4895_RAL20-0020Response

RAL20/0020 Reconfiguration of a Lot: Response to Information Request – Report                           12


Assuming a critical gap acceptance time of 5s for both left and right turns from the driveway,
the minimum gap sight distance (MGSD) at 80km/hr is 111m; sight distance approximately
complies.
Sight distance to the West is therefore non-compliant for inbound cars and trucks. Sight
distance to the East for all outbound traffic complies.

4.1.2.4.2 Existing driveway formation in the road reserve
The existing driveway to Lot 49 comprises a broadly formed and gravelled crossover, at-grade
with the verge, followed by a gravelled access that ramps up approximately 90m along the top
of road embankment to reach the existing property boundary of Lot 49.
The formation at the road shoulder is approximately 16m; the gravelled ramp formation is an
average of 2.8m, being constrained between embankment and property boundary.
There is no table drain to carry under the crossover as the road cambers to the opposite side;
the limited runoff from the embankment catchment is assumed to sheet-flow across the road.
The ramp crossfalls away from the embankment, toward a small table drain on the boundary.
There is no fall away from the road shoulder to create a low point – the area adjacent the
shoulder has a slight fall (<1%) toward the property boundary.
The standard of pavement is similar to a Class ‘U3’ unsealed road per Table 2.1 of the
Austroads Guide to Pavement Technology Part 6: Unsealed Pavements:

    •   Natural gravels, pit materials or quarry wastes;
    •   40 mm max. size wearing course, min. 100 mm thick;
    •   55 mm max. size subbase, min. 150 mm thick.




Figure 8: Lot 49 Property Access: road reserve crossover as viewed from road, outbound lane.

4.1.2.4.3 Required safety improvements
Improvements to the crossover are proposed to be incorporated in its redesign as a shared
property access with the new Lot 429. The changes will increase the level of safety for the
property owner of Lot 49 and road users, particularly considering the sight distance limitations
to traffic in the inbound direction
Modifications will include the to the following recommendations to improve safety:




                                                                                               Long View
                                                                                               Consulting Engineers