Streetlight Design Manual

General Purpose of the Design Manual:

This Streetlight Design Manual has been written to serve as a general guideline when designing a streetlighting system for the City of Overland Park, Kansas. Although there are specific design requirements, the guidelines contained herein should not be a substitute for proper engineering design and judgment based on specific project situations. The purpose of this Streetlight Design Manual is to aid consultants as well as City of Overland Park staff to be consistent in the practice of designing streetlighting plans. It provides an overview of what tasks are expected to be included in the scope of the design; what information should be included on the plan sheets; what kind of backup design information is required for proper analysis; and what is expected for the final deliverable product. Any questions regarding this manual may be directed to Bruce Wacker, P.E., Assistant City Traffic Engineer at the City of Overland Park, Kansas at (913) 895-6027 or by email at [email protected].

Purpose of Streetlighting:

The principal purpose of lighting is to provide improved visibility for the street users so they can make quick, accurate and safe decisions. Street users include vehicle operators, bicycle and motorcycle operators and pedestrians. Light that falls on pedestrian walkways enhances pedestrian traffic, but the streetlighting criterion does not mandate specific lighting levels on sidewalks, bike paths or other pedestrian paths. The Planning and Development Services Department has separate criteria for the lighting of pedestrian facilities and should be consulted. This document does however, mandate specific lighting levels at the conflict points of pedestrians and vehicles, such as at intersection crossing points.

Reference to Other Documents:

Wherever applicable, this design manual should be used in conjunction with the American National Standard Practice for Roadway Lighting Illuminating Engineering Society of North America, RP-8-14, as herein modified and the National Electric Code by the National Fire Protection Association. The current editions of the City of Overland Park Streetlighting Resolution, Design and Construction Standards, Volume 1 Design Criteria (latest edition), Technical Streetlighting Construction Specifications, Standard Details and the Approved Materials List, hereafter referred to as “City Standards” should be followed during the design of any streetlighting project.

Public or Private Ownership, Operation and Maintenance:

Different policies apply to streetlighting systems based on the final ownership, operation and maintenance of the system. The two types of systems are 1) those that are installed in the public right-of-way that will be owned, operated and maintained by the City of Overland Park and 2) privately owned streetlighting systems that are installed in the public right-of-way that will not be owned, operated and maintained by the City of Overland Park. Although each of the systems will be discussed, the design guidelines contained herein only apply to systems that are within the public right-of-way that are owned, operated and maintained by the City of Overland Park.

     City-Owned, Operated and Maintained Lighting Systems:

All City-owned, operated and maintained lighting systems shall be designed in accordance with the design criteria listed herein and use all pre-approved materials from the City’s Approved Materials List, which is available at City Hall or from the City’s web page http://www.opkansas.org/doing-business/civil-engineering/approved-materials-list/. All lighting systems that are being designed in conjunction with the development of any public street or any developments that require modification of any streetlighting system within the public right-of-way by private consultants working for a developer are required to meet City Standards if the City will assume all ownership, operation and maintenance responsibilities after final acceptance of the project.

     Privately Owned, Operated and Maintained Lighting Systems:

All lighting systems within the public right-of-way that have been designated “privately owned” are not required to be constructed using City approved materials. However, the lighting system shall still be designed in accordance with the design criteria listed herein for average maintained light levels and uniformity ratios for the specific functional roadway classification and pedestrian conflict area classification and be constructed in accordance with the National Electric Code, current edition to ensure safe operation.

All proposals for privately owned, operated and maintained lighting systems shall be pre-approved by the Overland Park City Council prior to final plan approval and execution and recording of the City standard maintenance agreement with the Johnson County Records and Tax Administration. If at any time, the homes association or other political subdivision requests the City to assume ownership of the lighting system, the streetlighting maintenance agreement establishes specific items that would need to be addressed before the request would be considered. One requirement is that the current streetlighting system would be have to be replaced with equipment meeting the current City Standards at the sole cost of the current owner.

