Load an EPANET .inp file into a named session.

Args: path: Absolute file path, relative path, or bare filename (e.g. "Net1.inp") searched in ePyT's bundled networks. network_id: Optional human-readable session identifier. Defaults to the file's base name without extension.

Returns: network_id, path, and a network summary (node/link counts, flow units, simulation duration).

Unload a previously loaded network and free its resources.

Args: network_id: The session id returned by load_network.

Return the ids of all currently loaded networks.

List every .inp example file bundled with ePyT (usable with load_network).

Return a high-level summary of a loaded network.

Includes node/link counts, flow units, simulation duration and hydraulic timestep.

Args: network_id: Session id of the network to inspect.

Return all nodes (junctions, tanks, reservoirs) with their attributes.

Attributes include elevation, base demand, and type. Tanks also include min/max/initial water levels and diameter.

Args: network_id: Session id of the network to inspect.

Return all links (pipes, pumps, valves) with their attributes.

Attributes include type, connected nodes, diameter, length, roughness coefficient, and minor loss coefficient.

Args: network_id: Session id of the network to inspect.

Return all demand / operational patterns defined in the network.

Args: network_id: Session id of the network to inspect.

Return all simple controls defined in the network.

Args: network_id: Session id of the network to inspect.

Return all curves (pump head, efficiency, volume, valve) in the network.

Args: network_id: Session id of the network to inspect.

Return simulation options: timesteps, units, quality settings, head-loss formula, and demand model.

Args: network_id: Session id of the network to inspect.

Run a full hydraulic simulation and return time-series results.

Returns pressures, demands, heads, flows, velocities, head-losses and link statuses at every reporting time step.

Args: network_id: Session id of the network to simulate.

Run a full water-quality simulation and return time-series results.

Includes node/link quality concentrations plus all hydraulic results. Configure the quality type first with set_quality_type.

Args: network_id: Session id of the network to simulate.

Run both hydraulic and water-quality simulations and return combined time-series results (pressures, flows, quality, reaction rates, etc.).

Args: network_id: Session id of the network to simulate.

Return node pressures at (or nearest to) a specific simulation time.

Args: network_id: Session id of the network. time_s: Simulation time in seconds (e.g. 3600 = 1 hour).

Return link flows at (or nearest to) a specific simulation time.

Args: network_id: Session id of the network. time_s: Simulation time in seconds.

Save the current (possibly modified) network to a new .inp file.

Args: network_id: Session id of the network to save. output_path: Destination file path (should end in .inp).

Set the base demand for a junction node.

Args: network_id: Session id. node_id: Junction node name/ID. demand: New base demand in the network's flow units. demand_category: Demand category index (default 1).

Overwrite all multiplier values for a named demand pattern.

Args: network_id: Session id. pattern_id: Name of an existing pattern. values: New list of multiplier values.

Add a new demand / operational pattern to the network.

Args: network_id: Session id. pattern_id: Unique name for the new pattern. values: Multiplier values for consecutive pattern time steps.

Set the diameter of a pipe.

Args: network_id: Session id. pipe_id: Pipe name/ID. diameter: New diameter in the network's length units (mm or inches).

Set the roughness coefficient of a pipe.

Args: network_id: Session id. pipe_id: Pipe name/ID. roughness: Hazen-Williams C factor (or Darcy-Weisbach roughness height).

Open or close a pipe.

Args: network_id: Session id. pipe_id: Pipe name/ID. status: "OPEN" or "CLOSED".

Set the length of a pipe.

Args: network_id: Session id. pipe_id: Pipe name/ID. length: New length in the network's length units (feet or metres).

Start or stop a pump.

Args: network_id: Session id. pump_id: Pump link name/ID. status: "OPEN" (running) or "CLOSED" (stopped).

Set the relative speed setting of a pump.

Args: network_id: Session id. pump_id: Pump link name/ID. speed: Speed ratio (1.0 = design speed, 0.5 = half speed).

Set (replace) the head-flow curve of a pump.

Args: network_id: Session id. pump_id: Pump link name/ID. flow_values: X-axis (flow) values. head_values: Y-axis (head) values.

Set the initial setting of a valve.

PRV/PSV/PBV → pressure setpoint; FCV → flow rate; TCV → loss coefficient.

Args: network_id: Session id. valve_id: Valve link name/ID. setting: New setting value.

Open or close a valve.

