Section 3: Lane Closure Requirements

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Section 3: LANE CLOSURE REQUIREMENTS

3.1 Closing a Lane

The Contractor must properly plan, use, place and maintain traffic control devices while in use at the construction site. In general, blocking a traffic lane requires the use of a flashing arrow board. Solar flashing arrow boards are required in residential areas, especially at night, to minimize noise problems. In certain lane closures, the use of high-level warning flags along with other devices is acceptable if installed in accordance with the provisions set forth in the California MUTCD issued by the California Department of Transportation. Typical lane closure plans are presented in Appendix E.

3.2 Traffic Lane Requirements

The Contractor shall provide the required number of through traffic lanes according to the table and corresponding notes below.

Traffic Lane Requirements Per Direction (see note A)

Existing No. of Through Traffic Lanes	Minimum No. of Through Traffic Lanes To Remain Open (see notes B,C,D & G)
1	1 (note E)
2	1 (note F)
3	2
4	2
5	3
6	4

Notes:

A. For two-way streets, Contractor shall consider each direction separately. For example, a four-lane roadway with two lanes in each direction shall provide a minimum of one lane in each direction.

B. The minimum width of a traffic lane is 10 feet, clear of any obstructions, including traffic cones or delineators.

C. In addition to maintaining the required number of through lanes per the above table, Contractor shall provide a separate left (or right) turn lane if there is an existing left (or right) turn lane.

D. Contractor is responsible for ensuring that the lanes provided allow Muni trolley coaches to reach the overhead wires at all times (see Section 8.2 for further details).

E. Completely closing any direction of traffic is generally not allowed. This includes any plan which allows one lane to be used for two directions of traffic (“Two-Way Flag Control”). A STP is required to use “Two-Way Flag Control.”

F. If work occurs at or within 100 feet of a two way street intersection, the Contractor shall request a STP to prohibit left turns at the intersection. This applies where two lanes are reduced to one, resulting in a situation where through vehicles cannot physically pass a left-turning vehicle.

G. The complete closure of a roadway is not permitted without a valid Special Traffic Permit or as part of a DPT approved traffic routing plan.

3.3 Temporary Traffic Lanes

Room for a traffic lane(s) may be made available by temporarily prohibiting parking. Traffic lanes must be at least 10 feet wide and provide enough transition before the lane begins and after the lane ends.

3.4 Flag Control

Flaggers may be required by Contract specifications or a STP. Flaggers are also required where workers or equipment temporarily block a traffic lane in and out of a construction area.

The following rules apply to flaggers:

A. Flaggers must be properly equipped with an orange vest and a sign paddle.

B. Flaggers must be certified and must have their certification card at all times.

C. When a STP or Contract Specification allows the use of one lane for two directions of traffic (i.e., two-way traffic control), a minimum of two flaggers are required.

D. Police Officers may be hired to provide flag control (see Section 10 for further details).

3.5 Coordination with Others

In order to ensure that the traffic lanes provided are adequate and continuous, only one Contractor at a time is allowed to work on any one block. If a second contractor is planning to work on that block or on an adjacent block, then the second contractor shall obtain a STP before starting any work. Moreover, a Contractor is not allowed to work within a block of a project under City Contract without the approval of the Resident Engineer of the subject contract, and a STP.

Alley Closures for One-Way Alleys (Diagram Appears Below)
This plan shows how to change a one-way alley into a temporary two-way alley

Notes:
1. Special Traffic Permits are required for all alley and street closures
2. Maintain local access at all times
3. Sidewalks should remain open to pedestrians
4. A flag-person should be posted at each end of the block
5. For two-way alleys, W6-3 signs are not required.

Alley Closures for One-Way Alleys

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