Privately owned streetlighting systems shall not be permitted to connect to any City-owned streetlighting system, whether it is poles, control centers, cable, junction boxes, etc. unless otherwise stipulated in the maintenance agreement.

Design Criteria:

The following section addresses the design criteria used for streetlighting in the City of Overland Park depending on the various types of lighting being considered. There are two types of streetlighting design used within the City of Overland Park: 1) Continuous lighting and 2) Safety lighting. Continuous streetlighting is required for all collector and thoroughfare designated streets. Safety lighting should be used for residential designated streets. There are specific lighting criteria for each of the two types that will be discussed.

Continuous Lighting:

Continuous lighting is defined as streetlighting that is designed to provide specific average maintained light levels and uniformity ratios between adjacent poles in accordance with the functional classification of the street and the corresponding pedestrian conflict area classification. Continuous lighting design shall be required for all collector and thoroughfare street classifications.

The following streetlighting design criteria will be used for all thoroughfare streets and collector streets, whether improved or unimproved, regardless of the number of through travel lanes and auxiliary lanes, as identified on the latest edition of the City of Overland Park “Official Street Map”, and the “Future Development Master Plan” available from the Planning and Development Services Department.

     Functional Street Classifications:

The “major” street classification includes all thoroughfare streets whether divided or undivided; whether improved or unimproved; and whether two-lane, four-lane or six-lane excluding auxiliary left and right turn lanes.

The “collector” street classification includes all super-collector, residential collector streets, apartment streets, commercial streets and industrial streets regardless of the number of lanes; whether improved or unimproved.

     Pedestrian Conflict Area:

The “high” pedestrian conflict area includes areas where significant numbers of pedestrians are expected to be on the sidewalks or crossing the streets during darkness. These are typically areas that are in the “Nonresidential Category” zoned for “commercial” or “mixed-use” such as retail areas, near theaters, or major pedestrian generators.

The “medium” pedestrian conflict area includes areas such as libraries, apartments, neighborhood shopping and schools which would be considered in the “Nonresidential Category” and zoned as either “public and semipublic” or in the “Residential Category” that would be zoned as either “high-density” or “medium-high density”.

The “low” pedestrian conflict area includes areas in the “Residential Category” zoned as “medium-density” or “low-density” such as single family residential housing or duplexes.

     Luminance Criteria:

The maintained averages for luminance, as listed in Table 1, shall be met or exceeded for all continuous lighting designs. The corresponding uniformity ratios and/or veiling luminance ratios shall be equal to or better than those listed in the following table for luminance.

Table 1: Luminance Criteria

Street and Pedestrian Conflict Area		Luminance Criteria
Functional Street Classification	Pedestrian Conflict Area	Maintained Average (Lavg) (cd/m2)	Uniformity Ratio (Lavg:Lmin) (Max Allowable)	Uniformity Ratio (Lmax:Lmin) (Max Allowable)	Veiling Luminance Ratio (LVmax:Lavg) (Max Allowable)
Thoroughfare	High	1.2	3.0:1	5.0:1	0.3:1
	Medium	0.9	3.0:1	5.0:1	0.3:1
	Low	0.6	3.5:1	6.0:1	0.3:1
Collector	High	0.8	3.0:1	5.0:1	0.4:1
	Medium	0.6	3.5:1	6.0:1	0.4:1
	Low	0.4	4.0:1	8.0:1	0.4:1

Safety Lighting:

Safety lighting is defined as lighting that does not provide specific maintained light averages and uniformity ratios between adjacent poles in accordance with the functional classification of the street and corresponding pedestrian conflict area classification. The purpose of this type of lighting design is to provide enough light on the street to enhance the safety of the street users but to avoid over lighting the area. All residential streets shall be designed based on the safety lighting design parameters.

Since June 11, 1979, the City policy has been not to continuously light residential streets. Only" partial" or "safety" lighting is provided. All street lights on residential streets will be installed in conformance with the following basic guidelines.

