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
237990 – Other Heavy and Civil Engineering Construction
238990 – All Other Specialty Trade Contractors
237110 – Water and Sewer Line and Related Structures Construction
236220 – Commercial and Institutional Building Construction
238910 – Site Preparation Contractors
237310 – Highway, Street, and Bridge Construction