Ch.2 Water Supplies Flashcards
Under extreme circumstances the fire department can boost system pressure by pumping back into a hydrant.
False
The maximum space between Hydrants in a residential area is
meters.
300 meters
Water services designed the grid system to supply water for commercial, residential and firefighting. What percent is intended for commercial and residential combined?
20%. The remaining 80% is the required capacity that must be available for firefighting purposes.
To achieve the required fire flow water services allows the use of how many hydrants?
3 hydrants that are closest
The city of Calgary has how many pressure zones?
47 Zones
What is the minimum residual water pressure to be maintained in city hydrants?
140 kpa or 20 psi
What is the minimum design hydrant flow?
5000 LPM or 1320 US GPM
What are the color coding of hydrants in the city?
Purple - more than 12,500 LPM
Blue - 10,000 - 12,500 LPM
Green - 7,500 - 9,999 LPM
Yellow - 5,000 - 7,499 LPM
Red - less than 5,000
What does a hydrant with a “Main Controlled” ring on the 125mm port mean?
These hydrants are on feeder mains where the valves are either partially closed, or a limited amount of valves are open.
Can we call water services to have the water pressure increased to meet our demands during a call?
Of the city’s 47 pressure zones, only 7 are pressure fed. These zones could have their pressure increased by water services (limited to 150 psi).
What water plant supplies the north sector of Calgary?
The Bearspaw Plant
What water plant supplies the south sector of Calgary?
The Glenmore Plant
If additional hydrants are required for a very large multiple alarm fire, how should the next hydrant be selected?
If the first hydrant is on a dead end main, the second hydrant would ideally be on a different main with at least one cross main (the larger the better).
If the first hydrant is on a fully connected grid system (most areas of downtown), the second hydrant need only be 2 blocks away to have minimal impact on the initial water supply.
Will the use of a hydrant from a different pressure zone eliminate any change in flow to the initial hydrant in a pressure zone?
The majority of pressure zones are interdependent and one pressure zone will feed into the next. A hydrant in a separate pressure zone may still impact the flow of the initial hydrant.
Pressure zone boundaries will not be displayed on the MPS.
If a second hydrant is required for a large fire, the next closest high flow hydrant with at least one cross-connected main will always be the best choice, whether it is on the same pressure zone as the initial hydrant or not.
What is the hydrant spacing in industrial areas?
150 meters