     At Intersections with Other Residential Streets:

In order to provide lighting within the conflict area of two residential streets, a light pole will be installed on one corner of an intersection or opposite the intersection in the case of a T-intersection. (See Figure 1)

     On the Same Side as the Sidewalk:

Streetlights should generally be installed on the same side of the street as the sidewalk unless there are significant utility or storm sewer conflicts. Any variance from this practice should be approved by the engineer or project manager.

     Near Intersections with Another Pole Oriented in a Different Direction:

Where an intersection has a light pole located at the corner but the luminaire is oriented toward the direction of the primary local street, a second light pole may be located on the secondary local street oriented in the direction of its centerline as long as the light pole is installed greater than 50’ from the back of curb line on the primary local street extended, and it is not on the same corner as the light oriented toward the primary street. (See Figure 1)

     Within Cul-de-Sac Bulbs:

A light pole will be installed within the cul de sac bulb when the cul-de-sac street is longer than 200 feet measured from the intersection of the intersecting streets to the center of the cul-de-sac bulb. (See Figure 2)

     At Changes of Roadway Alignment:

A light pole will be installed at changes of alignment of 60 or more which are 200 feet or more from an intersection, measured from the intersection of the local street centerlines, to the middle of the curve radius along the centerline of the local street, (See Figure 3)

     Mid-block Street Lights:

A minimum number of mid block street lights will be installed in order to achieve a desired pole spacing of approximately 250 feet. The maximum spacing between lights should not exceed 280 feet and the minimum spacing between lights should not be less than 225 feet unless otherwise approved by City staff. Lights should desirably be located on or near a property line and not in front of window lines if avoidable.

Intersection Lighting:

Intersections pose the highest conflict area for both vehicles and pedestrians. Therefore, the light levels should be higher for intersections than each individual street. The illuminance method, rather than the luminance method is the recommended design for intersection lighting. The following design criterion has been established for the illumination at street intersections.

Table 2: Illuminance Criteria for Intersections

Functional Street Classification	Average Maintained Illumination at Pavement by Pedestrian Area Classification, (Fc)			Uniformity Ratio (Eavg:Emin (Max Allowable)
	High	Medium	Low
Thoroughfare / Thoroughfare	34.0 / 3.4	26.0 / 2.6	18.0 / 1.8	3.0:1
Thoroughfare / Collector	29.0 / 2.9	22.0 / 2.2	15.0 / 1.5	3.0:1
Thoroughfare / Local	26.0 / 2.6	20.0 / 2.0	13.0 / 1.3	3.0:1
Collector / Collector	24.0 / 2.4	18.0 / 1.8	12.0 / 1.2	4.0:1
Collector / Local	21.0 / 2.1	16.0 / 1.6	10.0 / 1.0	4.0:1
*Local / Local	NA	NA	NA	NA

*Intersection lighting analysis is not required for local / local street intersections. The criterion is satisfied if a light is placed at each intersection.

The intersection lighting grid is defined as the quadrilateral whose adjacent sides intersect at the midpoint of the curb radii at the back of curb (See Figure 4). The amount of light should be proportional to the classification of the intersecting streets and be equivalent to the sum of the values used for each separate street. If an intersecting street is illuminated above the recommended value, then the intersection illumination value should be increased proportionately. Intersections of collector and thoroughfare streets with local streets should be illuminated according to Table 2 above since criteria has not been established for continuously lighting local streets.

Streetlighting Installation Determination:

The following information has been established for all City-owned and maintained streetlighting systems installed in public right-of-way. The following explains when streetlighting will be installed. Additional information is contained in Resolution No. 4036, A Resolution Establishing Policy for City-Owned Streetlighting, and the Overland Park Municipal Code, Chapter 13.10.

Local Residential Streets:

There are four main distinct scenarios identified in which street lights will be considered for installation. They are 1) streets with existing City-owned street lights, 2) streets that do not have any streetlighting, 3) streets that have streetlighting that was purchased from Kansas City Power and Light (KCP&L), and 4) new streets that are being constructed either through the City’s Capital Improvement Plan (CIP) or by developers.

