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One of our most important duties in the Emergency Services Division is to communicate... and to provide for communications during local emergencies and disasters.  In other words, collecting, interpreting and providing valuable and pertinent information to the public and to local governments during an emergency in an efficient and timely manner.  We accomplish this task using several different methods.  This section of our web site is devoted to introducing you to some of our programs and technological systems that are in place and ready for any community emergency.

Severe Weather Tracking System

Radar Image from NOAA PortSevere weather is Washtenaw County's highest rated potential disaster risk... and we take this potential quite seriously.  Our primary method of acquiring severe weather tracking data is the NOAAPort C-Band DVB-S satellite downlink system.  This downlink provides the Emergency Operations Center with a continuous 10 MB/S feed that includes all images generated by the National Weather Service's Doppler radar network, GOES visible, infrared, and water vapor imagery, all forecast models, and all text generated bulletins within two seconds of being generated or issued.  This downlink  utilizes two 3.7-meter dishes (a primary and a backup), a dual receiver system, a data ingest server and a GEMPAK image processing server... both utilizing dual quad-core processors and 64-bit Linux operating systems.  In addition, two isolated servers and a receiver system are set-up and ready to take over should the primary technology ever fail.


Weather Monitoring Station

The Emergency Operations Center monitors several weather conditions around the clock.  Our weather station monitors and automatically logs data and trends for temperature, relative humidity, barometric pressure, wind speed, wind direction, rainfall accumulation, and cloud-to-ground lightning strikes within 100 miles of the Emergency Operations Center.  The unit is connected to a PC for data logging and a VGA distributor for simultaneous display in the EOC and in the Central Dispatch center.



Radio Communications Systems

The 800 MHz trunked public safety radio system is the county's primary public safety communications system.  The original system constructed back in 1986 was recently replaced by the Emergency Services Division with a state of the art, three million dollar, 12-channel, 2-site simulcast backbone with drastically extended range and capability... and was customized for emergency services communications.  All Washtenaw County law enforcement agencies, numerous state and federal agencies, most county and local government units, Road Commission trucks, EMS, Emergency Services and several fire departments utilize this system for dispatch and car-to-car communications.


County-wide "Quick Call" Alerting System

This county wide VHF paging system was developed in the early 80's to provide immediate 24-hour a day notification for local hospitals, radio stations and 9-1-1 centers when severe weather watches and warnings are issued, when roads or freeways are closed due to major accidents, or for any other community emergency such as an evacuation due to chemical accidents.  This system was recently expanded last year to include all county government facilities as well as several schools, factories and businesses.  If your organization needs immediate notification about these serious events, the equipment is relatively inexpensive (around $400) and will work from any location in Washtenaw County if properly installed.  Contact us at (734) 973-4900 for more information.  If you have a programmable police type scanner, you can also monitor these messages on 158.760 MHz.

National Emergency Alert System

Washtenaw County and Lenawee County have a joint Emergency Alert System, designed to provide our citizens with timely information and important directions pertaining to emergencies.  The system can be activated by Emergency Managers or by state and federal officials, such as National Weather Service meteorologists.  This system is the new and much more advanced version of the "Emergency Broadcast System" that links all radio and television stations, cable TV providers, and Emergency Operations Centers in a given operational area (Washtenaw & Lenawee counties, in our case) along with the National Weather Service, state and federal emergency services agencies in order to make sure that the public is well informed about risks to their health and safety.

Washtenaw County's Emergency Alert System stations are WEMU at 89.1 FM and WWWW at 106.7.  These stations are linked to both the Emergency Operations Center and the National Weather Service 24-hors a day in order to quickly warn the Washtenaw County community about serious emergency situations.

Broadcasters will immediately interrupt programming and initiate EAS messages for the following bulletins:

  • Tornado Warning

  • Severe Thunderstorm Warning

  • Blizzard Warning

  • Flood and Flash Flood Warnings

  • Civil Emergency Message

  • Chemical Emergency

  • Immediate Evacuation

  • Emergency State or Federal Messages

Broadcasters will initiate EAS messages at the next available break in programming for the following bulletins:

  • Tornado Watch

  • Severe Thunderstorm Watch

  • Winter Storm Watch

  • Winter Storm Warning

  • Flood or Flash Flood Watches

Portable Radio Communications

When a large emergency strikes, communications with all personnel sent into the field to manage the emergency is critical.  Damage assessment crews, law enforcement personnel, staff activated for shelter operations, and support personnel from other county, state and federal agencies need portable communications to coordinate the response.  The Emergency Services Division keeps a full supply of portable radios standing by and spare batteries fully charged... ready for action at the drop of a hat.

