"Three supplies and one leveling" refers to the preconditions for the commencement of capital construction projects, specifically:

water, electricity, road and site leveling. Water supply (especially water supply); electricity (construction electricity is connected to the construction site and meets the construction conditions); Road (the off-site road has been paved to the entrance around the construction site to meet the vehicle access conditions); site leveling (the proposed buildings and conditions are basically flat on the site, without mechanical leveling, and can enter the construction state simply by manual leveling), which is referred to as "three supplies and one leveling".