     Residential Streets with Existing City-owned Streetlighting:

Where street plans were approved prior to February 7, 2011, the City will replace or modify the existing streetlighting system with a new streetlighting system meeting the current streetlighting resolution as the street(s) are reconstructed as part of a major residential street reconstruction program. This does not include general pavement rehabilitation programs such as micro-surfacing, chip seal or residential street overlay programs. The City will not consider requests or petitions to upgrade the existing streetlighting system to the current standards unless all other lighting obligations within the City have been met, including replacement of Kansas City Power and Light Company street lights the City has purchased and streets that currently do not have any streetlighting.

     Residential Streets with no Existing Streetlighting:

Where City streets do not have any existing streetlighting, the City will consider streetlighting using City at Large funds if a petition from over fifty (50) percent of the residences along the street(s) to be lighted is received and verified. Only one signature is allowed per residence on the petition. The City is responsible for receiving and verifying petitions which can be obtained from the Public Works Department. Verified, valid petitions will be listed for Public Works Committee consideration. The Public Works Committee in turn will make recommendations to the City Council for construction of local residential streetlighting consistent with the amount of funds budgeted for that purpose. When requests exceed funding, priority will be given to those local residential streets with the most police reports of nighttime crime and nighttime traffic accidents.

     Residential Streets with Existing KCP&L Streetlighting that was Purchased:

Where City streets have streetlighting that was purchased from Kansas City Power and Light Company, the City will annually prepare plans to remove existing streetlighting systems and replace them with current standard City-owned streetlighting systems as funding levels permit. The City staff will determine the street(s) that will be included in the annual streetlighting replacement project based on the streetlighting master plan. The project limits will be presented to the Public Works Committee for consideration. The Public Works Committee in turn will make recommendations to the City Council for final design and construction approval consistent with the amount of funds budgeted for that purpose.

     New Residential Streets

Where street plans were approved on or after February 7, 2011, the developers are required to install street lights on all local residential streets which have street plans approved in accordance with Ordinance Chapter 13.10.050. Appropriate City staff shall have authority in determining the extent and phasing of street light construction, including the location of any applicable street light control centers that best fit into the overall master plan for future expansion of lighting circuits.

Collector Streets:

There are three main distinct scenarios identified in which street lights will be considered for installation. They are 1) streets with existing City-owned street lights, 2) streets that have streetlighting that was purchased from Kansas City Power and Light (KCP&L), and 3) new streets that are being constructed either through the City’s Capital Improvement Plan (CIP) or by developers.

     Collector Streets with Existing KCP&L Streetlighting that was Purchased:

Where City streets have streetlighting that was purchased from Kansas City Power and Light Company, the City will annually prepare plans to remove existing streetlighting systems and replace them with current standard City-owned streetlighting systems as funding levels permit. The City staff will determine the street(s) that will be included in the annual streetlighting replacement project based on the streetlighting master plan. The project limits will be presented to the Public Works Committee for consideration. The Public Works Committee in turn will make recommendations to the City Council for final design and construction approval consistent with the amount of funds budgeted for that purpose.

     Collector Streets with Existing City-owned Streetlighting:

Where street plans were approved prior to February 7, 2011, the City staff may initiate streetlighting requests for these types of streets via the City's Capital Improvements Program (CIP) which is reviewed and updated annually. Approved collector streetlighting projects are normally listed in the Budget.

     New Collector Streets:

Where street plans were approved on or after February 7, 2011, developers are required to install street lights on all such types of streets which have street plans approved in accordance with Ordinance Chapter 13.10.050. Appropriate City staff shall have authority in determining the extent and phasing of street light construction, including the location of any applicable street light control centers that best fits into the overall master plan for future expansion of lighting circuits.

Thoroughfare Streets:

There are two main distinct scenarios identified in which street lights will be considered for installation. They are 1) new City-owned street lights, and 2) streets that have streetlighting that was purchased from Kansas City Power and Light (KCP&L).

     New Thoroughfare Streets:

The City staff may initiate thoroughfare streetlighting requests for this type of street via the City's Capital Improvement Program. Approved primary thoroughfare streetlighting projects are normally listed in the Budget.

