Calculations Tab

The Calculations tab stores numerical data related to the size and storage capacity of the detention basin. The fields in this tab are described in the table below:

At this time, no automatic calculations are performed using this data.

Field Name

Definition

Length

Width

Depth

Use these fields to record the basin dimensions.

% Impervious

The percentage of area upstream of the structure that is impervious.

Volume

The total volume of water the detention basin will hold in cubic feet.

Inlet Elevation

Outlet Elevation

These fields record the elevations at the inlet source of the basin and the outlet to which the basin drains.

Storage Calc Pg

Outfall Calc Pg

These fields record the page numbers in the plan set where the storage and outfall calculations are stored.

Runoff Coef.

The average runoff coefficient of the contributing area.

Contributing Area

Total area draining to the basin.

Maximum Volume

The maximum volume of fluid that the detention basin can hold.

Release Rate

The rate of flow that the fluid exits the basin.

Detention Basin Calculations Grid

The Calculations Tab also has a grid that stores detention basin calculations for volume and discharge rates.

Note: These calculations are not performed automatically by the system; they are entered by the user.

A sample of the grid appears below. Sort records in the grid by clicking on the headings.  An up or down arrow (highlighted in orange below) will appear signifying ascending or descending order.

basin caculations

How To Add a new Calculation record

  1. Right-click in the grid and select Add Record. The following window will appear:

    Calculations

  2. Enter a Calculation #. This is required.
  3. Fill out other desired fields.
  4. The DB Calc Rec # will be generated by the system when the record is saved.
  5. Save and Close the record.