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P106654
LION’S HILL RESIDENTIAL DEVELOPMENT
QUARRY HILL ROAD, TAMBOERSKLOOF
TRAFFIC IMPACT STATEMENT
NOVEMBER 2010
Prepared by: Prepared for:
Aurecon SA (Pty) Ltd. Aurecon Centre, Century Falls, Century Boulevard, Century City P O Box 494, CAPE TOWN, 8000 Tel : (021) 526 9400 Fax : (021) 526 6500
Lion’s Hill Development Company
2nd floor Sunclare Building 21 Dreyer Street, Claremont
Lion’s Hill, Tamboerskloof – Traffic Impact Statement
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1. INTRODUCTION
This traffic impact statement has been prepared by Aurecon SA (Pty) Ltd on behalf of
Lion’s Hill Development Company (Pty) Ltd in support of the development application for
erf 1526, Tamboerskloof. The project site is referred to as Lion’s Hill and is located
between Quarry Hill Road and De Hoop Avenue in Tamboerskloof. It is proposed that
the presently vacant land be developed to accommodate 1171 residential units of various
sizes. The development will cater for middle and high income tenants.
2. DEVELOPMENT LOCATION
The site, located in Tamboerskloof, is accessible from Quarry Hill Road and De Hoop
Avenue as shown in Figures 1 and 2. These are both local roads accommodating
two-way traffic and some undemarcated on-street parking.
Quarry Hill Road is a cul-de-sac, terminating in the entrance to an existing residential
development and will provide entrance to the site at two points. The two entrances will
serve 6 and 111 units respectively. The former will provide entrance and egress for the
six units. The latter entrance, providing entrance only, will be at the end of Quarry Hill
Road, opposite the existing turning embayment. Egress from the site for the 111 units
will be into De Hoop Avenue.
De Hoop Avenue is linked at one end into Quarry Hill Road, turning off close to Kloof
Nek Road. At the other end, De Hoop Avenue becomes Upper Albert Road, in a sharp
bend. The egress for the 111 units will be from the site onto De Hoop Avenue about
100 metres from the Upper Albert Road corner.
De Hoop Avenue provides extensive linkage to the local road network, allowing a variety
of choices with respect to entering onto Kloof Nek Road. This is discussed later.
3. DEVELOPMENT PROPOSAL
The development proposal is for the construction of 117 residential units in a multi-
structure, complex. The development is structured in such a manner as to create three
main segments and incorporates three separate parking areas. One provides for the
6 units whilst the other two each provide for 44 and 67 of the remaining residential units
respectively.
1 The development is such that it is possible to merge or split some units. It is thus possible that the final project will have one or two fewer but large units or more, but smaller units.
2 Figure 1: Lion’s Hill site and local street network .
3 Figure 2: Aerial view of site and local street netw ork.
Lion’s Hill, Tamboerskloof – Traffic Impact Statement
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The distribution of the units and required parking on the site is as shown in Table 1.
Table 1: Number and distribution of residential uni ts and required parking bays on
development site.
Block Location 3-Bed 2-Bed 1-Bed Total Bays
Quarry Hill (Small) 6 - - 6 12
Quarry Hill (Main) 8 24 12 44 88
De Hoop 12 39 16 67 134
Total 26 63 28 117 234
4. ON-SITE PARKING
The site is zoned R5 with a parking requirement of 1 bay per unit inclusive of visitors
parking and a visitors parking requirement of 1 bay per 4 units, i.e. a parking requirement
of 0.75 bays per apartment and 0.25 visitors bays per apartment.
Notwithstanding the above, the site allows for the City of Cape Town recommendations
for parking, 1.75 bay per unit plus 0.25 bays per unit for visitor parking; i.e. 2 bays per
unit, giving 234 parking bays. The site will incorporate a total of 237 parking bays and
thus exceeds the minimum requirement irrespective of the determination method.
These bays are apportioned directly to the units linked to each access as shown Table 1
with 3 additional bays.
5. INTERNAL CIRCULATION AND SITE ACCESS
The site is on a slope that runs down from Quarry Hill Road to De Hoop Avenue. In
order accommodate the topography, two separate access points are provided on Quarry
Hill Road, each linking to a small surface parking area at the entrance to under-building
parking for each main block.
The main Quarry Hill Road access will be at the end of Quarry Hill Road, in the turning
area in which Quarry Hill Road terminates. This entrance follows a natural contour at
the link to Quarry Hill Road and so appropriate slopes are achieved at the entrance.
This entrance serves 111 units and enters the road network at a point where there is no
passing traffic other than that from the adjacent property entrance.
The secondary entrance on Quarry Hill Road will be approximately 90m west of the
above entrance. This entrance is not ideally located, being on both a bend and a slope.
Lion’s Hill, Tamboerskloof – Traffic Impact Statement
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It is does however, more or less follow a contour line, allowing reasonable transition
profiles. Serving only 6 residential units and being along a cul-de-sac with only limited
development along its remaining length, the traffic volumes and speeds are such that
the access position should not represent safety problems provided that the detail design
for the entrance ensures adequate sight distance.
The De Hoop Avenue egress is about 100m from the point at which De Hoop Avenue
turns down into Upper Albert Road. De Hoop Avenue in this area is relatively flat and
sight distances are good. However, the development site has a relatively steep slope at
this point, requiring some cutting to achieve the appropriate transition profiles. These
will be detailed on the engineer’s drawings.
