Lighting to be installed with the general construction of a highway is not incidental to such construction and is listed in the "Type of Improvement" on the construction program in accordance with 121 Project Planning, Prioritization and STIP Commitments. It is eliminated at the design stage if not warranted for installation at the time of completion of the general construction. Lighting on an existing intersection, interchange or roadway is programmed approximately three years prior to installation.
The district authorizes lighting design when justified by MoDOT policy as stated in 901.2, 901.3 and 901.4. The district documents the warrant forms and traffic data for each installation, that is, for each interchange and each intersection where basic lighting is proposed or for each project if continuous lighting is proposed.
The following guidelines are for state installed, operated and maintained lighting facilities. Lighting facilities installed by permit from Traffic may incorporate variations due to selection of equipment and location.
901.6.2 Warrant Form D-21
Form D-21 is to be completed for each installation. On this form, the Sections 1. Conditions, 2. Proposed Design, and 3. Costs are largely based on MoDOT policy as outlined in Highway Lighting. When the Conditions justify the Proposed Design, additional warrants are not required. Section 4, AADT at Time of Completion, applies to only freeways and interchanges. The construction year AADT is obtained from the Transportation Planning Division. When continuous freeway lighting is proposed, only the volume on the freeway through-lanes is shown since continuous freeway lighting includes interchanges. The volumes on crossroad through-traffic lanes and off-ramp traffic are also shown when interchange lighting alone is proposed. The volume for through-traffic lanes on a freeway or crossroad is the total volume proceeding straight through an interchange in opposite directions. One of these would be N to S plus S to N, the other E to W plus W to E. The sum of all other movements would be the ramp traffic entering and leaving the freeway.
901.6.3 Form HP-770
The current AADT, the construction year AADT, the percent truck traffic, and the peak hour traffic are included on Form HP-770. This information is obtained from Transportation Planning on request. Estimates of traffic for short sections of a roadway facility are unreliable, as they are not correct when additional sections are added. Therefore, estimates are based on a completed facility.