§ 72-622. Fire protection systems.

The fire protection system of the proposed development shall be based upon the following requirements:

(1)

Water supply. The fire protection water supply for the proposed development shall meet the following fire flow requirements:

a.

In the case of a single-family or duplex residential development of less than ten dwelling units with lot sizes of less than one acre, or in the case of a single-family or duplex residential development of ten or more dwelling units, but less than 200 dwelling units with lot sizes of one acre or more, fire wells may be utilized.

b.

In the case of a single-family or duplex residential development with lot sizes of one acre or more totaling 200 or more units, a central water system shall be utilized for fire protection water supply which meets the water flow requirements of fire services. (Refer to Table VII as a reference.)

c.

In the case of a single-family or duplex residential development with lot sizes of less than one acre, the fire protection water supply shall be provided by a central potable or nonpotable water supply or a combination of central water supply, auxiliary supply of fire wells, which will produce the water flows contained in Table VII. In no case shall the central water supply for fire protection be less than 50 percent of the required fire flow. Auxiliary water supply may be provided by a combination of tank trucks, ground tanks, cisterns, elevated storage, drafting stations on canals or reservoirs, or other methods subject to approval by the department of fire services.

d.

In the case of a multifamily residential development; a business or industrial development; or a place of assembly, the fire protection water supply shall be as defined in the most current edition of NFPA 1231 - "Standard on Water Supplies for Suburban and Rural Fire Fighting". In all cases the minimum fire flows shall not be less than required for dwellings in Table VII.

e.

A single water supply system may be used for both potable and fire protection supply provided the requirements of Table VII and/or NFPA 1231 are maintained, as applicable.

f.

The minimum time duration for required fire flows shall be in accordance with Table VIII.

TABLE VII. FIRE FLOWS FOR
GROUPS OF DWELLINGS

Exposure Distances (feet)	Required Fire Flow* (gallons per minute)
Over 100	500
31 to 100	750—1,000
11 to 30	1,000—1,500
10 or less	1,500—2,000

 

*Add 500 GPM where wood shingles would contribute to fire spread.

†Use 2,500 GPM minimum if buildings are continuous.

TABLE VIII

Minimum Flow at Source of Supply (GPM)	Minimum Duration (hours)
1,000 or less	2
1,250	2
1,500	2
1,750	2
2,000	2
2,250	2
2,500	2
3,000	3
3,500	3
4,000	4
4,500	4
5,000	5
5,500	5
6,000	6
7,000	7
8,000	8
9,000	9
10,000	10
11,000	10
13,000	10

 

The calculations of required fire flows in gallons per minute (GPM) considers the construction, occupancy, exposure and communication as outlined in the NFPA Fire Protection Handbook (latest edition).

(2)

Fire hydrants. Fire hydrants shall be installed according to the following requirements, with distances measured along street rights-of-way. No distance shall be measured across thoroughfares:

a.

In the case of a single-family or duplex residential development; one- or two-story motels, hotels, or multifamily dwellings, or mobile home parks, hydrants shall be installed at intervals not to exceed 500 feet with a minimum main size of six inches.

b.

In the case of a business or industrial development, excluding developments in a. above, hydrants shall be installed at intervals not to exceed 300 feet with a minimum main size of eight inches.

c.

In the case of a building which will provide standpipe and/or sprinkler systems, a fire hydrant shall be installed within 150 feet of the exterior fire department connection with a minimum main size of eight inches.

d.

In the case of the development of a high-hazard area including, without limitations, a large shopping center, a storage facility for flammable chemical or compressed gases or a manufacturing plant, the spacing and main sizes of hydrants shall be determined after computing the required fire flow, subject to review and approval by the department of fire services.

e.

All fire hydrants shall deliver the required gallonage with a residual pressure of 20 p.s.i.

f.

Uniform marking of fire hydrants. Color coding of fire hydrants is of substantial value to water and fire departments and is based on water flow available from them. Fire hydrant bonnets and nozzle caps shall be painted according to the following chart which shall be used to classify fire hydrants according to flow:

Class	Flow	Color of Bonnets and Nozzle Caps
A	1,500 GPM or greater	Blue
B	1,001 GPM or 1,499	Green
C	500 GPM to 1,000 GPM	Orange
D	Less than 500 GPM	Red

 

(3)

Fire wells.

a.

Fire wells may be utilized where permitted by subsection (1) of this section, providing they have a separate power source and meet one of the following criteria:

1.

The minimum size of a designated fire well shall not be less than six inches in diameter. A pump shall be attached capable of providing a minimum fire flow of 250 GPM; or

2.

A fire well four inches in diameter may be utilized provided that it has been tested and certified by an engineer that the fire well can produce a minimum fire flow of 250 GPM.

b.

Fire wells shall be located adjacent to rights-of-way, unless otherwise approved by the department of fire services and the DRC.

c.

Fire wells of sufficient capacity to serve adjacent development may be provided and, when so provided, may be included in a public services and facilities agreement pursuant to subsection 72-501(f).

d.

Fire wells shall be considered as public improvements subject to all provisions of division 5 of this article.

(Ord. No. 96-32, § XXVIII, 12-19-96; Ord. No. 2008-25, § III, 12-4-08)