     Thoroughfare Streets with Existing KCP&L Streetlighting that was Purchased:

Where City streets have streetlighting that was purchased from Kansas City Power and Light Company, the City will annually prepare plans to remove existing streetlighting systems and replace them with current standard City-owned streetlighting systems as funding levels permit. The City staff will determine the street(s) that will be included in the annual streetlighting replacement project based on the streetlighting master plan. The project limits will be presented to the Public Works Committee for consideration. The Public Works Committee in turn will make recommendations to the City Council for final design and construction approval consistent with the amount of funds budgeted for that purpose.

Design Considerations:

Before initiating the design of a streetlighting system, the designer should contact the City staff to discuss the specific design criteria for the project and determine the scope of the project. Decisions should be made in regard to the functional roadway classification and pedestrian conflict area as well as the type of equipment that will be used in the design. The following is a brief summary of general design considerations.

Establish the Lighting Design Criteria:

All streetlighting designs for collector and thoroughfare streets shall be done in accordance with the Continuous Streetlighting Design Criteria, as already discussed.

From the Design Criteria Table, select the row corresponding to the functional roadway classification (Major or Collector). Then select the row corresponding to the pedestrian conflict area (High, Medium or Low). Follow this row across the table to determine the maintained average luminance, average to minimum luminance uniformity ratio, maximum to minimum luminance uniformity ratio and veiling luminance ratio to be achieved in the design.

Before any design is initiated, the designer should discuss the functional roadway classification and the pedestrian conflict area classification with City staff. The pedestrian conflict area should be based on the City of Overland Park’s Future Development Master Plan and the functional roadway classification should be based on the City of Overland Park Official Street Map.

Design calculations, indicating the design pole spacing, should be submitted with supporting data to verify that the proper light levels have been achieved.

Light Loss Factor:

After the initial installation of the streetlighting system, the light output continues to decrease over time due to many external factors. The result of the time-dependent depreciation effects must be considered in the initial design. The lighting design is based on a specific lighting level that should always be maintained at the end of the maintenance period. Therefore, the initial lighting in the field will always be brighter than required.

The light loss factor (LLF) is a multiplying factor included in the calculations to account for factors which change in time after the initial installation of the streetlighting system. This factor is the product of many other individual factors such as the maintenance factor, lamp lumen depreciation, luminaire dirt depreciation, equipment factors, etc. The LLF is multiplied by the initial lumen rating of the light source to determine the number of maintained lumens in the design. The LLF that should be used for all high pressure sodium (HPS) City streetlighting systems is 0.81. The LLF that should be used for all LED City streetlighting systems is 0.91.

Luminaire Selection:

The luminaire selection should be based on the type of street as well as the ability to meet the lighting criteria and maximize the pole spacing. All luminaires used on collector streets and thoroughfare streets shall be LED cobrahead style as specified in the section “Approved Streetlighting Equipment”. All luminaires on residential streets shall still be high pressure sodium (HPS).

Luminaire for Residential Streets:

All luminaires on residential streets shall be a post top mounted fixture with a 100W HPS lamp. The luminaire shall be from the City’s Approved Products List.

Pole Locations:

Pole locations will vary depending on the type of street. Residential streets, collector streets in residential neighborhoods, collector streets in commercial areas, undivided thoroughfare streets, and divided thoroughfare streets will all have different design challenges. In addition to the pole location criteria already discussed for residential streets, there are additional pole location preferences that should be kept in mind. Each of the pole location preferences will be further discussed as follows.

4.4.1. Pole Location Preferences on Residential Streets: Sidewalks are generally only constructed on one side of residential streets. Since the street lights do provide some residual benefit of lighting the sidewalk and enhance pedestrian safety, the first choice for locating the street light poles should be on the sidewalk side of the street.

