{"id":2103,"date":"2026-10-27T11:19:40","date_gmt":"2026-10-27T10:19:40","guid":{"rendered":"https:\/\/au.feri.um.si\/losdv\/projekti\/iztekanje-vodovod\/"},"modified":"2026-10-27T12:05:19","modified_gmt":"2026-10-27T11:05:19","slug":"iztekanje-vodovod","status":"publish","type":"page","link":"https:\/\/au.feri.um.si\/losdv\/en\/projekti\/iztekanje-vodovod\/","title":{"rendered":"Estimating water pipeline leakage from SAR images"},"content":{"rendered":"<section class=\"wp-block-group alignfull au-section au-section--dark au-projhero is-layout-flow wp-block-group-is-layout-flow\">\n<div class=\"wp-block-group au-container is-layout-flow wp-block-group-is-layout-flow\">\n<p class=\"au-back wp-block-paragraph\"><a href=\"\/losdv\/en\/#iz-nasega-dela\">\u2190 Projects and theses<\/a><\/p>\n\n\n<p class=\"au-eyebrow wp-block-paragraph\">01.4 \u00b7 ESA research project<\/p>\n\n\n<h1 class=\"wp-block-heading\">Estimating water pipeline leakage from SAR images<\/h1>\n\n\n<p class=\"au-lead wp-block-paragraph\">Using polarimetric radar images from the ALOS-2 satellite, we look for places where water leaks from buried water pipes \u2013 to survey the whole network at once.<\/p>\n\n\n<div class=\"anim-box\">\n      <canvas id=\"anim\" aria-label=\"Animation: the ALOS-2 satellite flies over Maribor and acquires a SAR image; behind it a neural network marks the places with a higher probability of leakage on the water network.\"><\/canvas>\n      <div class=\"anim-cap mono\"><span>Illustration \u00b7 ALOS-2 SAR image over Maribor \u2192 leakage probability map (network and locations are illustrative)<\/span><button class=\"anim-toggle\" type=\"button\">Stop<\/button><\/div>\n    <\/div>\n<\/div>\n<\/section>\n\n\n\n<section class=\"wp-block-group alignfull au-section is-layout-flow wp-block-group-is-layout-flow\">\n<div class=\"wp-block-group au-container is-layout-flow wp-block-group-is-layout-flow\">\n<div class=\"wp-block-columns au-projbody is-layout-flex wp-container-core-columns-is-layout-89c98654 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:60%\">\n<h2 class=\"wp-block-heading\">About the project<\/h2>\n\n\n<p class=\"wp-block-paragraph\">Water supply systems lose a large share of their water through leaks in buried pipes, and most of these locations are invisible on the surface until the failure becomes large. Acoustic sensors, pressure measurement and GPR find leaks reliably, but only on short sections, so they are not suitable for surveying an entire city.<\/p>\n\n\n<p class=\"wp-block-paragraph\">Satellite SAR images regardless of weather and daylight and covers the entire network at once. In the L-band the signal is sensitive to changes in near-surface soil permittivity caused by water leaking from pipes. We tested the method on the water supply network of Maribor (Mariborski vodovod), about 1,800 km of pipes, using polarimetric images from the ALOS-2 satellite.<\/p>\n\n\n<h2 class=\"wp-block-heading\">How it works<\/h2>\n\n\n<ol class=\"wp-block-list au-steps\">\n<li><strong>Acquisition<\/strong>: the ALOS-2 satellite (PALSAR-2) images the area in the L-band in all four polarisations (HH, HV, VH, VV); the images are radiometrically calibrated.<\/li>\n\n\n<li><strong>Filtering with the UTILIS model<\/strong>: contributions of solid objects and surface roughness are removed from the backscatter. The unknown model coefficients are determined by a Kolmogorov\u2013Arnold network (KAN).<\/li>\n\n\n<li><strong>A multiscale dual-branch attention network<\/strong> combines the filtered backscatter, the coherency matrix elements and the polarisation ratios and produces a leakage probability map.<\/li>\n\n\n<li><strong>Comparison with classic models<\/strong> of soil moisture (Oh, Dubois, IEM, Freeman\u2013Durden): these estimate moisture but do not locate the leaks.<\/li>\n<\/ol>\n\n\n<p class=\"wp-block-paragraph\">The result is a pre-selection of suspicious network sections, where the water utility then searches for faults in the field.