Nuclear power plants for desalination plants and the build out water pipelines and rail into the Sahara desert from the ocean. Use irrigation canals covered in

Nuclear power plants for desalination plants and the build out water pipelines and rail into the Sahara desert from the ocean. Use irrigation canals covered in solar power panels for pumps etc. Plant vegetation and build up forests slowly. Slowly expand across the desert and connect both ends the block off grids and repeat irrigation and planting until the desert is gone.