Amateur Radio Communications

Amateur radio is one of the most valuable resources to Emergency Managers across the country and around the world!  Washtenaw County is fortunate to have hundreds of dedicated "ham radio" operators and several communications systems in place that jump into action whenever a large-scale crisis takes place... especially during times of severe weather.

There are 3 separate but closely coordinated Amateur Radio programs, and several communications systems (called "repeaters") that are in place in Washtenaw County.  First we'll cover the programs, then the communications systems.

Amateur Radio Programs:

Skywarn is a volunteer partnership established by the National Weather Service and advanced by local emergency managers across the nation that utilizes FCC licensed amateur radio operators who take additional severe weather detection training and report severe weather events as they happen and in real time... using established communications links (called "nets") with county Emergency Operations Centers which are in direct contact with weather service meteorologists. This system combined with the new severe weather tracking capabilities of the National Weather Service and in our Emergency Operations Center has led to much more accurate and timely warnings for the public.  Over the past several years we have expanded this system to include police officers, paramedics, firefighters and concerned members of the public who are interested in attending Skywarn Spotter training, utilizing the 9-1-1 telephone system to report severe events.  A truly successful partnership to say the least!

The Radio Amateur Civil Emergency Service was created by the Federal Communications Commission in the 50's as a system to provide local and state governments with a communications "insurance policy" during the cold war.  In the event that the government were to experience a large area or system wide communications failure due to the likes of Electromagnetic Pulse ("E.M.P.") when nuclear weapons detonate, a fully redundant communications system had to be ready for deployment... and the clear choice was volunteer amateur radio operators with their personally owned equipment.  Since the cold war has ended, the R.A.C.E.S. system has proven itself to be an invaluable asset during natural disasters, so the system was enthusiastically left in place.  Amateur Radio operators who volunteer to be on-call for RACES activations must first complete a F.E.M.A. independent study course to familiarize themselves with disaster response systems and to register with their local emergency management division.  Check out the Washtenaw County R.A.C.E.S. web site for more information.

The Amateur Radio Emergency Service was developed by the American Radio Relay League, the largest  consortium of Amateur Radio operators in the United States.  The A.R.E.S. program provides for a system of providing licensed operators for various safety and emergency functions across the country.  Agencies that the A.R.E.S. organizations serve nationally include local Emergency Management, American Red Cross, and other groups who need communications resources during a crisis or large public event.


Amateur Radio Communications Systems:

Primary Application

Secondary Application

Frequency (offset/tone)

Call Sign/Trustee


Skywarn and A.R.E.S


145.150 (-/100Hz)


Coverage Map


Skywarn and A.R.E.S.

146.920 (-/100Hz)




Satellite Telephone

This secure telephone system would be utilized in the event that we were to experience a disaster that completely disabled our primary communications infrastructure (such as telephone lines, telephone central offices, and cellular telephones).  There is even a spare satellite parked right next to the primary one, in case the primary fails for any reason.


Service Center Telephone System

Our new primary telephone system is a Fujitsu F9600.  This is Fujitsu's flagship PBX, providing a seamless migration path with as few as 40 lines to as many as 9,600 lines, and it works in conjunction with the Octel voice mail package. The system controls all business telephones at the service center complex including Sheriff, Environmental Services, Library, Cooperative Extension, Drain Commissioner, Court Services, Facilities and Emergency Services, and it is supported by the EOC's emergency generator system.


Emergency Operations Center Telephones and Backup System

Advanced technology is great... but backups to the technology are not only wise but essential.  In addition to the new Fujitsu PBX, the Emergency Operations Center has over 30 non-PBX "Centrex" 7-digit outside single lines installed and ready for action.


The county's Emergency Operations Center uses a high capacity Sharp FO-4400 laser facsimile machine with group faxing capabilities, and another FO-4400 and Hewlett-Packard OfficeJet as backups.



Cellular phones are obviously essential to any Emergency Services Division.  And though we have a good supply of them, and they come in very handy when handling local emergencies, the fact of the matter is that they will not be very useful in a community wide disaster.  Cellular telephone sites do not have emergency power sources, they are as susceptible to lightning damage like any other communications system, and they utilize telephone circuits and switches like regular telephones.  They also have a per site user limit.  It is for all these reasons that cellular telephones can not be depended upon during a disaster!

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