Water distribution grades 3 & 4

what is the net positive suction head available given the following data? will the pump cavitate if the net positive suction head required is 18.4 ft 1.11 ft/in = Hg atmospheric pressure = 29.8in Hg static suction lift = 15.1ft friction head loss = 0.6ft vapor pressure at 12 degrees F = 0.50ft

17ft

what is the commonly accepted water velocity in water mains at a maximum flow?

2-4 ft (sec(0.6-1.2 m/sec))

how many times higher than the normal operation pressure should the pressure rating of distribution system piping be?

2.5-4.0 times

how many gallons per minute should a flowmeter register if a 10.0 in diameter main is to be flushed at 5.10 ft/sec

1.250 gpm

what is the maximum contaminant levels for arsenic

10 micrometers/L

a storage tank has a capacity of 34.0ft. currently there are 22.89ft of water in the tank. what would the scada reading be on the board in milliamps (mA) for a 4 mA to 20-mA signal?

14.8 mA

according to the us environmental protection agency's primary drinking water standards, what is the maximum contaminant level for alpha particles

15 pCi/L

according to the us environmental protection agency's primary drinking water standards, what is the maximum contaminant level goal for copper

3 mg/L

what is the motor horsepower, if 200 horsepower is required to run a pump with a motor efficacy of 88% and a pump efficacy of 74%

310 mhp

a tank 84.0ft in diameter and 24.25ft high at the overflow requires disinfection. how much 12.5% sodium hypochlorite that is 9.59 lb/gal will be requied for a dosage of 50.0 mg/L?

350 gal

water systems are required to achieve at least (blank) removal and inactivation of viruses between a point where the raw water is not subject to recontamination by surface water runoff and a point downstream before or at the first customer

4 log

a well that is 210ft in depth and 14.0in in diameter requires disinfection. the depth to water from the top of the casing is 91ft. if the designed dose is 50.0 mg/L, what is the number of pounds and ounces of sodium hypochlorite

43 oz of NaOCl

when converting from US pipe sizes, what is considered the metric equivalent of 0.25 in?

8 mm

automatic control

a system in which equipment is controlled entirely by machines or computers without human intervention under normal conditions

scanning

a technique of checking the value of each of several instruments, one after another. used to monitor more than one instrument over a single channel

polling

a technique of monitoring several instruments over a single communications channel with a receiver that periodically asks each instrument to send current status

pulse-duration modulation

a telemetry-signaling protocol in which the time that a signal pulse remains on varies with the value of the parameter being measured

remote manual control

a type of system control in which personnel in a central location manually operate the switches and levers to control equipment at a distant site

direct manual control

a type of system control in which personnel manually operate the switches and levers to control equipment from the physical location of the equipment

duplexing

a type of telemetry in which a single line allows the operator to send the instrument signals that are received at the central location back to a remote site

rural water system

a water system that has been established to se3rve widely spaced homes and communities in areas having no available water of very poor quality

purchased water system

a water system that purchases water from another water system and so generally provides only distribution and minimal treatment

groundwater system

a water system using wells, springs, or infiltration galleries as its source of supply

head loss

amount of energy used by water in moving from one location to another

relay

an electrical device in which an input signal, usually of low power, is used to operate a switch that controls another circuit, often of higher power.

solenoid

an electrical device that consist of a coil of wire wrapped around a moveable iron core. when a current is passed through the coil, the core moves, activating mechanical levers or switches.

piezometric surface

an imaginary surface to which groundwater rises under hydrostatic pressure, to produce springs

proportional control

automatic control in which a valve or motor is activated slightly to respond to small variations in the system, but activated at a greater rate to respond to larger variations

Per-capita water use

average day demand divided by number of residents connected to the water system.

how is the wire-to-water efficiency obtained

by multiplying the motor and pump efficiencies together

what is the formula for calculating chlorine demands

chlorine demand(mg/L) + chlorine residual(mg/L) = chlorine dosage(mg/L)

analog

continuously variable, as applied to signals, instruments, or controls

the (blank) is the outlet or high pressure, side of a pump

discharge side

grid systems

distribution system layout in which all ends of the mains are connected to eliminate dead ends

arterial loop system

distribution system layout involving a complete loop of arterial mains around the area being served with branched mains protecting inward, such a systems minimizes dead ends

tree system

distribution system layout that centers around a single arterial main, which decreases in size with length. branches are taken off at right angles, with subbranches from each branch

what is the formula to convert milligrams per liter concentration to pounds per day

feed rate (dosage) (flowrate) (conversion factor)

the size and capacity of a water distribution system is based largely on?

fire demand

in what type of water distribution layout are all ends of the mains connected to eliminate deadends?

grid system

what type of water systems uses wells, springs, or infiltration galleries as its source of supply?

ground water system

what is the term for the amount of energy used by water in moving from one location to another

head loss

friction head loss

head lost by water flowing in a stream or conduct as a result of disturbance set up by the contact between the moving water and its containing conduct and intermolecular friction

secondary instrumentation

instruments that respond to and display information form primary instruments

what is the term for the water use during the 24 hours of highest demand during the year?

maximum day demand

what term refers to the highest level of disinfectant allowed in drinking water

maximum residual disinfectant level

disinfection by-products (DBPs)

new chemical compounds that are formed by the reaction of disinfectants with organic compounds in water. At high concentrations many DBPs are considered a danger to human health

if a water system collects at least 40 samples per month for there analyses of total coliforms, what percentage of total coliform positive samples are acceptable for the system to remain in compliance with the maximum contaminant level for total coliforms?

