Inlet formula (Water Overlay)

Inlets are hydraulic structures can pump water in and out of the project area and are connected with a water body outside the project area.

The amount flowing in or out of inlets is calculated for the cell the inlet resides on.

Inlets

When calculating inlets, first the capacities are calculated.

If a T_lower is defined:

C_inthres = max( 0 , T_lower - WL_surface )

If a I_Q is defined:

C_speed = Δt * I_Q

If a C_total is defined:

C_incap = C_used - C_total

After calculating the capacities, the actual water inflow is calculated.

Δw = max( 0 , min( C_inthres , C_speed , C_incap ) ) / cell

If any of the terms are undefined, they are not included.

When calculating outlets, first the capacities are calculated.

If a T_lower is defined:

C_outthres = min( 0 , T_upper - WL_surface )

If a I_Q is defined:

C_speed = Δt * I_Q

If a C_total is defined:

C_outcap = -C_total - C_used

After calculating the capacities, the actual water ouflow is calculated.

Δw = min( 0 , max( C_outthres , C_speed , C_outcap) ) / cell

If any of the terms are undefined, they are not included.

After the water flow (either inflow or outflow) is computed, the capacity is updated.

C_used (new) = C_used (old) + (Δw * cell)

Where:

C_speed = The amount of water inflow (or outflow when negative) possible based on the inlet's INLET_Q attribute.
C_incap = The amount of water inflow possible based on the total capacity of the inlet.
C_outcap = The amount of water outflow possible based on the total capacity of the outlet.
C_inthres = The amount of water inflow desired based on the inlet's LOWER_THRESHOLD attribute.
C_outthres = The amount of water outflow desired based on the outlet's UPPER_THRESHOLD attribute.