BY ERIC G. BACHMAN
Although fire departments may have varying types and quantities of equipment, operational policies, standard operating procedures, and staffing, all—large and small, volunteer and career—must depend on a water supply to protect their jurisdiction and their customers, who expect a competent and an efficient response when they have emergencies.
This fact is no surprise! What is surprising, however, is that some departments do not make a concerted effort to identify, maintain, practice, and refine water supply and delivery operations. Do not think that this article applies only to rural fire departments whose communities lack a water supply infrastructure. It applies to all departments.
The water delivery formula consists of three components: a water source, delivery mediums, and application mechanisms. Although it is easy to say, it is often challenging to execute. The diversity of source types, abilities to tap them, and the intricacies of moving and applying water are not the same for every jurisdiction.
Preparations for an evolution should include contingencies. Sometimes, fire departments with a community water supply system become complacent, thinking that water will always flow from the fire hydrant. That mindset, combined with Murphy’s Law (where anything that can go wrong will go wrong—and at the worst possible time) is a recipe for disaster. You must have a Plan B before you need one.
The only absolute the fire service can count on is that there are no absolutes. Fire department leaders must constantly prepare for what can happen and what may happen. Preincident preparedness is a full-circle process that never ends. Concentrated efforts are necessary as much for water source dispositions as they are for structural hazard intelligence.
NEEDED FIRE FLOW
To effectively extinguish a fire, the fire department must have an understanding of how much water may be needed. The Needed Fire Flow (NFF) calculation, advocated by the National Fire Academy (NFA), is a simple formula you can use to quickly estimate the gallons per minute (gpm) needed when no other preincident information is available. It can also be referenced during preincident preparation activities to formulate equipment and personnel needs.
The NFA formula multiplies the length times the width of a structure and then divides by three (L × W ÷ 3). The resulting figure represents the needed fire flow, in gpm, if 100 percent of the structure is involved. The figure can be adjusted according to the level of fire involvement. Additional calculations are necessary for multistoried buildings as well as for exterior exposures. Use the NFF formula as a guide for water delivery needs. What the calculation does not and cannot determine is the duration of the flow needed. Extinguishment is not solely about quantity of water available but also the effectiveness of its application.
Other formulas have been developed by other entities; you should study them for their application within a preincident preparedness program. One formula is the Iowa Rate of Flow Formula for Fire Control. For this calculation, “the cubic feet divided by 100 equals the gallons per minute necessary to knock down a fire in an area if that flow is properly distributed over the entire area.”1
Another calculation is part of the Insurance Services Office (ISO) Fire Suppression Rating Schedule. It prescribes an NFF formula that includes other structural characteristics and exposure information. The formula is more complicated; it is recommended that firefighters study the Fire Suppression Rating Schedule and refer any specific questions to the ISO.
A third source to aid in water supply calculations is the NFA online course Q217—Alternative Water Supply: Planning and Implementing Programs. This program is free to the fire service.2
A critical facet of each calculation is that it focuses on incidents occurring in the built environment. Sustaining a water supply is essential. But most structure fires are not campaign events and typically do not necessitate high fire flows for extended periods of time. Nonstructure fire incidents, however, may necessitate water supply application outside the scope of typical fire flow calculations. A hazardous materials incident, flame impingement on compressed or liquefied gas tanks, as well as a host of other scenarios may need an extraordinary water supply and application to control or prevent an incident from escalating.
In December 2003, a fire at a Pennsylvania propane distribution facility3 tested the fire department’s water supply and sustainment capabilities. The fire department applied water onto the numerous exposed tanks to prevent a boiling-liquid, expanding-vapor explosion and to cover other exposures. The six-hour firefight used more than 720,000 gallons of water. The entire operation relied on mobile water-tender shuttles because there was no water supply infrastructure.
WATER SOURCE IDENTIFICATION
Identifying water supplies is important, and most fire departments know the water supply venues in their districts. Typically, sources are noted on a list or a map kept in the fire apparatus; in other cases, the data are maintained in apparatus-borne laptops. Unfortunately, some departments do not have any database whatsoever other than the material members remember as they drive down the street.
You can use many methods to identify water sources. Physical marking programs, such as installing a physical marker (photo 1), is beneficial for directing mutual-aid companies to water source sites, especially for departments that may be unfamiliar with the area. A sign or other identifier does not constitute comprehensive water source intelligence. Water sources, including hydrant systems, are not the same. Each water source has limitations that are not universal. Some are more accessible than others. Photo 2 illustrates a predetermined water source. Fire apparatus, however, have to cross active railroad tracks to access it.
|(1) Photos by author.|
Supply capabilities vary as well. Some are essentially endless, such as the sites in photos 3-4, which are designated as “Dry Hydrants” at a marina along the Chesapeake Bay. Others, such as a cistern, may provide a limited supply.
