JOAT strongly supports the objectives of disseminating free information technology to assist and improve international leakage and pressure management. To demonstrate the underlying principles of basic aspects of some of these calculations, JOAT has created a series of free Apps which users can easily access from a mobile platform (currently iPhone or iPad).

To access the free JO-Apps Lite smart device app, simply click on the link to the Apple Store. The Android version of the app is currently under development and will be released soon.

The table below shows the different modules contained in JO-Apps Lite.

JO-Apps Lite:

IWA Water Balance

Use this App to create a standard IWA volumetric Water Balance and Key Performance Indicators. Select Units for volumes, lengths, pressure, time period and % of time pressurised. Enter system characteristics, then volumes for each water balance component. KPIs appear when water balance completed.

Snapshot ILI

Use this App to calculate Snapshot ILI. You will also need system characteristics and pressure at the Average Zone Point (AZP) at the time of the night flow measurement.

Night Day Factors

Use this App to calculate the Night Day Factor – by entering hourly values of pressure at the Average Zone Point into the App. The Night Leakage Rate from the Night Flow Analysis is multiplied by the Night-Day Factor to assess the Daily Real Losses from a ‘bottom-up’ calculation. The Night-Day Factor is calculated for a range of FAVAD N1 value (0.5 to 1.5, with default of 1.0)

Future Modules Coming Soon:

FAVAD N1 Step Test Calculation

Use this App to assess the FAVAD N1 exponent which measures the sensitivity of changes in pressure at the Average Zone Point to leak flow rates. At the time of minimum night flow, the inlet pressure is reduced in several steps, and when pairs of values of Night Leakage and Average Zone Pressure are entered in the App, several estimates of the FAVAD N1 are calculated.

Night Flow Analysis

Use this App to split minimum night flow into Night Use and Night Leakage components. Night leakage can be used diagnosing unreported leakage, calculating Snapshot ILI, and calculating daily leakage volume using Night-Day Factor.

Burst Reduction Predictions

Use this app to predict the impact of pressure reduction on the number of main pipeline and service connection bursts.


Water Leakage & Pressure Management. Free Apps for basic leakage calculations.

JO-Apps Pro includes all these modules, plus a control valve sizing guide, flow meter sizing guide, air valve sizing guide and mechanical meter flow rate calculator.

While the JOAT Group of Companies make every effort to deliver high quality products, we do not guarantee that products made available through this website are free from defects. The JO-Apps Lite smart device app is provided “as is”, and you use it at your own risk. We make no warranties as to performance, merchantability, fitness for a particular purpose, or any other warranties whether expressed or implied. No oral or written communicator from information provided by the JOAT Group shall create a warranty. Under no circumstances shall the JOAT Group of Companies be liable for direct, indirect, special, incidental, or consequential damages resulting from the use, misuse, or inability to use this software, even if the JOAT Group has been advised of the possibility of such damages.

All queries and feedback relating to accessing and using JO-Apps must be sent direct to JO-Apps Lite Support at