ILLUDAS pit (superseded)

ILLUDAS pit (superseded)

This type of pit is no longer available in DRAINS, but may be encountered in old DRAINS models.  In the older form of the Pit property sheet, it is selected as a simple sag pit (as per ILLUDAS) in the first set of radio buttons.


This has no restriction on inlets to pits, but overflows cannot be directed from an ILLUDAS pit to another pit or node. Stormwater that cannot pass through the downstream pipe system is held at this type of pit, and allowed to drain away as flows diminish at the end of a storm.

This can be modelled as a sag pit with a very large storage and a large or unlimited inlet capacity.  It may be necessary to set up an artificial pit in the Pit Data Base to obtain a large inlet capacity.

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