InfoSewer and InfoSWMM Nodes

InfoSewer and InfoSWMM Nodes

The different node types in InfoSewer and InfoSWMM reflect the distinct characteristics and purposes of sanitary sewer and stormwater/watershed modeling, respectively. Let's break down the node types in more detail based on your description and the implied image:

InfoSewer Node Types (1-4)

• Type 1: Loading Manhole:

  • Purpose: Represents a point where wastewater flow enters the sanitary sewer system. This is where you'd typically define inflows from residential, commercial, or industrial sources.
  • Characteristics:
    • Receives external inflow (dry weather flow, I&I, etc.).
    • May or may not have an invert elevation (bottom of the manhole). The invert elevation is important if you want to model the overflow of the manhole and the interaction with a relief sewer.
    • Typically connected to gravity sewer pipes (links).
    • Has various parameters like area, population, flow patterns, etc., to define the wastewater loading.

• Type 2: Junction (Non-Loading):

  • Purpose: Represents a simple connection point between two or more gravity sewer pipes where no significant external inflow is added.
  • Characteristics:
    • Primarily serves to connect links and maintain hydraulic continuity.
    • Does not receive external inflow (or has negligible inflow compared to loading manholes).
    • Has an invert elevation.

• Type 3 & 4: Wet Well/Chamber Junctions (Force Main Start/End):

  • Purpose: These nodes are specifically associated with force mains (pressurized pipes).
  • Type 3 (Wet Well): Represents the starting point of a force main. It typically receives flow from gravity sewers and is where a pump is located to lift the wastewater into the force main.
    • Has a volume-depth or area-depth relationship to simulate storage.
    • Associated with a pump curve to define the pump's operation.
  • Type 4 (Chamber Junction): Represents the end point of a force main, where the flow transitions back to a gravity sewer system. It also may have a volume-depth curve and an overflow weir option.
    • Often has a higher elevation than the downstream gravity sewer to provide a driving head.
  • Characteristics:
    • Crucial for modeling pump stations and the transition between gravity and pressurized flow.
    • Involve parameters related to pump operation, storage volume, and wet well dimensions.
    • In InfoSewer, a Wet Well is connected to a downstream Force Main by a discharge link.

InfoSWMM Node Types (5-8)

• Type 5: Junction:

  • Purpose: The most common node type in InfoSWMM, similar in function to InfoSewer's Type 2 junction. It connects links (conduits) in the drainage network.
  • Characteristics:
    • Represents manholes, inlets, or other connection points.
    • Has an invert elevation and a maximum depth.
    • Can receive inflows from subcatchments (surface runoff) or external flow time series.
    • The Junction can have a Ponded Area, Surcharge Depth, External Inflow and Treatment Functions,
    • A Junction can be connected to a Diversion Link with a user defined Diversion Table of Main Link Flow versus Diverted Flow.

• Type 6: Outfall:

  • Purpose: Represents the downstream end of the drainage system where flow is discharged to a receiving water body (e.g., river, lake, ocean).
  • Characteristics:
    • Defines the boundary condition for the system.
    • Can be a free outfall, or have a fixed or time-varying water surface elevation.
    • The Outfall can have a Ponded Area, External Inflow and Treatment Functions,

• Type 7: Flow Divider:

  • Purpose: Used to split flow into two or more downstream conduits based on defined rules.
  • Characteristics:
    • Allows for modeling of flow diversion structures.
    • Diversion can be based on flow rate, water depth, or a combination of factors defined in a diversion curve (similar to InfoSewer).
    • The Divider can have a Ponded Area, Surcharge Depth and External Inflow.

• Type 8: Storage Unit:

  • Purpose: Represents a storage facility within the drainage system, such as a detention pond, retention pond, or a large chamber.
  • Characteristics:
    • Defined by a stage-storage (or depth-area) relationship to represent its volume.
    • Can have an outlet structure (e.g., weir, orifice, pump) to control the release of stored water.
    • Important for modeling the attenuation of peak flows and reducing downstream flooding.
    • The Storage Unit can have a Ponded Area, Surcharge Depth, Evaporation and External Inflow.

Key Differences Summarized:

Feature	InfoSewer	InfoSWMM
Focus	Sanitary sewer systems (wastewater collection)	Stormwater, watersheds, drainage networks
Inflows	Primarily at loading manholes (dry weather flow)	Distributed across subcatchments (surface runoff) or at nodes
Pressurized Flow	Modeled using force mains and wet wells/chambers	Generally not modeled (unless using surcharge or RDII in InfoSWMM)
Storage	Primarily in wet wells	Detention/retention ponds, storage units
Outlets	Often pumps at wet wells	Weirs, orifices, culverts at storage units or outfalls
Diversions	Not as common, typically using pumps and force mains	More common, using flow divider nodes
Typical Node	Manhole (loading or non-loading)	Junction

Conclusion:

The different node types in InfoSewer and InfoSWMM reflect the specific needs of modeling sanitary sewer and stormwater systems, respectively. Understanding these node types and their characteristics is essential for building accurate and representative models in each software.