no more than 5%

continuous chlorine residual monitoring is required where the water enters the distribution system under the surface water treatment rule when the

population served is >3,300 people

which of the following is the most common cause for surges in the distribution system

power failure shutting down a pump suddenly

Static Pressure

pressure that exists in water although the water does not flow

Fire flow

the rate of flow usually measured in gallons per minute(gpm) or liters per minute(L/min) that can be delivered from a water distribution system at a specified residual pressure for firefighting. when delivery is to fire depts. pumpers are specified residual pressure is generally 20psi (140 Kpa)

WIRE-TO-WATER EFFICIENCY

the ratio of the total power input to a motor and pump assembly, to the power output expressed as a percent, the combined efficiency of the pump and motor

control terminal unit

the receiver in a digital signal system

Velocity

the speed at which water moves, measured in ft/sec or m/sec

total static head

the total height that the pump must lift the water when moving it from one point to another, the vertical distance from the suction free water surface

average day demand

the total system water use for 1 year divided by 365 days in a year.

a water system using conventional filtration treatment does not have to use enhanced coagulation to achieve the total organic carbon (TOC) percent removal if?

the treated water quarterly running average TOC is less than 2.0 mg/l

Maximum day demand

the water during the 24 hours of highest demand during the year

A regulated organic contaminant concentration that exceeds the MCL

tier 2 violation requiring public notification with 30 days

regarding fire flow, mains smaller that 6 in (150 mm) should be used only

to a complete a grid

what are the basic components of every telemetry system?

transmitter, transmission channel, and receiver

A(n) (blank) layout centers around a single arterial main, which decreases in size with length

tree system

digital

varying in precise steps as applied to signals or instrumentation and control devices

surface water systems

water that is located atop Earth's surface (river, lakes, soil moisture, atmospheric water vapor)

on-off differential control

A mode of controlling equipment in which the equipment is turned fully on when a measured parameter reaches a preset value, then turned fully off when it returns to another preset value.

Surge pressure

A momentary increase of water pressure in a pipeline due to a sudden change in water velocity or direction of flow

pump center line

An imaginary line through the center of a pump

The pressure during fireflow conditions should not drop below?

B. 20 psi (138 KPa)

what is plotted on the horizontal scale(x-axis) of a pump curve?

Capacity (flow rate)

What type of distribution system configuration has smaller mains that generally terminate as deadends?

D. Tree system

Hydrostatic Pressure

Pressure exerted by water at rest

Dynamic Pressure

Pressure that exists in water as moving energy

what is the formula for calculating the quantity of water that flows through a pipe?

Q= A x V or quantity of water= cross sectional area of pipe x velocity of flow

variable frequency

Relating to a type of telemetry signal in which the frequency of the signal varies as the parameter being monitored varies.

regulations that govern US water supply and treatment are developed by the US environment protection agency under which act?

Safe drinking water act

dynamic suction head

The energy head available on the inlet side of a pumping system, reduced from the static suction head by the amount of friction and minor losses.

Water Hammer

The potentially damaging slam, bang, or shudder that occurs in a pipe when a sudden change in water velocity (usually as a result of someone too-rapidly starting a pump or operating a valve) creates a great increase in water pressure.

direct-wire control

a system for controlling equipment at a site by running wires from the equipment to the onsite control panel

pump characteristic curve

a curve or curves showing the interaction of speed, dynamic head, capacity, brake, horsepower, and efficiency of a pump

instantaneous flow rate

a flow rate of water measured at once particular instant, such as by a metering device involving the cross sectional area of the channel pipe and the velocity of the water at that instant

semiautomatic control

a form of a system control equipment in which many actions are taken automatically but some situations require human intervention, under normal conditions

voltage

a measure of electrical potential / in telemetry, a type of signal in which the electromotive force varies as the parameter being measured varies

supervisory control and data acquisition

a methodology involving equipment that both acquires data on an operation and provides limited to total control of equipment in response to the data

what type of water system is established to serve widely spaced homes and communities in areas having no available ground water or having very poor quality?

rural water system

dynamic water system

the description of a water system when water is moving through the system

static water system

the description of a water system when water is not moving through the system

static suction lift

the difference in elevation between the pump center line of a pump and the free water surface of the liquid being pumped in a static suction lift measurement, the piezometric surface of the water at the suction side of the bump is lower than th pump, otherwise static suction head is measured

dynamic discharge head

the difference in height from the pump center line a the pump discharge to the point on the HGL directly above it

minor head loss

the energy losses that result from the resistance to flow as water passes through valves, fittings, inlets, and outlets of a piping system

current

the flow rate of electricity measure in amperes / in telemetry, a signal whose amperage varies as a parameter being measured varies

pressure

the force on a unit area of water

Peak hour demand

the greatest volume of water in an hour that must be supplied by a water system during any particular time period, such as a year to meet customer demand

suction side

the inlet or low-pressure side of a pump

Maximum contaminant level (MCL)

the maximum permissible level of a contaminant in water as specified in the regulations of the Safe Drinking Water Act

power in hydraulics or electricity

the measure of the amount of work done in a given period of time, the rate of doing work measured in watts or horsepower

work

the operation of a force over a specific distance

discharge side

the outlet or high pressure side of a pump

receiver

the part of a meter that converts the signal from the sensor into a form that can be read by the operator, also called the receiver-indicator / in a telemetry system the device that converts the signal from the transmission channel into a form that the indicator can respond to

indicator

the part of an instrument that displays information about a system being monitored, generally either an analog or digital display