Fire insurance rating (ISO)

Rural Fire Protection – ISO and Rural Water Supplies

For those who live or are perhaps planning to live in a rural area, questions often arise about fire protection, insurance coverage, and the effects of the rural setting on insurance rates.  Unlike well-developed urban settings, where there are likely to be established water distribution systems with fire hydrants every few hundred feet and possibly even a fire station every few miles, fire protection and firefighting water supplies in the rural environment oftentimes can vary significantly.  The following information is intended to offer guidance towards answering some of those questions.

Insurance Services Office (ISO) –

The Insurance Services Office is a nationally recognized organization that evaluates and audits communities, and then issues a fire protection class rating which the insurance industry uses to establish their fire insurance rates.  The evaluation includes assessment of the fire department that provides the community or area with fire protection, the water supply and/or water distribution system and their capabilities to deliver water for fire fighting, and the communications systems that are utilized to report and dispatch the fire department to fires.  ISO Protection Classifications range from one (1) to ten (10), with a one (1) being the best possible protection class and ten (10) essentially meaning there is minimal or no fire protection available for the property.  ISO generally considers only commercial properties for its audit/assessment database however the Protection Class rating applies to both commercial and residential properties.  The Protection Class rating can also vary within a given community or jurisdiction based upon the driving distance from the fire station to the property (greater than or less than five (5) miles) and whether or not the property is within one thousand feet (1000 feet) of an approved water source for fire fighting.  An approved water source must provide a minimum of 250 gallons per minute (GPM) flow for a minimum of two hours in duration, or a total of 30,000 gallons.  Depending upon the property (structure) size and type, the minimum GPM may be significantly higher. 

Effective in August of 2014, ISO has adjusted their Protection Class Rating System in order to afford more options for properties that may be greater than five (5) miles from a fire station, and/or where an approved water supply is greater than or less than 1000 feet away.  In Volusia County, those living in the unincorporated area or the cities of Pierson, Oak Hill, or Lake Helen, the following Protection Classifications may apply:

Protection Class and Description

4     Within 5 road miles of a fire station and within 1000 feet of a creditable water source.
4Y    Within 5 road miles of a fire station, but more than 1000 feet of a creditable water source.
10W   More than 5 miles, but less than 7 road miles of a fire station and within 1000 feet of a creditable water source.
10       More than 5 road miles of a fire station and more than 1000 feet of a creditable water source.

Water Supply Options in the Rural Setting –

Where public water distribution systems with fire hydrants do not exist, the fire department must consider alternatives for obtaining an adequate supply to fight fires.  In rural areas, Volusia County Fire Services utilizes tenders (fire trucks that carry 1500 to 2400 gallons of tank water) to help provide or supplement the water supply for a fire response.  Once the tender is emptied, the apparatus must be sent to a fill site to refill with water and then return to the fire incident scene.  This process takes time to implement, and requires manpower and equipment to support it.  Therefore, the closer a source of water is to the fire incident scene, the faster and easier it is to provide or sustain the amount of water required to manage the fire emergency. 

The following are some examples of rural water sources that may be utilized for supplying water for firefighting purposes:

Drafting Sites – 

Drafting sites are fire department approved locations adjacent to a static source of water such as a river, lake, or large pond where fire apparatus can be driven up to the edge of the body of water and utilize a “suction hose” to draw water from the source.  Typically, these are dedicated boat launching ramps or paved or hard packed driveways that are designed to support the weight of a fire truck, and enable the apparatus to get close to the water.  Some drafting sites may have a dry hydrant installed for ease of fire department setup (see dry hydrant below).

Dry Hydrants –

Dry hydrants are permanently installed piping configurations that utilize a buried large diameter (minimum 8”-10”) pipe that extends out into the static water source, above the bottom and at a depth that assures water will always be available (based upon 100 year drought calculations).  The underwater opening to the pipe has a strainer on it to prevent objects and debris from entering and plugging the pipe.  The piping configuration also utilizes a “riser” which terminates approximately 2-3 feet above the ground with a horizontal 4-1/2” or 6” threaded outlet (fire department specified), and has a removable cap on it to prevent debris from entering it when it is not in use.  The outlet is where the fire apparatus attaches its suction hose to draft water from the water source.  The source of water must be engineering-certified to be capable of delivering water to the hydrant under fifty (50) year drought conditions.  Specifications for installing dry hydrants can be obtained from the fire department of jurisdiction. (See attachment)

Horizontal Wells –

Horizontal wells provide a somewhat unique source of firefighting water in that they utilize the ground water contained within the soil strata as the supply.  The well does not tap into the aquifer as its source, but collects the water through specially designed drain tubing that is buried about 20 feet below the ground surface and at lengths from a few hundred feet to over a thousand feet, depending upon the volume of water and flow desired.  It should be noted that not all soil types are compatible with this technology and soil sampling and hydro-geologic analysis is generally required to assure there is adequate field permeability and hydraulic capacity within the soil to allow for such an installation.  In sandy soils typical in much of Florida, there can be as much as one million gallons of ground water available per acre of land.  The underground tubing is attached to a riser pipe, similar to that of a dry hydrant as described above.  The ground water capacity must be engineering-certified to be capable of delivering water to the drafting hydrant under fifty (50) year drought conditions. 

Irrigation Wells –

Irrigation wells or a dedicated “fire well” can be used to provide a source of firefighting water supply.  These systems are drilled into the aquifer and utilize either an electric motor or an internal combustion engine to power the pump.  Permitting is usually required, and they must meet specific requirements that are established by the fire department.  A minimum casing size of four (4) inches is needed and the well must provide a flow of at least 250 gallons per minute and have a 2-1/2” or larger outlet (specified by the fire department).  The fire department must be able to gain access to the connection and pump controls, and be able to start and operate the pump at any time, 24/7/365 (any time, any day/year).  The source of water must be engineering-certified to be capable of delivering water under fifty (50) year drought conditions. 

Agricultural operations may often place a valve and fire department connection onto existing irrigation wells/pumps to enable them to serve as a creditable water source.

Above/Below Ground Storage Tanks –

Above and below-ground storage tanks can be utilized for housing firefighting water supplies in the rural setting as long as they are of sufficient size.  The approved storage capacity also depends upon the size/capability of their refill system.  Since ISO requires a minimum flow of 250 gallons per minute, sustainable for a minimum of two hours, to be a creditable source, tank capacities usually are required to be at least fifteen to twenty thousand gallons.  An automatic refill system is also needed to maintain the stored supply at full capacity at all times when not being used.  This is usually accomplished by the installation of a level control switch attached to a well supply pump or control valve on a pressurized water source.  Underground tanks require a drafting pipe (dry hydrant connection) or an access port large enough for the fire department to insert a suction hose to draft with.  Aboveground tanks should either have a fire department drafting connection  or be valved with a minimum of a 2-1/2” gate or ball valve, located at the bottom of the vessel.  All tanks must have open air vents of sufficient size to allow pressure equalization and prevent damage to the tank during filling and drafting operations.

For further information, please contact your local fire department.  Your insurance carrier can provide you with the ISO information and specific requirements that may pertain to their policies.

UNDER-ABOVE-GROUND-STORAGE-TANKS

DRY-HYDRANT-CONSTRUCTION