WATER SOURCE INTELLIGENCE
No two water sources are the same. Each can present challenges that, if not anticipated, can have significant influence on the incident outcome. Capability and reliability are two of the most common factors that present challenges with a water source.4 Both apply not to just rural settings but also to urban areas supported by hydrants.
Not all hydrants provide the same flows. Dead-end hydrants, piping, and outlet factors can alter flow values. When discussing water delivery, drafting operations, and mobile water shuttles, firefighters in departments with water supply infrastructure often lose interest. This complacency, however, will lead to unpreparedness when the well runs dry, so to speak. Regardless of the district disposition, you must be thorough in identifying water sources.
ANYTHING CAN HAPPEN
Anything can happen anywhere. In November 2005 in Pennsylvania, a railcar of highly flammable pentane was leaking in a rail yard. Although the rail yard is within the city limits, the municipal water system does not service it. Laying a supply line from the nearest hydrant was not feasible. Mutual aid was initiated using volunteer county departments to establish a “rural” water supply system using portable tanks and mobile water tenders.
In April 2010, in Pennsylvania, crews were dispatched to an apartment building fire with occupants reported trapped. First-arriving units found heavy fire conditions on the top floor. Water supply efforts, however, were hampered because of a water main break. Mobile water tenders were called to the scene to assist.
Preparing for contingencies is a mainstay of the fire service. Risk-based response, structured alarms, and rapid intervention crews are examples of how the fire service prepares for certain contingencies. Apply that same mindset to water sources. Too many things can go wrong at an incident; one of them should not be failure to have the most basic of resources, water. The availability of a water source is not a given. Even in an urban setting with hydrants, the water source may become inaccessible because of weather conditions or construction projects. A hydrant may be too close to the incident, making crews and apparatus fire exposures. Also, the water source may be inadequate for extraordinary situations, exhausted, or otherwise out of service.
Fire departments should analyze their water supplies and develop and practice accessing and delivering water from contingent sources. Another factor that can contribute to water supply problems is failing to share water supply intelligence information with automatic- or mutual-aid companies. Fire service leaders must go outside the water source “ownership” box. Local and regional cooperative efforts in identifying, delivering, and applying water are essential.
Lancaster County, Pennsylvania, is a diverse county made up of 60 municipalities protected by 80 independent fire departments. One department is career, three others (within one township) share part-time personnel, and the remainder are all-volunteer.
In the early days of its fire service, the county was divided into zones, and station numbers were assigned to each fire station within each zone. Zone 4, made up of nine independent volunteer fire companies, protects the central eastern portion of the county. Its jurisdiction includes the site of the propane incident mentioned above. Collectively, the protected area is 94 square miles with 25,400 permanent residents. Well-known for its Amish heritage, this area is home to small villages with unique names such as Bird-In-Hand, Gap, and Paradise. But as unique as this area is, the fire departments that protect it are no different from those in any other location. They, too, are experiencing staffing and funding issues along with ever-increasing response demands.
They also share limitations in water sources, since most of the area is not supported by water supply infrastructure. For several years, and especially since the 2003 propane incident, a committee representing almost all the Zone 4 departments has cooperatively worked on developing and enhancing water supply efforts. The departments frequently practice water supply operations, aspiring to sustain certain flows.
WATER SOURCE MANUAL
This group has taken water source intelligence to a new level. It was not satisfied with only identifying water source locations; collectively, there are more than 100 preidentified sites. The member departments comprehensively analyzed the intricacies of each site and published a manual (photo 5) that defines capabilities, limitations, and other operational considerations. By studying this manual before an incident occurs, fire officers can evaluate the capability of each site and assess the availability of adequate fire flows for specific incidents. This manual also allows fire officers to prescribe resources that are most effective for initiating drafting operations at each site.
The manual is arranged by jurisdiction, and each source is assigned an identifier. A photograph of each specific location information, including address and cross-street information, is included. Additional operational data are listed specific to the site’s orientation, arrangement, type, capacity, and use. Photo 6 shows a typical page in the manual with the site photo and specific data.
Natural and man-made sources are identified. Natural sources include ponds, springs, and streams. Man-made sources include cisterns (photo 7), hydrants, quarries, storm-water basins, a storm-water basin equipped with a dry hydrant (photo 8), pools, and sources with a dry hydrant assembly (photo 9, a dry hydrant installed at a pond). Specific considerations are offered to maximize the capability and use of each site.
