Overview:

Reservoirs are open bodies of water that store flow and are connected to nodes by means of an energy-based equation. Reservoirs are considered instantly well-mixed. The Reservoirs Table specifies the identity and physical properties of the reservoir. Connections to nodes are specified in the Reservoir Connections table.


Tables:

RESERVOIR

The RESERVOIR table defines the name and physical properties of the reservoir.

Field Descriptions

NAME
Name of the reservoir. This is the identifier of the reservoir used in other tables.
AREA
Surface area (million sq ft) of the reservoir at typical depth. This area is used to calculate volume changes.
BOT_ELEV
Elevation (ft) of the bottom of the reservoir.

Table Info

Identifier:
NAME
Include Block:
GRID

RESERVOIR_CONNECTION

This table lists reservoir connections to neighboring nodes. Flow through reservoir connections is calculated using the following formula

Q = Cto sqrt[ 2g(znode - zres) ] ... zres < znode

Q = Cfrom sqrt[ 2g(zres - znode) ] ... zres > znode

Where:

  • Cto and Cfrom are coefficients representing the hydraulic efficiency of the reservoir connection and the nominal Area perpendicular to flow.
  • g is gravity and
  • zres and znode are the water surface elevations at the reservoir and node (node surface is assessed by means of a reference channel that has no reservoirs attached to it).

Field Descriptions

RES_NAME
Name of reservoir at which connection is specified.
NODE
Number identifying the node at which connection is specified.
COEF_IN
Coefficient from node to reservoir, greater than zero. If you compare the reservoir equation to the gate or other orifice equation you will find that the reservoir coefficient actually folds several quantities into one parameter: a flow efficiency (between zero and one) and a area of flow. If you have an observation of the area normal to flow, the coefficient should be some fraction of this aperture.
COEF_OUT
flow direction out of the reservoir.

Table Info

Identifier:
RES_NAME, NODE
Parent Table:
RESERVOIR
Parent Identifier:
RES_NAME
Include Block:
GRID

Usage Notes:

  • A node may not have more than three reservoir connections and must have at least one ungated channel connection.