The City of Three Rivers is scheduled to conduct annual maintenance on the Outdoor Warning Siren (OWS) system on Monday, May 21. A service technician will be visiting each remote site to perform maintenance and inspections. Test activations will occur throughout the day in order to confirm the system is operating properly. Activations will include “growl testing” (a short, limited volume test) and full tests lasting several minutes. If inclement weather is in the short-term forecast, the maintenance will be rescheduled and no testing will occur.