Low Power FM (LPFM) Radio provides means to broadcast to residents who have normal battery-powered radios. Range of 2-4 miles (one station might cover all of Palo Alto) depending upon antenna location (height and obstructions). Stations operating at lower power would be appropriate for larger neighborhoods.
Licenses are effectively unobtainable (below), but unlicensed operation is allowed: You can broadcast in unused portions of the spectrum, but you must find those frequencies and must immediately yield them should the licensee start transmitting.
During Katrina, LPFM demonstrated utility - a station was set up outside the Houston Astrodome to keep the evacuatees there informed.
Problem: Quick search of documents did not reveal any thought about a mechanism for preempting frequencies during an emergency, and pre-allocating them to the various agencies. Recognize that repeaters - a major use of these frequencies - are typically configured for unattended operation and have backup systems to keep them operating. Thus, preemption likely involves having someone physically visit the repeater and shut it off.
Uses:
If Tasks:
Transmitters themselves are relatively cheap: web search shows kits available starting just above $100. Need to determine what accessories are needed, for example:
Congress limited LPFM to rural areas at the behest of the big radio corporations (including NPR). Those corporations "invested" millions to obtain this decision: The National Association of Broadcasters alone purchased $2.2M of "access" to Congress. This all but squashed the LPFM movement. However, Congress' decision was so transparently corrupt (its rationale had been repeatedly disproved) that there was concern that Congress might reverse itself. Consequently, the big radio corporations engaged in a variety of tactics to lock up spectrum - translator stations were a favorite ploy. A moratorium was imposed, but is about to expire.
Even if one were to obtain a license, you must meet a minimum of on-air time (5 hours per day?).
Some LPFM frequencies have been licensed to governments for purposes such as broadcasting local traffic information on highways. All these uses are valuable during a disaster or other emergency, but the government agency might decide that other uses were even more important and re-purpose the transmitter.
Additionally, if the agency holding a license has not designed their transmitters for survivability (power and downloading messages), they may be off-the-air during a disaster.