Water Utilities Flashcards
what do water supply systems do?
supply water to distribution systems
what type of distribution systems are there?
gravity pump or combination of both
elevation of 100ft will create how much pressure?
43psi (.433 per ft of elevation )
where do gravity systems get their supply?
lakes and reservoirs
when are pumps used ?
when water source are at or below municipality?
what type of system is Los Angeles ?
Combination system supplies 600 million gallons a day
what does the Los Angeles Distribution system consist of ?
pipes
valves
check valves
water meters
how are pipelines in distribution systems classified
trunk lines, mains, service and customer lines
what are trunk lines?
they carry water from source to mains
what size are trunk lines?
36 inches to 10 ft and can made iron or concrete
what are main lines?
run beneath street and parallel to curb vary 2 to 72 inches in size made of iron pipe
why do mains cross connect
to form loops that allow shutting down specific main for repairs
what are service lines?
run between main and water meter can vary 1/2 inch to 12 inches can be iron, copper, or galvanized beer
what are customer lines?
run between water meter and structure 1/2 inch to 12 inches can be iron, copper, galvanized, or plastic pipe
what are water water utilities companies are normally responsible for maintenance and repair of water distribution system including:
water metering device
shut off valves on either side of meter device
What are building owner responsible for maintenance and repair?
plumbing from shut off valve on the output side
all plumbing inside the structure
what are water service system consist of ?
shut off valve
water meters
detector check valves
pressure reducing valves
what are shut off valves?
provides mean for controlling the flow of water through service and customer lines
what kind of shut off valves do you have?
non indicating valves; ball cone and gate valves that have rectangular nut on top of valve. valve is closed when perpendicular
Indicating valves
outside stem and yoke and post indicator valves
what are water meter and check valves ?
meters calculate water usage vary in size 1/2 inch to 10 inch, check valves allow flow of water in one direction only
what are compound meters ?
for domestic water usage that use high and low water flows.
during high flows a check valve opens and allows large flows that are metered separately
they’re usually 4 inches or larger
what are detector check valves?
open allows water to flow straight through unmetered
closed prevents water to flow back to distribution system(FD pumping to standpipes)
water service for domestic water and fire protectional located where ?
separate below ground vaults or located above ground
where are shut off normally located ?
Adjacent to water meters in separate vaults ir single mete that serves an entire building
