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GeoTRIVIA December 2006
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The following GeoTrivia quiz questions appear in the December 2006 issue of OnLocation. What's your score?
- What are the minimum requirements for a fire hydrant to be a viable water source and contribute to a property receiving a better PPC™ classification?
- What is the reason for using 1,000 feet as the maximum requirement for the distance between the risk and a fire hydrant?
- Can a rural fire protection area without hydrants have a PPC better than 8B or 9?
- What percentage of the total amount of fresh water on earth makes up the Great Lakes?
- What is the largest water utility in the United States?
- What are the three longest rivers in the United States? The world?
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And the answers are…
- What are the minimum requirements for a fire hydrant to be a viable water source and contribute to a property receiving a better PPC classification?
| A review of a community's water-supply system accounts for 40 percent of the total PPC. Of that, 5 percent of the water-supply grade is based on hydrant size, type, and installation, as well as the inspection frequency and condition of fire hydrants.
The hydrant should be in working order and capable of delivering 250 gallons per minute (gpm) or more.
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A functioning fire hydrant
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A flush hydrant used to
flush water mains
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A nonfunctioning hydrant
for decorative purposes only
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Some fire hydrants appear to be functional and in good working order, but ISO and the fire department may not recognize them. Here are just a few reasons why a hydrant isn't recognized:
- inadequate flow
- system not connected
- flush hydrant not for firefighting
- no contract for its use
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- What is the reason for using 1,000 feet as the maximum requirement for the distance between the risk and a fire hydrant?
| The 1,000-foot distance for hydrant spacing is due to the amount of fire hose typically carried by most fire department pumpers for supply-line use. During on-site evaluations, ISO uses our Fire Suppression Rating Schedule (FSRS) to evaluate the amount, size, and type of fire hose carried by fire departments. |
A fire pumper at work with multiple hose lines of adequate length |
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The FSRS indicates that a standard load of 2.5-inch (or larger) hose is 1,200 feet. The FSRS credits up to 400 feet of 2.5-inch hose and up to an additional 800 feet of 2.5-inch or larger hose — for a total of 1,200 feet.
The 1,200 feet includes:
- 1,000 feet of supply hose to extend from the hydrant to the pumper at the risk
- 150 feet to use as an “attack”ť (discharge) line
- 50 feet to accommodate the snaking of the hose when it's laid out
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- Can a rural fire protection area without hydrants have a PPC better than 8B or 9?
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Yes. ISO may extend credit to rural areas without hydrants if they use the following alternative methods of water delivery:
- tanker-shuttle operations
- suction supply points
- large-diameter hose relays
- any combination of the above methods
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During a tanker-shuttle operation, a tanker drops a load of water in this portable drafting tank
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| ISO will credit those alternative water-supply methods if they can deliver a minimum of 250 gallons per minute for a two-hour duration.
For a tanker-shuttle operation, the operation must deliver at least 250 gallons per minute within five minutes of the arrival of the initial apparatus and maintain the flow for a two-hour duration. If the apparatus can increase the volume within the first 15 minutes of arrival and continue for the duration, ISO can credit the higher flow.
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- What percentage of the total amount of fresh water on earth makes up the Great Lakes?
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Twenty percent. The Great Lakes contain an estimated 5,500 cubic miles of water — a fifth of all the liquid surface fresh water on earth.
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- What is the largest water utility in the United States?
| Metropolitan Water District of Southern California is the largest water utility in the U.S. It's a consortium of 26 cities and water districts that serves almost 18 million people in Los Angeles, Orange, San Diego, Riverside, San Bernardino, and Ventura counties. Metropolitan delivers an average of 1.7 billion gallons of water per day to a 5,200-square-mile service area. |
- What are the three longest rivers in the United States? The world?
The United States
It's not easy to define how long a river is. If a number of tributaries merge to form a larger river, it's sometimes hard to determine where the river actually begins. The United States Geological Survey defines river length as the distance from the source to the mouth.
Longest rivers in the United States:
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Missouri
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 2,540 miles |
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Mississippi
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 2,340 miles |
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Yukon
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 1,980 miles |
The world
Estimates for the length of the world's rivers vary depending on season of the year, who's doing the measuring, and the capabilities of the cartographer. However, the biggest reason for different measurements is whether you include or exclude tributaries. Here, we've excluded the major tributaries.
Longest rivers in the world:
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Nile (Africa)
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 4,132 miles |
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Amazon (South America)
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 4,000 miles |
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Yangtze (Asia)
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 3,915 miles |
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