New England’s construction boom is creating a playing field where companies are competing to be No. 1 in the business of No. 2.

Boston’s wave of construction sites across the city has kept the port-a-potty industry flush with new demand, and the market is rushing to keep its head above water from all the new orders. New suppliers are entering the field and existing companies are expanding to fight for market share in Boston’s game of thrones, the Boston Globe reports.

Woburn-based Throne Depot started 10 years ago with 26 port-a-potties. The company has since increased its commode roster to 2,100, with 500 units being purchased in the last year. Flush Services of North Reading has been equally awash with new business.

“This last year, we had to buy at least 150 toilets [some months] just to meet demand,” Flush Services Director of Events Parker Ganassin told the Globe. “We’ve grown to the point where we probably need a new building.”

Callahan Construction Managers Chief Operations Officer Doug Morrison told the Globe he guessed there were 10 to 15 port-a-potty companies in the region, and many have only started in the last few years. The Boston Planning & Development Agency lists over 100 construction projects in the city, and 42 are active with construction. Labor regulations recommend one toilet for every 20 workers, and some larger construction sites require as many as 500 units.

“Any time there’s a gathering of an outdoor workforce, there’s certain basic things about nature that you cannot change,” United States Services Senior Vice President of Marketing and Communications Asit Goel said to the Globe. “And demand has been very good for our products and services.”