Falls in wastewater system are a danger as well, the use of fall protection devices can prevent serious injury. Good house keeping can help by removing slipping or tripping hazards. Fire and explosion in wastewater systems is a concern as well. You can find them on the Internet. There have been many documented injuries from heavy lifting in wastewater treatment facilities.
Most equipment found in wastewater systems is quite heavy.
Proper technique for lifting objects is necessary to prevent injury. Crush injuries from this equipment is a threat as well. Develop and integrate a safety program into your work environment. A facility safety officer or safety committee can help to focus on safety and health related issues. While prevention is always the best answer, accidents continue to happen.