What must be determined before excavation can begin?

Before excavation can begin, it is essential to determine the location of underground installations, often referred to as "811 locates." This process involves identifying any existing utilities, such as water, gas, electricity, and telecommunications lines that may be present underground. Knowing the precise location of these installations is crucial to prevent accidental damage during excavation, which can lead to service disruptions, safety hazards, and costly repairs.

Utility companies typically provide this information as part of a "811 call," which is a national service for locating underground utilities before digging. This proactive measure ensures the safety of workers and the public, as well as compliance with legal and regulatory requirements. Understanding the location of these utilities forms the foundation for all subsequent excavation planning and execution, making it an indispensable first step in the overall excavation process.

Other factors like depth of the trench, weather conditions, and soil composition are important considerations in excavation projects; however, they all become secondary to the urgency of identifying underground installations to avoid potential accidents and delays.