Accessibility is one of the most important factors. Some sites are accessible next to the road edge; drafting operations can be initiated from a bridge (photo 10), allowing fire apparatus to deploy drafting equipment easily. Other sites are in fields and pastures or can be reached only by traveling unpaved paths that may require four-wheel-drive capabilities. Other constraints may influence approach and positioning at a site. In certain situations, the specific side of the road or bridge best suited to facilitate drafting operations is noted. For others, apparatus may not be able to parallel a site. An engine company with a bumper-mounted pump that can nose into a site may be advantageous (photo 11). Appropriate approach and positioning directions are also offered with regard to specific obstacles including utility poles, trees, fences, and mailboxes. For one site, the best approach is explained as “from the north and then swing wide.”
Efficient water supply hinges on effective deployment of support equipment. Supply hose, manifolds, portable tanks, and other mediums can affect a water supply operation. In some cases, space is limited, and placement of the aforementioned items can be critical to the efficiency of the operation. Distances and other potentially hampering conditions are noted to make the best of compromised situations.
Conditions that may necessitate operational support have also been anticipated such as how many hard-suction sleeves may be needed. Most sites require two sleeves. Others need as many as three sections; for one site, four sections are necessary. This is an important factor for assigning apparatus with adequate support equipment. Many pumper and initial attack fire apparatus carry the National Fire Protection Association 1901, Standard for Automotive Fire Apparatus, 2009 edition, minimum of 20 feet (typically two sleeves) of suction hose. Therefore, in the case of the site that needs four sleeves, two pumpers would have to be committed to complete a drafting operation. Resource specifications for ancillary equipment (in addition to the pump and water tank capacity) should also be addressed.
For some sources, the available supply of water fluctuates. Open sources, such as streams and ponds, can be affected by extreme weather conditions. The winter season may cause sources to freeze over, and snowfall could prohibit accessibility to a site. Sweltering heat conditions could facilitate drought conditions and affect the water table to the point where already fragile supplies are reduced below the level at which they can be used. There can be other restraints as well: One private water source is not available during the fishing season.
“Closed” systems, such as cisterns, may have varied capacities. The cisterns identified in the Zone 4 Manual include public and private sites. One public venue is in the center of a small village; others are at fire stations. There is also a private cistern on the premises of a local market. The capacity of cisterns ranges from 17,000 gallons to 85,000 gallons.
It may be necessary to consider other source-specific issues as well—not all can be mentioned here. One important issue, however, is obtaining permission to use the source. Before the incidents occur, obtain written permission to use the water source during emergencies. Not all water source owners will agree to the use—for example, one site in the manual can be used only for fires on the property on which it is located.
In some cases, site enhancements may be necessary to maximize the effectiveness of the water source. In one case, the stream in front of the installed standpipe must be dammed with plywood. To facilitate this, the property owner has filled a shed near the dry hydrant with plywood for the damming evolution.
This manual has enhanced the Zone 4 companies’ service to the community. It has also become a catalyst for improving fire protection services on a much larger scale: The Lancaster Countywide Communications (county 911) Center is working with other county fire departments to identify viable water sources and plot them within the county’s Geographical Information System. This will benefit Zone 4’s neighboring fire districts.
A uniform method of identifying these sites by signs is under consideration. A few of the sites in Zone 4 have a marker or a sign. In other zones, some companies have installed designated draft site markers. There is no countywide marking system.
Fire departments respond to emergency situations at a moment’s notice. The public expects that they will fix the problem in an effective and efficient manner. To be able to do this, fire departments must have an adequate supply of water. Yet some departments are not aggressive in identifying, practicing, and improving their water delivery capabilities. Regardless of whether you initially depend on water from a hydrant or a pond, contingencies are necessary because anything can happen anywhere. An effective water supply not only protects the public and saves property, but it protects us as well.
1. http://www.fireengineering.com/articles/print/volume-148/issue-9/features/iowa-rate-of-flow-formula-for-fire-control.html. “Water for Firefighting–Rate of Flow Formula,” Iowa State University Bulletin #18, 1959.
2. The program is available at http://www.usfa.fema.gov/nfa/nfaonline/browse/fireprev_tech.shtm#Q217.
3. “Propane Explosion: A Case Study,” Fire Engineering, March 2005.
4. “Water Supply Preincident Intelligence,” Fire Engineering, October 2005.
ERIC G. BACHMAN, CFPS, a 29-year veteran of the fire service, is former chief of the Eden Volunteer Fire/Rescue Department in Lancaster County, Pennsylvania. He is the hazardous materials administrator for the County of Lancaster Emergency Management Agency and serves on the Local Emergency Planning Committee of Lancaster County. He is registered with the National Board on Fire Service Professional Qualifications as a fire officer IV, fire instructor III, hazardous materials technician, and hazardous materials incident commander. He has an associate degree in fire science and earned professional certification in emergency management through the state of Pennsylvania. He is also a volunteer firefighter with the West Hempfield (PA) Fire & Rescue Co.