Does demand-driven simulation mislead leak detection on a stressed water network, and where does pressure-driven demand change the answer?

What it found

WNTR simulates EPANET’s Net3 for 72 hours at demand multipliers 1 to 3 under the default demand-driven model and the pressure-driven model (required pressure 15 m, 10 and 25 m swept), with a leak of 2 % of mean demand at 30 seeded junctions read at five sensors. At 1 and 1.25 times base demand the two models agree to the three decimals printed; at 1.5 times the median sensor drop is 0.798 m against 0.792 m and 29 of 30 locations are seen by both. At 2 and 3 times the pumps run past their rated flow, the demand-driven run has 60–91 % of junction-hours below 0 m (down to −458 m) and the leak passes no flow, while the pressure-driven run serves 86 % and 62 % of demand and still sits below the required pressure over half the time, so neither is believable there. Hence the conclusions of the earlier detector study, drawn at base demand, do not depend on the demand model. Limits: one textbook network whose low-pressure nodes are mostly zero-demand, noise-free sensor response only (no detectors or false-alarm budget), assumed required pressure, 30 locations and one leak size.

A figure from its own output

Paper, code and results

• README and method
• Experiments and results
• Code
• Tests

More in Detection & tolerances

• How small a water-main leak can pressure sensors find, and does a changepoint detector beat a threshold or CUSUM?Water-leak detection from pressure residuals on EPANET's Net3 (WNTR): at a 5% weekly false-alarm budget, 5 sensors and 10% demand error, CUSUM finds all leaks the sensors can see at 4% of demand but 8% at 1% (3% of all leaks); demand error, not sensor noise or detector choice, sets the limit (simulated leaks; BattLeDIM L-Town was unreachable).
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Produced with AI assistance (Claude). Results are from the code in this repository and are simulated or stylised unless the abstract says otherwise; nothing here implies affiliation with or endorsement by any lab, researcher or company cited. MIT licensed.