Return Period Analysis Report View

Upstream Node ID

Upstream node

Link Suffix

Used with the Upstream Node ID to identify a specific link

Min RP Surcharge

Minimum return period to cause surcharge in conduit

Min RP Flood

Minimum return period to cause flood at upstream node

Critical Duration

Length of storm in minutes that caused the greatest flooding at the upstream node

Critical Duration Flood/Lost Volume

This is the total flood volume, or total volume lost, at the node in a storm of the critical duration and the minimum return period that causes flooding

RPA

The RPA table displays the minimum return periods that caused surcharging and flooding. The entries in the table are in the format:

Min RP Surcharge - Min RP Flood

An asterisk (*) after the surcharging return period signifies surcharging by flow. Note that this is also indicated by a check in the Surcharge due to flow column.

A return period may be replaced by an x under the following conditions:

• Return period has a value greater than the maximum Return Period value chosen in the RPA Grid Report dialog.
• Minimum return period that caused flooding cannot be determined because flooding did not occur during any of the simulations selected (in the RPA Grid Report dialog) for use in producing the report.

For example, an RPA value of 5-x means that a return period of 5 years caused surcharging in the link, and a return period of more than the maximum caused flooding at the upstream node (or the return period causing flooding at the upstream node could not be determined from selected simulations).

The Asset ID specified for this conduit.

Note that this is also indicated by the use of an asterisk (*) after the surcharging return period in the RPA field, which is retained for compatibility.