Construction does require water and electricity prior to commencing a job. Certain tasks, including mixing concrete and the use of electric power tools rely on water and electricity and are essential to the construction process. Likewise, site amenities for builders and contractors like toilet services and drinking water also depend on having a supply of water.
Temporary water and electricity supplies for building
Builders will generally organise distribution of these temporary services when the site is being prepared. Your builder will apply for temporary construction water from the local water supplier, which will be connected at the front of the block. This kind of temporary connection normally comes with some restrictions (e.g. the water shouldn't be used to water plants).
Temporary electrical service will also be connected prior to construction beginning; again this is the responsibility of the builder.
Once the house is completed, the necessary water supply and sewerage plumbing and the wiring will have been installed in the house. Your electricity and water supply companies will install the necessary metering and supply equipment.
If you're building in an isolated location where there's no existing access to the electricity grid, generators will be used by builders for electricity. This will be organised by the builder. It's also possible for construction companies to organise portable water facilities (including things like water tanks and pumps) for very isolated projects.