Typical Trench Detail
- Before digging call for Underground locates: (800) 332-2344 or 811 at least 48 hours prior to digging.
- All Trenches must be a minimum of 36” deep.
- If a 36-inch depth cannot be achieved, contact Lane Electric’s Engineering Department at (541) 484-1151.
- If trench is to be a joint trench (shared with other utilities) the following separations must be maintained:
- 24 inches between gas and electric lines
- 12 inches between water and electric lines
- 24 inches between sewer and electric lines
- 12 inches between communications and electric lines
- If trench is to be power only, the ditch needs be wide enough to accommodate the conduit, i.e. a 4-inch ditch-witch trench is sufficient.
- If the trench is dug through rough, rocky terrain, the conduit must be bedded with a minimum of 4 inches of sand.
- All conduits must be gray Schedule 40 electrical PVC.
- All primary conduit (7200V) must be 3 inches in diameter with 36-inch radius long sweeping elbows at any 90° bend.
- Secondary (120/240V) conduit for a 200 Amp. service must be 3 inches in diameter, with 36-inch radius long sweeping elbows at any 90° bend.
- Secondary (120/240V) conduit for a 400 Amp. service must be 3 inches in diameter, with 36-inch radius long sweeping elbows at any 90° bend. (See Exhibit A)
- Street or security lighting conduit must be 1.25 inches with 36-inch radius long sweeping elbows at any 90° bend.
- There will be no more than 270° of bend (3- 90° bends or 2- 90° & 2- 45°) in any one run of conduit, primary or secondary, between devices.
- All Primary conduits must be proved by mandrel. See Exhibit I for mandreling details.
- New mule-tape rated at 2500# must be left in all conduits, primary and/or secondary. Mule-tape must move freely in conduit and have sufficient length (10 feet or greater) beyond each end to accommodate installation of conductor. Mule-tape can be picked up at Lane Electric at no charge.
- Where transformers and primary or secondary junction boxes are to be installed, specifications must be obtained from Lane Electric’s Engineering Department. (See Exhibits B-G for common facilities.)
- After the Trench is dug and conduit installed, call Lane Electric (541) 484-1151 to have an inspection scheduled by the Engineering and Operations Department.
- After the Trench and the conduit are inspected, the Trench may be back-filled. Conductor cannot be installed until trench is backfilled.
Note: No electric lines, primary or secondary, may be placed under a concrete foundation or slab.
For more information, view the Typical Trench Detail Information (PDF).