Criteria for distribution line route selection

The route of an LT (and HT) distribution line is the path along which poles are erected. A good route gives the shortest, safest and cheapest line that serves the consumers well and is easy to maintain.

General criteria

1. Shortest practical length: a route close to a straight line between the transformer and load clusters reduces cost, voltage drop and losses. Avoid unnecessary bends, since each angle point needs a stronger pole with stays.
2. Follow roads and tracks: lines along the road side (within the road right-of-way) give easy access for construction, operation and maintenance, and avoid crossing private land.
3. Proximity to consumers: the line should pass near the houses to keep service drops short (typically within about 30–40 m), reducing service cable cost and losses.
4. Load balance: arrange feeders so that load is shared equally among phases and feeders, and so the transformer remains near the load centre.
5. Right-of-way and land issues: prefer public land; minimise compensation, disputes and tree cutting. Avoid passing over buildings.
6. Safety clearances: maintain statutory clearances from buildings, roads, footpaths, telecom lines and other power lines (as per Nepal Electricity Regulations); avoid schools, playgrounds and fuel stations.
7. Terrain and soil: avoid landslide-prone slopes, river banks, flood plains, marshy and unstable ground; choose firm ground for pole foundations.
8. Crossings: minimise crossings of rivers, highways, railways and other lines; cross at right angles where needed.
9. Environment and aesthetics: avoid forests, heritage sites and protected areas; use ABC or underground cable in sensitive or crowded areas.
10. Future expansion: leave room for new consumers and for future upgrading (e.g. to three-phase or larger conductors).
11. Span and pole positions: keep uniform spans (about 40–50 m for LT) and place poles where they will not obstruct traffic or drainage.

The final route is fixed after a walk-over survey, considering cost, technical limits and the views of the local community.