Which factor is related to the water supply in sprinkler spacing considerations?

• A. Temperature
• B. Evapotranspiration
• C. Available pressure
• D. Rainfall

Answer: (C)

The key factor in sprinkler spacing related to the water supply is the available pressure. Spacing is built around how far and how reliably a sprinkler head can throw water at the pressure the system can deliver. The discharge rate and throw radius of a head depend on operating pressure; if the available pressure is low, the head can’t reach as far, and wider spacing would leave gaps in coverage. Designers verify the head’s required operating pressure and friction losses in the piping to ensure the system can achieve the intended spacing with the chosen heads and flow. If pressure is insufficient, you adjust by reducing spacing or selecting heads with lower pressure requirements or different flow characteristics.

Temperature, evapotranspiration, and rainfall influence how much water the landscape needs, not how far water can travel from a head, so they don’t determine spacing.