The model can provide a big picture look at how a system should be functioning (i.e. how much water is available at fire hydrants, what system pressure, how to tank levels affect the system, etc.).  Too often, however, a model is left at the theoretical level when it is actually much more important to get real results.  One of the best ways to determine the accuracy of a water model is to calibrate it with hydrant testing.  An ideal hydrant test would involve flowing one hydrant at a time while recording the available flow as well as the pressure not only of the flowing hydrant but also of several other hydrants throughout the system.  A handful of hydrants should be tested throughout the community.  These results are then compared to the original water model to determine how well the theoretical matches with the real results.  There can be numerous reasons for differences.  A common issue is excessively aged and/or scaled pipe, which can create additional headlosses in the system.  Or, sometimes, the results may indicate a physical problem in the distribution system itself such as a closed or stuck valve.  Regardless, the hydrant testing is important to calibrate the water model, which ensures that when looking at future analyses, the results are most accurate for the system.

One of the most common uses for water modeling at Great West is to help communities determine available fire flows for their water system.  This is an important consideration for all communities but may be most significant for small systems as fire flow demands are typically much larger than their projected customer demands and as a result drive the overall size of the system.  Water modeling can not only identify fire flow  deficiencies for a system but can also be used to evaluate alternatives to improve fire flow as part of future fire flow improvements.  The model can help determine which pipes need to be upsized and to what size.  The model can also be used to help prioritize improvements by determining which improvements will have the most significant hydraulic benefits to the system.

A hydraulic water model helps to evaluate system pressures.  Determining where pressures may be deficient and under what conditions (i.e. with a particularly pump running or not running, or when tank levels drop, etc.).  The model can determine where pressure zones may need to be added or modified.  Similarly, it can help to determine what elevations of new tanks should be.