Notes for Figure 6H-31 —Typical Application 31 Lane Closure on a Street with Uneven Directional Volumes
1. The illustrated information shall be used only when the vehicular traffic volume indicates that two lanes of vehicular traffic shall be maintained in the direction of travel for which one lane is closed.
2. The procedure may be used during a peak period of vehicular traffic and then changed to provide two lanes in the other direction for the other peak.
- For high speeds, a LEFT LANE CLOSED XX FT sign should be added for vehicular traffic approaching the lane closure, as shown in Figure 6H-32 6H-32(CA).
- Conflicting pavement markings should be removed for long-term projects. For short-term and intermediate-term projects where this is not practical, the channelizing devices in the area where the pavement markings conflict should be placed at a maximum spacing of 1/2 S feet where S is the speed in mph. Temporary markings should be installed where needed.The spacing of channelizing devices should not exceed the maximum distances shown in Table 6F-101(CA). Refer to Section 6F.63 for spacing of channelizing devices
- If the lane shift has curves with recommended speeds of 30 mph or less, Reverse Turn signs should be used.
- Where the shifted section is long, a Reverse Curve sign should be used to show the initial shift and a second sign should be used to show the return to the normal alignment.
- If the tangent distance along the temporary diversion is less than 600 feet, the Double Reverse Curve sign should be used at the location of the first Two Lane Reverse Curve sign. The second Two Lane Reverse Curve sign should be omitted.Use the Reverse Curve (W1-4) signs for both locations instead of the Double Reverse Curve or Two Lane Reverse Curve signs.
8. The number of lanes illustrated on the Reverse Curve or Double Reverse Curve signs shall be the same as the number of through lanes available to road users, and the direction of the reverse curves shall be appropriately illustrated. Curve warning signs with multiple arrows shall not be used in California. Only W1-3, W1-4, and W24-1 signs shall be used.
- A longitudinal buffer space may be used in the activity area to separate opposing vehicular traffic.
Where two or more lanes are being shifted, a W1-4 (or W1-3) sign with an ALL LANES (W24-1cP) plaque (see Figure 6F-4) may be used instead of a sign that illustrates the number of lanes.
- Where more than three lanes are being shifted, the Reverse Curve (or Turn) sign may be rectangular.
- A work vehicle or a shadow vehicle may be equipped with a truck-mounted attenuator.
When recommended speeds are the same for each curve, one Double Reverse Curve (W24-1) sign may be used, instead of two Reverse Curve (W1-4) signs, in advance of the first curve.