

reet

NB 0.00 8.60 A 0.00 8.50 A 0.01 8.70 A 0.00 8.60 A

WB 0.03 13.10 B 0.15 26.30 D 0.13 30.30 D 0.18 31.90 D

SB 0.01 8.30 A 0.00 8.70 A 0.01 8.60 A 0.00 9.00 A

EB 0.09 25.40 D 0.02 21.90 C 0.03 15.10 C 0.03 25.50 D

Overall 0.09 25.40 D 0.15 26.30 D 0.13 30.30 D 0.18 31.90 D

Hill

yfie

ld/T

raffi

c C

ircle

NB 0.02 3.20 A 0.04 3.50 A 0.02 3.80 A 0.04 3.90 A

WB 0.19 3.70 A 0.19 3.70 A 0.38 5.00 A 0.37 4.90 A

SB - - - - - - - - - - - -

EB 0.14 3.50 A 0.11 3.40 A 0.22 3.80 A 0.19 3.70 A

Overall 0.19 3.60 A 0.19 3.60 A 0.38 4.50 A 0.37 4.40 A

traffic impact study: doornvallei...

Documents