As long as there is a minimum of a 4’ grass parkway between the back of curb and the sidewalk, the poles should desirably be located in the grass parkway. The minimum distance from the back of curb to the center of the street light pole should be 3’. If a 3’ pole setback cannot be achieved, consideration should be made to move the sidewalk adjacent to the curb, at least near the vicinity of the pole, and locate the pole 1’ behind the sidewalk.

If street light poles cannot be located on the sidewalk side due to storm drainage, utility conflicts or right-of-way considerations, the poles may be moved to the other side of the street. The 3’ minimum setback from the back of curb to the center of the pole should still be maintained.

Poles located at the intersection of residential streets should desirably be placed so the light pole can be used to mount stop, yield and street name signs. That means that they should be installed as near to the location where a vehicle should stop while maintaining a minimum of 3’ setback from the back of curb.

All poles installed in residential areas should ideally be located on or near property lines whenever possible. In the case of larger lots, poles cannot always be located on the property line. In these cases, in order not to exceed the maximum desired pole spacing, poles can be located within the lot. The designer should take care not to locate the pole in front of large windows of houses.

Any pole located near a residential drive entrance should be located a minimum of 3’ from the edge of the drive or concrete wing. The designer should always be careful not to mount a pole in a location that could be in the path of an errant vehicle that may be backing out of the driveway. An example would be on a curved drive entrance.

The designer should also coordinate the location of all poles with existing trees, such that the fixture does not extend into the tree canopy or such that the tree canopy does not block the light output from the fixture.

4.4.2. Pole Location Preferences on Collector Streets: Collector streets generally have sidewalks on both sides of the street and are typically undivided roadways. Poles should be located on one side of the street which has the least conflicts with utilities.

As long as there is a minimum of a 4’ grass parkway between the back of curb and the sidewalk, the poles should desirably be located in the grass parkway. The minimum distance from the back of curb to the center of the street light pole should be 3’. If a 3’ pole setback cannot be achieved, consideration should be made to move the pole 1’ behind the sidewalk. Longer bracket arms can be used to accommodate poles located behind the sidewalk.

Any pole located near a residential or commercial drive entrance should be located a minimum of 3’ from the edge of the drive or concrete wing. The designer should always be careful not to mount a pole in a location that could be in the path of an errant vehicle that may be backing out of the driveway. An example would be on a curved drive entrance.

The designer should also coordinate the location of all poles with existing trees, such that the fixture does not extend into the tree canopy or such that the tree canopy does not block the light output from the fixture.

Occasionally collector streets will be constructed with a raised median the entire length or possibly on the approach of an intersection. Poles can be located within the median with luminaires mounted at 180 degrees to each other in order to provide lighting on each side of the median.

Where collector streets are designed with more than two lanes, such as in commercial areas where the roadway widens out to include multiple through lanes and turn lanes, it may be necessary to light the street from both sides in order to achieve the required lighting criteria. The desired pole arrangement in this case would be staggered across the street.

4.4.3. Pole Location Preferences on Undivided Thoroughfare Streets: On undivided thoroughfare streets, the light poles will generally be located on one side of the roadway, usually due to overhead power lines on the other side. The side selected to locate the poles on should be based on conflicts with overhead and underground utilities. Where situations allow, consideration should be given to a staggered arrangement if that provides the best lighting.

At approaches to intersections, where the roadway widens out to include turn lanes, it may be necessary to light the street from both sides in order to achieve the required lighting criteria. The desired pole arrangement in this case would be staggered across the street.

4.4.4. Pole Location Preferences on Divided Thoroughfare Streets: Street light poles with two luminaires oriented 180 degrees apart should be located in the center of raised medians in the case of divided thoroughfares. It is acceptable to locate street light poles in medians measuring a minimum of 4’ from back of curb to back of curb, since all poles will be mounted on breakaway supports.

If the center median is depressed instead of raised, the poles should be located on the outside curb lines. The minimum distance from the back of curb to the center of the street light pole should be 3’. The arrangement of poles on the outside edges would preferably be staggered, but will vary depending on how wide the median is and how many lanes are in each direction.