Refuse and emergency vehicles can be accommodated along both Quarry Hill Road and
De Hoop Avenue and an embayment for refuse vehicles is to be provided adjacent to
the De Hoop Avenue exit. Emergency vehicles will be able to access the site by means
of the through way, stopping in the visitor parking areas.
6. TRIP GENERATION AND DISTRIBUTION
The development will be in the form of apartments or flats and is expected to attract
medium to high-income residents. In terms of the National Department of Transport
“Trip Generation Rates” 2nd edition, a peak-hour trip generation rate of between 1.1 and
1.5 vehicle trips per residential unit may be expected. Many of the units are one-
bedroom apartments and it is thus suggested that the generated trips will not exceed
that shown in Table 2.
Table 2: Trip Generation based on Unit Type.
Unit Type Quantity Trip Rate Trips
1-Bed 28 1.1 31 2-Bed 63 1.5 95
3-Bed 26 1.5 39
117 165
The result of the above is an anticipated 165 peak hour vehicle trips, with a 75:25 Out-In
split in the morning and the reverse in the evening. These trips will distribute onto the
network in accordance with the permitted movement through the site, giving rise to a trip
pattern as shown in Table 3.
Table 3: Projected vehicle trip patterns.
AM In AM Out PM In PM Out Quarry Hill (Small) 3 7 7 3
Lion’s Hill, Tamboerskloof – Traffic Impact Statement
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Quarry Hill (Main) 40 116 De Hoop Avenue 116 40
Sub Totals 43 123 123 43 TOTAL 166 166
Note: The 1 trip discrepancy in the total reflected in the table from that in the text is due to rounding up of all numbers in splitting trips between access points.
In terms of the Provincial Administration of the Western Cape Road Access Guidelines of
2002, a development of this size requires only a traffic impact statement. A slightly
different interpretation may be obtained from the National Department of Transport
Manual for Traffic Impact Studies; PR 93/635 which recommends a traffic impact study at
150 peak-hour trips. However, the local traffic volumes are low and given the local road
network structure and access locations, the vehicular movement at the site entrances is
expected to have negligible impact on existing traffic and will not be impeded in any
meaningful way by existing local traffic. It is thus argued that a traffic impact statement
should suffice in this case. Furthermore, the site is located close to a number of schools,
two of which are within the same local area as a result of which the projected trip
generation rates are believed to be an over-estimate, children being able to walk to local
schools.
Trips that leave the immediate area are expected to be to and from the City Centre or
across Kloof Nek Road towards the Gardens area. The one potential concern relating to
vehicular traffic generated by this site thus relates to access to and from Kloof Nek Road.
Kloof Nek Road is on a significant incline and supports a relatively high and continuous
level of traffic. The road is not however subject to extreme congestion, with only limited
congestion during the peak periods. Of particular note is that Quarry Hill Road, and thus
one end of De Hoop Avenue, has its access onto Kloof Nek Road on a bend on a slope.
At this intersection however, Kloof Nek Road has a dedicated left turn lane whilst one of
the two lanes in the other direction provides a de facto right turn lane. Regular
observations of this intersection are that the number of vehicles waiting to turn right from
Kloof Nek Road into Quarry Hill Road rarely exceeds one and that although it would be
feasible to formalise a right turn lane, the impact on the free flow of Kloof Nek Road is
not considered justified.
In mitigation of concerns regarding access from and onto Kloof Nek Road, it is noted that
the development site has good access through the local road network, with as many as
13 separate intersections offering access from or onto the broader network, thus allowing
distribution of the traffic over a wide area. One of these, Burnside Road, joins Kloof Nek
Road at a signalised intersection. On this basis, it has not been considered warranted to
undertake a detailed analysis of any of the intersections. In support of this decision,
Lion’s Hill, Tamboerskloof – Traffic Impact Statement
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frequent but unquantified peak hour observations of local traffic are that, during both
morning and evening peaks, in spite of overall traffic levels and the apparently awkward
movements owing to road alignments, there is rarely a queue development of more than
two or three cars at any of the intersections, either onto of from Kloof Nek Road. The
operation of Kloof Nek Road is generally such as to permit vehicles to enter and leave
side roads with only limited delay. Given the potential for broad distribution of the traffic,
the additional traffic generated by the site is not anticipated to have a measurable impact
on the performance of any of the local intersections or the local road network..
7. CONCLUSION AND RECOMMENDATION
It is concluded that the peak-hour vehicular trip generation will have negligible impact on
the local transport network, there being sufficient diversity of access opportunity such as
will minimise traffic movements at intersections with high levels of conflict, or onto
significantly congested roads.
It is further concluded that the development proposal makes adequate allowance for on-
site parking. However, although the on-site parking provision meets with the City of
Cape Town’s recommendations and is believed to be sufficient for the development, the
developers should ensure the proper allocation and management of parking during the
sale or letting of the residential units.
Provision is made for a refuse vehicle embayment on De Hoop Avenue thus avoiding the
need for regular incursion of large vehicles onto the site, the topography of which is
unsuited to such vehicles. In this regard, it is recommended that detailed development
planning makes appropriate provision for the storage of refuse adjacent to the refuse
vehicle embayment.
In terms of the access and egress points, particularly the minor Quarry Road entrance
and the De Hoop Avenue exit, it is recommended that the detailed engineer’s drawings
for the site access points clearly indicate achievement of adequate sight distances from
the access stop lines.
In conclusion, it is recommended that the development application not be disallowed on
the basis of parking provision or traffic factors.
WAYNE DUFF-RIDDELL Pr.Eng. PhD. Technical Director – Transportation Planning.