<\/p>\n<\/div>\n\n\n<div class=\"wp-block-column au-facts is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:40%\">\n<figure class=\"wp-block-table au-facts__table\"><table class=\"has-fixed-layout\"><tbody><tr><td>Type<\/td><td>Research project<\/td><\/tr><tr><td>Funding<\/td><td>ESA (European Space Agency)<\/td><\/tr><tr><td>Satellite<\/td><td>ALOS-2 PALSAR-2 (JAXA)<\/td><\/tr><tr><td>Band<\/td><td>L<\/td><\/tr><tr><td>Polarisations<\/td><td>HH, HV, VH, VV<\/td><\/tr><tr><td>Area<\/td><td>Maribor, water supply network<\/td><\/tr><tr><td>Methods<\/td><td>UTILIS model, Kolmogorov\u2013Arnold networks, multiscale attention network<\/td><\/tr><tr><td>Article<\/td><td>A. Hanzi\u0107, D. Gleich, A. Sarja\u0161: <em>Synthetic Aperture Radar Data-Based Leakage Detection from Water Pipeline Networks using Multiscale Dual-Branch Cross-Attention Encoder and Kolmogorov\u2013Arnold Networks<\/em>, submitted to Remote Sensing.<\/td><\/tr><tr><td>Previous work<\/td><td>B. Pongrac, D. Gleich: <em>Regression Neural Network for Soil Moisture Estimation<\/em>, APSAR, 2021.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n<figure data-wp-context=\"{&quot;imageId&quot;:&quot;6aef85043b1de&quot;}\" data-wp-interactive=\"core\/image\" data-wp-key=\"6aef85043b1de\" class=\"wp-block-image size-full wp-lightbox-container\"><img decoding=\"async\" data-wp-class--hide=\"state.isContentHidden\" data-wp-class--show=\"state.isContentVisible\" data-wp-init=\"callbacks.setButtonStyles\" data-wp-on--click=\"actions.showLightbox\" data-wp-on--load=\"callbacks.setButtonStyles\" data-wp-on--pointerdown=\"actions.preloadImage\" data-wp-on--pointerenter=\"actions.preloadImageWithDelay\" data-wp-on--pointerleave=\"actions.cancelPreload\" data-wp-on-window--resize=\"callbacks.setButtonStyles\" src=\"\/losdv\/wp-content\/uploads\/sites\/4\/2026\/10\/sar-maribor.jpg\" alt=\"Slika SAR satelita ALOS-2 nad Mariborom z reko Dravo\"\/><button\n\t\t\tclass=\"lightbox-trigger\"\n\t\t\ttype=\"button\"\n\t\t\taria-haspopup=\"dialog\"\n\t\t\tdata-wp-bind--aria-label=\"state.thisImage.triggerButtonAriaLabel\"\n\t\t\tdata-wp-init=\"callbacks.initTriggerButton\"\n\t\t\tdata-wp-on--click=\"actions.showLightbox\"\n\t\t\tdata-wp-style--right=\"state.thisImage.buttonRight\"\n\t\t\tdata-wp-style--top=\"state.thisImage.buttonTop\"\n\t\t>\n\t\t\t<svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"12\" height=\"12\" fill=\"none\" viewbox=\"0 0 12 12\">\n\t\t\t\t<path fill=\"#fff\" d=\"M2 0a2 2 0 0 0-2 2v2h1.5V2a.5.5 0 0 1 .5-.5h2V0H2Zm2 10.5H2a.5.5 0 0 1-.5-.5V8H0v2a2 2 0 0 0 2 2h2v-1.5ZM8 12v-1.5h2a.5.5 0 0 0 .5-.5V8H12v2a2 2 0 0 1-2 2H8Zm2-12a2 2 0 0 1 2 2v2h-1.5V2a.5.5 0 0 0-.5-.5H8V0h2Z\" \/>\n\t\t\t<\/svg>\n\t\t<\/button><\/figure>\n<\/div>\n<\/div>\n\n\n<div class=\"wp-block-group au-projnav is-layout-flow wp-block-group-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><a href=\"\/losdv\/en\/projekti\/gpr-metode\/\"><span>\u2190 Previous<\/span>Methods for detecting buried objects<\/a><\/p>\n\n\n<p class=\"wp-block-paragraph\"><a href=\"\/losdv\/en\/projekti\/kontrola-odlitkov\/\"><span>Next \u2192<\/span>Camera inspection of aluminium castings<\/a><\/p>\n<\/div>\n<\/div>\n<\/section>","protected":false},"excerpt":{"rendered":"<p>\u2190 Projekti in zaklju\u010dna dela 01.4 \u00b7 Raziskovalni projekt ESA Ocenjevanje iztekanja iz vodovodnega sistema s slikami SAR Iz polarimetri\u010dnih radarskih slik satelita ALOS-2 i\u0161\u010demo mesta, kjer voda izteka iz zakopanih vodovodnih cevi \u2013 za pregled celotnega omre\u017eja naenkrat. Ponazoritev \u00b7 slika SAR ALOS-2 nad Mariborom \u2192 karta verjetnosti iztekanja (omre\u017eje in mesta so ponazorjena)Ustavi [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":2098,"menu_order":4,"comment_status":"closed","ping_status":"closed","template":"page-brez-naslova","meta":{"footnotes":""},"class_list":["post-2103","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/au.feri.um.si\/losdv\/en\/wp-json\/wp\/v2\/pages\/2103","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/au.feri.um.si\/losdv\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/au.feri.um.si\/losdv\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/au.feri.um.si\/losdv\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/au.feri.um.si\/losdv\/en\/wp-json\/wp\/v2\/comments?post=2103"}],"version-history":[{"count":1,"href":"https:\/\/au.feri.um.si\/losdv\/en\/wp-json\/wp\/v2\/pages\/2103\/revisions"}],"predecessor-version":[{"id":2116,"href":"https:\/\/au.feri.um.si\/losdv\/en\/wp-json\/wp\/v2\/pages\/2103\/revisions\/2116"}],"up":[{"embeddable":true,"href":"https:\/\/au.feri.um.si\/losdv\/en\/wp-json\/wp\/v2\/pages\/2098"}],"wp:attachment":[{"href":"https:\/\/au.feri.um.si\/losdv\/en\/wp-json\/wp\/v2\/media?parent=2103"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}