Args: network_id: Session id. valve_id: Valve link name/ID. status: "OPEN" or "CLOSED".

Update one or more parameters of a tank node.

Only provided parameters are changed; others retain their current values.

Args: network_id: Session id. tank_id: Tank node name/ID. initial_level: Water level at simulation start. min_level: Minimum operating level. max_level: Maximum operating level. diameter: Tank diameter.

Set the total head (water-surface elevation) of a reservoir.

Args: network_id: Session id. reservoir_id: Reservoir node name/ID. head: Total head value in the network's pressure-head units.

Set the total simulation duration.

Args: network_id: Session id. duration_s: Duration in seconds (e.g. 86400 = 24 h).

Set the hydraulic time step.

Args: network_id: Session id. timestep_s: Hydraulic time step in seconds.

Set the water-quality simulation time step.

Args: network_id: Session id. timestep_s: Quality time step in seconds.

Set the water-quality analysis type.

Args: network_id: Session id. quality_type: One of "NONE", "AGE", "TRACE", or "CHEM". tracer_node: Source node for TRACE analysis. chemical_name: Species name for CHEM analysis. units: Concentration units (e.g. "mg/L").

Add a new simple control rule.

Example control strings::

"LINK P1 CLOSED IF NODE T1 ABOVE 20"
"LINK P1 OPEN IF NODE J2 BELOW 10"
"LINK Pump9 1.5 AT TIME 16:00"

Args: network_id: Session id. control_string: EPANET simple-control syntax string.

Delete a simple control by its 1-based index.

Args: network_id: Session id. control_index: 1-based index (use get_controls to list them).

Apply base-demand multipliers to a set of nodes and optionally simulate.

A clone of the source network is created; the original is unchanged.

Args: network_id: Source network id. node_demands: {node_id: multiplier} — e.g. {"J1": 2.0} doubles demand at J1. scenario_id: Id for the cloned scenario session (auto-generated if omitted). run_simulation: Run a full simulation after applying changes.

Simulate a pipe burst by adding a leakage emitter at the pipe midpoint.

A clone of the source network is created; the original is unchanged. The burst pipe is split into two halves and a midpoint junction node with an emitter is added.

Args: network_id: Source network id. pipe_id: Id of the pipe that bursts. leak_fraction: Fraction of flow that leaks (0.0–1.0). scenario_id: Id for the cloned scenario session. run_simulation: Run a full simulation after applying changes.

Inject a contaminant at a node for a specified time window and simulate.

A clone of the source network is created. Quality type is set to CHEM automatically.

Args: network_id: Source network id. source_node_id: Node where the contaminant is introduced. concentration: Concentration in mg/L (or model quality units). start_time_s: Injection start time in seconds. end_time_s: Injection end time in seconds. source_type: "CONCEN", "MASS", "FLOWPACED", or "SETPOINT". scenario_id: Id for the cloned scenario session. run_simulation: Run a full simulation after applying changes.

Study pressure changes by modifying reservoir heads.

A clone of the source network is created; the original is unchanged.

Args: network_id: Source network id. reservoir_heads: {reservoir_id: new_head} — e.g. {"Reservoir1": 120.0}. scenario_id: Id for the cloned scenario session. run_simulation: Run a full simulation after applying changes.

Apply a time-based pump on/off or speed schedule and simulate.

A clone of the source network is created; the original is unchanged.

Each pump entry maps to a list of EPANET simple-control strings::

{
    "Pump9": [
        "LINK Pump9 1.0 AT TIME 06:00",
        "LINK Pump9 CLOSED AT TIME 22:00"
    ]
}

Args: network_id: Source network id. pump_schedule: {pump_id: [control_string, ...]} schedule. scenario_id: Id for the cloned scenario session. run_simulation: Run a full simulation after applying changes.

Apply static valve-setting changes and simulate.

A clone of the source network is created; the original is unchanged.

Args: network_id: Source network id. valve_settings: {valve_id: new_setting} map. scenario_id: Id for the cloned scenario session. run_simulation: Run a full simulation after applying changes.

Simulate simultaneous pipe and/or pump failures (closure).

A clone of the source network is created; the original is unchanged.

Args: network_id: Source network id. failed_pipes: List of pipe ids to close. failed_pumps: List of pump ids to close. scenario_id: Id for the cloned scenario session. run_simulation: Run a full simulation after applying changes.