The Redundant Water System Runtime Calculator calculates how many days a redundant water system can support its critical loads during a water outage. This information is an input for characterizing redundant systems in the TRN risk assessment methodology as part of Baseline Development (BD) Action 3. The calculator can account for three types of systems:
- Onsite storage tank(s) connected only to the primary water supply,
- Onsite or offsite secondary water source that supplies onsite storage tank(s),
- Onsite or offsite secondary water source that directly supplies critical load(s),
After providing answers to the questions below, you will obtain an output estimating the number of days current redundant systems will be able to meet critical loads. This analysis provides a high-level estimate. For users who have done or are planning to do more refined assessments of the runtime capabilities for their redundant systems, those estimates may be more appropriate to use as inputs for the TRN analysis. Note that if your system is more complex than one of the system types listed above, it may require a more involved analysis to estimate system runtime. Review the system definitions to check to see if your system meets the criteria of analysis for this tool.
To see the calculations behind the results, click the “Show Calculations” checkbox. Click “Example” to see an example analysis including entered data and results.
Calculator related questions, suggests, and issues can be submitted here:
Enter the data below to characterize your onsite storage tank. Refer to the schematic water tank and the tool tips next to each question for more information.
Enter the data below to characterize the water available from your secondary water source. Refer to the tool tips next to each question for more information.
The results below show the calculated runtime for the redundant system described by the inputs to this calculator. The runtime is shown in days and in hours. Use the runtime in hours as an input to characterize your water redundant system in the TRN Baseline Development Action 3.