Description: This layer contains all Water Control Valves. Control valves are a set of valves that operate in special ways. There are three fundamental types of control valves: backflow control, air control, and altitude. A backflow control valve is a control valve designed to prevent water from flowing in the reverse direction. Essentially, backflow control valves allow flow in only one direction—the normal flow dirrection. Backflow control valves are open in the direction of normal flow and closed with the reversal of flow. Backflow control valves are commonly found near pump stations and reservoirs. Air control valves are control valves that are used to either relieve the system of trapped air or vacuums that may develop. Finally, an altitude valve is a control valve that controls water flow into a tower when the water level drops below a threshold. Altitude valves automatically shut off water flow when the water level in an elevated tank (or tower) reaches a preset elevation. A pressure reducing valve is a system valve with a horizontal disk for automatically reducing water pressures to a preset value. A pressure relief valve is a system valve that opens automatically when water pressure reaches a preset limit to relieve stress on a pipeline. Pressure relief valves are used to protect against rapid increases in pressure (i.e., water hammer). A pressure sustaining valve is a system valve that automatically sustains water pressures at a preset value. A pressure sustaining valve is similar to a pressure reducing valve but governs the pressure on the upstream rather than the downstream flow.Types of control valves represented include AirGap, AirControl, AirRelease, Altitude, BackflowControl, Combination, AtmosphericVacuum, DoubleCheck, PressureVacuum, ReducedPressureBackflow, RPZ, SimpleCheck, Vacuum, VacuumBreaker, and VacuumRelease.
Description: The Fitting class represents the facility found at the joint between two lines where a transition of some sort must occur. In order to cut down on the number of network feature classes and improve geometric network performance, we have chosen to rely on subtypes here to differentiate the different types of fitting-related classes. Fitting types include Bend, Cap, Cross, Coupling, ExpansionJoint, Offset, Reducer, Riser, Saddle, Sleeve, Tap, Tee, Wye, and Weld.
Description: A hydrant enables fire fighters to attach fire hoses to the distribution network. Hydrants also have secondary uses that include flushing main lines and laterals, filling tank trucks, and providing a temporary water source for construction jobs
Description: A pump is a facility that moves, compresses, or alters the pressure of a fluid, such as water or air, being conveyed through a natural or artificial channel. Pumps are also much like hydrants and meters Pump types include AxialFlow, Centrifugal, Jet, Reciprocating, Rotary, Screw, and Turbine.
Description: The SCADA sensor is a feature that’s used to remotely measure the status of network components as part of a supervisory control and data acquisition (SCADA) system. SCADA systems provide alarms, responses, data acquisition, and control for collection and distribution systems. Operators use the SCADA system to monitor and adjust processes and facilities.
Description: A system valve is a facility that is fitted to a pipeline or orifice in which the closure member is either rotated or moved transversely or longitudinally in the waterway so as to control or stop the flow. System valves are used to regulate pressure, isolate, throttle flow, revent backflow, and relieve pressure. System valve types include Gate, Plug, Ball, Cone, and Butterfly. These specific types may be classified as isolation valves. Isolation valves are designed to start and stop the flow of water within the distribution network (and isolate portions of the network for maintenance or repair). Isolation valves are the predominant type of SystemValve installed in a distribution network. They are commonly intended to be either fully open or fully closed. They are not intended to throttle flow by being partially open.A gate valve is an isolation valve (which is modeled here as a system valve) that is used to prevent water flow via a simple gate mechanism. Gate valves may be motorized (and remotely controlled), and they may also have small bypass valves. Gate valves are not installed in locations where they need to be frequently operated due to the time required to open and close them. A butterfly valve is similar to a gate valve but uses a disk that is rotated ninety degrees to control the flow of water. Butterfly valves operate easier underlarge pressures and volumes of water than standard gate valves, and are thus found on larger pipes. However, because the butterfly valve disk stays in the water path even when the valve is open, the valve creates a higher resistance to flow (i.e., pressure loss) than a gate valve. Additionally, if it becomes necessary to clean a main by using pigs or swabs, the butterfly valve would block the operation. Butterfly valves can be operated quickly, increasing the risk of serious water hammer.
Description: A sampling station is a facility that is used for collecting water samples. Sampling stations may be dedicated sampling devices, or they may be other devices of the system where a sample may be obtained.
Description: A lateral line is a small-diameter pipe that runs from the main to the customer premises. The Types of lateral lines are; DomesticFireCommercialIrrigationIndustrialHydrantLine
Description: A pressurized main is a type of main line that is pressurized. PressurizedMain is a concrete class. There are numerous types of PressurizedMains in the water distribution model; they include AirRelease, BlowOff, Bypass, ChemicalInjection, DistributionMain, Interconnect, ipeBridge, SamplingStation, and TransmissionMain. Transmission mains are large-diameter pipelines (24" or larger) that carry large quantities of raw water long distances from their source to a water treatment plant, then to the distribution grid system. Transmission mains generally run in a rather straight line from point to point. Lateral lines are not attached to transmission mains. Distribution mains are average-diameter pipes (4"–20") that transport potable water from transmission lines and redistribute it throughout an area. Lateral lines attach directly to distribution mains.
Description: A junction in the network that represents a significant facility such as a treatment plant, Production Well, resivoir or pump station. Usually contains many other pieces of equipment
Description: A pressure zone is defined as the area bounded by both a lower and upper elevation, all of which receives water from a given hydraulic grade line (HGL) or pressure from a set water surface. The HGL is usually provided by one or more storage tanks located at the same elevations so they share high and low water surfaces. Ideally, pressure zones contain the same pressures and, therefore, the infrastructure within each pressure zone can be designed with a uniform set of design criteria which stresses efficiency, reliability and durability.