| # | Company name | Role | # of projects |
|---|---|---|---|
| 1 | Harris Civil Engineers, LLC | Sanitary engineering | 6 |
| 2 | Helman Consulting Engineers Ltd. | Sanitary engineering | 5 |
| 3 | HeRo Sp. z o.o. | Sanitary engineering | 4 |
| 4 | Hidrotech Saneamento e Proteção | Sanitary engineering | 17 |
| 5 | HPI HIMMEN Ingenieurgesellschaft mbH & Co. KG | Sanitary engineering | 3 |