The fire hydrant rating curve shows the relationship between residual pressure and the available flow for any hydrant.  Complete residual pressure vs. available flow calculations are directly performed ranging from the imposed static demand to the maximum available flow at atmospheric pressure, for any user-specified flow increments.  Hydrant curves are often required by fire departments who are responsible for ensuring that a specific hydrant can adequately control a potential fire demand and maintain minimum pressures.

To develop a hydrant curve, from the InfoWater Pro -> Analysis menu, select Run Manager to see the dialog box below.  Select the Hydrant Curve tab, specify the desired parameters, and choose the Run button .


Target Junction ID - Enter the identifier of the junction node or alternately pick the junction node by using the Browse icon  for running a Hydrant Curve Analysis.

Normal Hydrant Flow - Enter the normal or average flow at the hydrant.

Report Flow Increment - Enter the flow increment at which InfoWater will calculate the residual pressures.  Entering a value too small (e.g., 100) may cause errors during simulation.

Time - The hydraulic time period at which fire flows will be calculated.  A hydraulic simulation will be performed for all timesteps up to and including the specified time period where fire flow simulation will be performed. Click on the Select Time button  to launch the Select Time dialog box.


Left click on the Status bar and move the bar to specify the Fire Flow time step. Click on OK to save and exit. Click on Cancel to cancel and exit from the Select Time dialog box.