FLH PDDM Chapter 9 - Eastern Federal Lands Highway Division

9.4.F. Other Design Elements. (continued)Conventional poles located within the clear zone shall have frangible or slip bases unless falling poles wouldcreate greater hazards.The hazard of light poles can be further reduced by placing them outside of ramp gore areas and on the insideinstead of the outside of curves.Require frangible or slip base poles in the clear zone and in medians ( 12 meters or wider) or along the outsideof the traveled way.Frangible bases are not appropriate on poles located along sidewalks or other locations where they could fallinto heavily traveled roads, on pedestrians, or where a falling pole would create a greater hazard. This isespecially applicable to those poles located on narrow sidewalks separating frontage roads form the mainroadway.Select pole locations so the luminaire's brightness will not produce excessive glare in the driver's view or causereflected glare on adjacent overhead signs.2. Fencing. Fence is usually installed to protect a highway facility from unsafe encroachment by pedestrians,livestock, etc. Generally, fencing replaces existing fence, and is usually constructed on the right-of-way (R/W)line through private lands. Some states have laws requiring fence for all State R/W. The designer needs tocheck the applicable regulations during the design process. The type of fencing and its location shall agreewith the R/W documents or be agreed to during the plan-in-hand or other reviews of the project.When the R/W line has many abrupt irregularities over short distances, fencing runs should have continuousalignment. This means some R/W corners or monuments will remain outside the fence line. Fencing on acontinuous alignment has a cleaner appearance and is more economical to construct. In rural areas, thedesigner should contact the property owners to determine locations for the fence line. In many instances, thelandowner will request a fence outside the R/W line for ease of maintenance. Attempt to hold the number offence types to a minimum on any particular project for convenience of construction.Chain-link fence may be warranted for the following:Through industrial areas.At residential developments.Through military reservations.At schools and colleges.At recreational and athletic areas.At other locations where maximum protection to prevent encroachment on the right-of-way is necessary.Generally, an 1800 millimeter high chain link fence provides protection from encroachments. Sometimes a1200 millimeter height is adequate if conditions are noncritical.Wire fencing warrants apply in all rural areas and in some suburban and urban cases. The fencing may consistof barbed wire, hog wire, and other types of metal fabric.The height of fence can be variable depending on the primary purpose of the fence, such as controlling cattle,sheep, wild animals, etc. Some wire fencing can be 2 to 3 meters high when used to control elk and deer. Insome western states, the clear distance from the ground to the first wire is important for antelope crossings.Metal right-of-way fencing can interfere with airport traffic control radar. When fencing in the vicinity of anairport, review the FAA permit to determine if the fencing will create radar interference. An alternate type offencing may be appropriate in this case.9 - 98