What is the minimum bottom diameter for a storm sump?

What is the minimum bottom diameter for a storm sump?

• A. 12 inches
• B. 14 inches
• C. 16 inches
• D. 18 inches

Answer: (B)

A storm sump must provide enough interior space for maintenance and the installed pumping equipment, so codes set a minimum bottom diameter to ensure service access and proper function. Fourteen inches is the smallest diameter that meets that requirement. It gives room to install and service the sump pump and fittings and reduces the chance of frequent clogs or clearance issues. A smaller diameter, like twelve inches, would be too cramped for typical equipment and maintenance access. Larger sizes, such as sixteen or eighteen inches, would also work and meet the minimum, but they’re not the smallest allowed.

A storm sump must provide enough interior space for maintenance and the installed pumping equipment, so codes set a minimum bottom diameter to ensure service access and proper function.

Fourteen inches is the smallest diameter that meets that requirement. It gives room to install and service the sump pump and fittings and reduces the chance of frequent clogs or clearance issues. A smaller diameter, like twelve inches, would be too cramped for typical equipment and maintenance access. Larger sizes, such as sixteen or eighteen inches, would also work and meet the minimum, but they’re not the smallest allowed.