Background on Ann Arbor’s Outdoor Warning Siren System Review

In early 2026, the City of Ann Arbor asked the community for feedback as it considered whether to retire the city’s outdoor warning siren system.

Ann Arbor has 22 outdoor warning sirens. The system is aging and requires repairs and ongoing maintenance. City staff estimated repairs would cost approximately $60,000 annually for the next three years, followed by about $17,000 per year in ongoing maintenance.

At the same time, emergency warning technology has changed significantly. Wireless Emergency Alerts can automatically send detailed warnings to compatible cell phones in an affected area, while A2 Emergency Alerts can provide text, email and telephone notifications. These systems can provide information about the nature of an emergency and instructions for what people should do, while sirens are designed only to get the attention of people outdoors and prompt them to seek additional information.

Before making a decision about the sirens, the city sought community input through an online survey open from Feb. 27 through March 31, 2026. Nearly 3,900 responses were submitted.

The survey was not a scientific or statistically representative survey. Participation was voluntary, respondents were self-selected, and the results should not be interpreted as representing the views of all Ann Arbor residents. Instead, the survey was intended to help the city understand the perspectives, experiences and concerns of people who live, work, study and spend time in Ann Arbor.

Most Respondents Favored System Maintenance

The message from survey respondents was clear: respondents overwhelmingly opposed retiring Ann Arbor’s outdoor warning sirens and favored maintaining the system.

Most respondents described outdoor warning sirens as an important public safety tool. Many also expressed limited confidence that cell phones, television, radio, weather apps, social media and other electronic warning methods could fully replace the sirens.

Several themes appeared repeatedly in the survey responses and written comments.

Multiple warning methods provide important redundancy. The most common theme was that emergency communications should not depend on a single technology. Respondents generally supported mobile and other electronic alerts but viewed them as supplements to, rather than replacements for, outdoor sirens. Many said an emergency warning system should have overlapping methods so that the failure or unavailability of one system does not prevent people from receiving a warning.

Phones and other electronic devices are not always available or noticed. Respondents gave many examples of situations in which someone might not receive a phone alert: a phone may be turned off or silenced, left in another room, have a dead battery or be outside cellular coverage. People may be sleeping, working, exercising or intentionally spending time away from their devices. Some respondents also noted that power, internet or cellular service can be disrupted during severe weather or other emergencies that prompt warnings.

Sirens are particularly important for people who are outdoors. Respondents frequently mentioned people using parks and trails, walking or bicycling, attending sporting events, festivals and the Ann Arbor Art Fair, doing outdoor work or otherwise spending time outside. Visitors may also be unfamiliar with local alert systems or may not have enrolled in local notification services. Respondents viewed sirens as a way to reach a large outdoor population quickly without requiring any advance registration or particular device.

Access and equity were significant concerns. Many comments focused on people who may not have reliable access to smartphones, internet service or other technology. Respondents specifically mentioned older adults, children, people with limited incomes and people experiencing homelessness. Others noted that even people who own smartphones may not carry them at all times. Respondents frequently said a community warning system should reach people regardless of their access to technology.

Nighttime emergencies were a concern. Many respondents questioned whether a phone or other electronic alert would reliably wake them during an overnight emergency, particularly if a phone was silenced or located outside the bedroom. Ann Arbor’s outdoor warning sirens are not intended to be heard indoors but nonetheless were viewed by these respondents as an additional way to attract attention during a fast-moving emergency.

Respondents placed value on the urgency and familiarity of the sirens. Some respondents said the distinctive sound of the outdoor warning system immediately signals that something unusual is happening and that they should seek additional information. Several described personal experiences hearing the sirens during severe weather or other emergencies and taking action as a result.

Smaller Share of Respondents Favored Decommissioning Sirens

Although substantially fewer respondents favored decommissioning the sirens, their comments identified several considerations for the city.

Some respondents viewed outdoor sirens as outdated compared with modern alerting technology. They noted that sirens cannot explain what type of emergency is occurring, where the threat is located or what action people should take. Wireless alerts, by comparison, can provide specific instructions and target a defined geographic area.

Others questioned whether continued repair and maintenance of an aging system was the best use of public funds, particularly if more modern warning methods can reach most people more effectively. Some respondents also described monthly siren tests as disruptive or said repeated testing may make people less likely to recognize when a siren signals a real emergency.

A smaller number of respondents said they had difficulty hearing the sirens, particularly indoors. This is consistent with the intended purpose of the system: Ann Arbor’s sirens are designed to alert people who are outdoors, not to provide warnings inside buildings.

Overall Finding and Conclusion

There was strong support among survey participants for retaining Ann Arbor’s outdoor warning sirens as one part of a broader emergency warning system.

Respondents generally did not reject newer warning technology. Instead, the dominant view was that the city should use multiple, complementary methods to reach people during emergencies. Modern alerts can provide detailed and geographically targeted information, while sirens provide an additional means of attracting attention, particularly for people outdoors or people who may not receive an electronic alert.

The feedback also highlighted opportunities for continued public education about what the sirens mean, when they are activated, how they are tested and what people should do when they hear one.

After considering the community feedback and other information gathered through the review, the City of Ann Arbor decided to retain and invest in its outdoor warning siren system. The sirens will continue to operate as one component of the city’s broader emergency warning and public information system.