(h) Depending upon the size of the project,
(b) Location away from any elements (e.g.,
marginal or medial channelization.
building, topography or vegetation) which block or
(i) Adequate throat width and length to
lessen sight distance.
channel vehicles into the proper lanes, discourage
(c) Adequate views and signage of entry to
erratic movement and provide storage space on the
the site from the access road.
access drive. This prevents vehicles which have
(d) Use of topography, vegetation and water
slowed or stopped from blocking the path of vehi-
to reinforce a sense of entry.
cles entering the site.
(e) Maintenance of maximum spacing be-
(2) Access Drives. Normally, traffic enters and
tween access drives occurring on the same access
exits the site at the same access point or points,
but not all vehicles have the same purpose or
(f) Alignment of access drives which occur
destination. Figure 4-6 illustrates a typical circu-
across the access road from each other. If this is
lation flow diagram. Understanding traffic flow
not possible, a separation of 75' between access
and patterns on site helps determine the location
drives is generally adequate.
of turn-around areas, appropriate turning radii at
intersections and appropriate drive widths. Differ-
(g) Right-angle turns from the access road
ent drive widths can be used for different types of
onto the access drive.
Figure 4-6. Typical Circulation Flow Diagram.