These photos show improperly installed exterior wiring at a home in Aurora Colorado. They were taken during a home inspection by my company, Magpie property inspections. Someone has routed interior rated Romex (NM) wiring along the surface of the ground outside to power lighting and electrical to a storage shed. This type of wiring should never be used outside along the ground surface and/or without being installed in approved exterior conduit. Wiring runs outside should be buried at least 18 inches deep underground between the origin and termination of the lateral run and installed in PVC schedule 40 type piping below ground, and schedule 80 type piping above ground, with approved connections and fittings, to protect the wiring and prevent damage and contact with moisture.
Direct burial of type “UF” cable under soil is probably the most common and least expensive method to run electrical lines outside. UF cable provides for hot, neutral and grounding conductors all inside a durable, sunlight and moisture resistant encasement. UF type cable looks very similar to Romex (NM) cable, but differs in that the individual conductors are encased with the jacket material found on NM cable to provide a solid weatherproof material that will resist damage and moisture penetration to a much greater degree. It too, should be buried at least 18 inches underground from origin to termination.
Any electrical work outside should be done using the appropriate materials by a qualified electrician in accordance with prevailing building codes.