At approaches to intersections, where the roadway widens out to include multiple turn lanes, it may be necessary to light the street from both sides in order to achieve the required lighting criteria. The pole arrangement may be staggered to the median, opposite the median or staggered across the street, which ever provides the overall best lighting levels and pole spacing.

4.5. Overhead Utility Line Clearance Requirements: Overhead power lines or lower hanging cable lines should not be in contact with street light poles or luminaires. A minimum of 3’ horizontal and vertical clearance shall be maintained from any non-electric lines such as cable TV lines, aerial fiber lines, etc. Vertical and horizontal clearance to electric power lines shall be in accordance with KCP&L requirements and varies according to the line voltage. For lower voltage lines, the vertical and horizontal clearance should be in accordance with KCP&L Code Requirements DWG 130.1-12. The designer shall be responsible to determine if adequate clearance can be achieved and make adjustments to the pole locations or coordinate utility relocation if necessary. Whenever the vertical or horizontal distance from the nearest line to the pole or luminaire is less than 10’, KCP&L requires the line to be sleeved temporarily during the pole erection. The contractor will be required to contact KCP&L and coordinate the time the sleeves are necessary and to pay KCP&L a fee for their services.

4.6. Conduit Location Preferences: On residential and collector streetlighting designs or undivided thoroughfare designs, it is desirable to run the electrical conduit in a straight line from pole to pole or pole to junction box. Desirably, the conduit should be located in the grass parkway between the back of curb and the sidewalk. In case of conflicts, the conduit may be located under the sidewalk as long as the conduit sweeps out from underneath the sidewalk to enter junction boxes and poles. Conduit installed parallel to the street should not be installed under the roadway or curb. Conduit should be installed under the street only when crossing from one side to the other.

On divided thoroughfare projects, where poles are located in the medians, the conduit location depends on the width of the median and whether the median consists of a concrete base with brick pavers or if the median consists of grass and/or landscaping. The design layout should indicate which of the “Miscellaneous Conduit Details” applies to each street light pole. The various “Miscellaneous Conduit Details” are shown on the General Notes and Legend Sheet in the Standard Details. Theses details should be consulted while reviewing the following discussion which outlines both situations.

4.6.1. Brick Paver Medians: When the median is a concrete base with brick pavers, the conduit should be installed near the centerline of the median and run in a straight line from pole to pole. At intersections, conduit runs from median nose to median nose should be offset slightly so it is not directly under the proposed object marker sign post that will be located directly behind the concrete median nose. This allows the sign post to be driven into the ground at the correct location without damaging the conduit.

4.6.2. Grass or Landscaped Medians: When the median consists of grass or landscaping, the conduit should be shown to be installed 3’ behind the median curb and swept into the center of the median at each street light pole location. This allows the median to be landscaped between street light poles without the danger of cutting the conduit or cable in the future. Conduit runs from median nose to median nose should be offset slightly so it is not directly under the proposed object marker sign post that will be located directly behind the concrete median nose. This allows the sign post to be driven into the ground at the correct location without damaging the conduit.

Conduit crossing the header between brick paver medians and grass medians should transition from the center of the median under the brick pavers, to within 3’ from the back of the median curb.

4.6.3. Coordination with Traffic Signals at Intersections: At signalized intersections, the streetlighting conduit should tie into the traffic signal service box located near the median nose. The streetlighting cable should be located in the traffic signal conduit runs around the intersection instead of continuing directly from median nose to median nose through the center of the intersection.

4.7. Junction Box Locations: Junction boxes should be installed whenever a branch circuit enters the main circuit. The junction box is used as a splice point for the cables that control the same circuit, as a future splice point for a branch circuit, or a pass through to facilitate ease of cable pulling. The following conditions in which junction boxes should be installed are described in more detail below.

4.7.1. Proposed or Future Branch Circuit at Intersections: Junction boxes are not required on both sides of a street crossing. The junction box should only be installed on one corner to provide an opportunity to tie into a branch circuit either in conjunction with the current plan or in the future. The junction box should be installed on the corner in which the street light circuit on the side street will most likely be installed. See the following illustration.