This means that you'll be able to search for NAICS codes directly (if that's your jam). We'll do the math; let's make better data on public procurement together.
Possible NAICS Codes
221310 – Water Supply and Irrigation Systems
221320 – Sewage Treatment Facilities
926130 – Regulation and Administration of Communications, Electric, Gas, and Other Utilities
237110 – Water and Sewer Line and Related Structures Construction
312112 – Bottled Water Manufacturing
221210 – Natural Gas Distribution