flooding.  Following  these  routes  also  makes  it  difficult to  deliver  materials. 6. Avoid disrupting the environment.  Taking into consideration  environmental  codes  and  regulations,  the engineer  should  select  routes  that  cause  the  least disturbance  to  the  environment.  The  engineer  should also  consider  aesthetics  when  reviewing  possible  routes. ELECTRICAL  DISTRIBUTION DRAWINGS The  following  text  discusses  the  types  of  electrical distribution drawings that you may prepare when you are  assisting  the  engineering  officer  in  a  construction battalion or when assigned to the engineering division of a public works department. Electrical Distribution Plans The type and extent of information placed on an electrical distribution plan depends on the purpose of the plan.  Figure  2-14  is  a  distribution  plan  for  a  Navy activity that is taken from that activity’s master plan. As you can see, it shows the routes of the distribution circuits,  but  it  only  identifies  them  as  aboveground  or belowground.  For  this  plan,  you  would  find  a  brief narrative description of the circuits located in the text of the master plan. Obviously, a drawing of the type shown in figure 2-14  is  of  little  use  to  an  engineer  or  lineman  who requires  specific  information  about  the  distribution system.  For  this  purpose,  you  should  prepare  a  detailed electrical distribution plan. The detailed plan is drawn using  the  proper  electrical  symbols  found  in  ANSI Y32.9.  Similar  to  figure  2-14,  the  detailed  plan  shows all  buildings  and  facilities  and  the  routing  of  the distribution lines. In addition and as applicable to the type of system you are drawing, you also should include the  following  information: 1.  The  source  of  power  (power  plant,  public utility  line,  substation,  or  standby  generator  with electrical  data). 2. The number, type, and size of underground conduit or cable ducts and the size, number, voltage, and type of cable. 3. Where cable runs are made without installed ducts,  indicate  the  location,  dimensions,  and  description of splice boxes. 2-11 4. Identify and describe all electrical manholes and  handholes  by  location,  identification  number,  type, dimensions,  and  top  and  invert  elevations. 5.  Describe  all  transformer  vaults,  either  above- ground or belowground, with dimensions, top and invert elevations,  numbers,  type,  and  electrical  data. 6. Electrical data for all substations. 7.  The  location switches. 8.  The  number, overhead  conductors. 9.  The  location, and height of all poles. and  type  of  all  sectionalizing size,  type,  and  voltage  of  all identification,  material,  class, 10. The number and rating of all pole-mounted transformers. 11.  Street-lighting  systems,  light  standards,  type, and rating of lights. 12.  The  number,  size,  voltage,  and  type  of  street- lighting  circuits. 13.  Note  any  buildings  containing  street-lighting transformers  and  control  equipment  together  with  type and rating of transformers. To simplify the drawing, it is common practice to place much of the above information in appropriate schedules. For example, in an overhead distribution plan, you need only show the location and identification number of the poles on the plan. The material, class, and height of the poles can be placed in a pole schedule that is listed by the pole identification numbers. Site Plans Site plans are discussed in the EA3 TRAMAN. As you  should  recall  from  your  study  of  that  training manual, a site plan furnishes the essential data for laying  out  a  proposed  facility.  It  shows  property boundaries, contours, roads, sidewalks, existing and proposed  buildings  or  structures,  references,  and other significant physical features, such as existing utility lines. For small, uncomplicated buildings, you can often show all proposed electrical and other new utility lines on the same site plan. For the average facility,  however,  it  is  common  practice  to  prepare separate utility plans that are included, as applicable, in  the  plumbing  and  electrical  divisions  of  a  set  of project  plans.