{"id":1653,"date":"2026-08-06T10:12:44","date_gmt":"2026-08-06T10:12:44","guid":{"rendered":"https:\/\/www.100percentplumbing.com\/?p=1653"},"modified":"2026-10-23T11:10:14","modified_gmt":"2026-10-23T11:10:14","slug":"hidden-water-leaks-and-high-bills-how-to-spor-the-warnings-signs-early","status":"publish","type":"post","link":"https:\/\/www.100percentplumbing.com\/es\/hidden-water-leaks-and-high-bills-how-to-spor-the-warnings-signs-early\/","title":{"rendered":"Hidden water leaks and high bills: How to spot the warning signs early"},"content":{"rendered":"<style>\n.ppb{\n  --pp-blue:#2BA6DE; --pp-blue-dk:#1E8FC4; --pp-navy:#1B3A8F; --pp-orange:#F5871F;\n  --pp-ink:#3A3A3A; --pp-body:#6E7377; --pp-muted:#9AA0A5; --pp-line:#E6E9EB;\n  --pp-wash:#F5F7F8; --pp-r:5px;\n}\n.ppb,.ppb *{box-sizing:border-box}\n.ppb{color:var(--pp-body);line-height:1.8}\n.ppb p{margin:0 0 1.2em}\n.ppb a{color:var(--pp-blue);font-weight:700}\n.ppb .ppb-toc a,.ppb .ppb-svc,.ppb .ppb-more,.ppb 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28px}\n@media(min-width:680px){.ppb-trust{grid-template-columns:repeat(3,1fr)}}\n.ppb-trust__item{border:1px solid var(--pp-line);border-radius:var(--pp-r);padding:18px 20px}\n.ppb-trust__item b{display:block;color:var(--pp-ink);font-size:16px;margin-bottom:4px}\n.ppb-trust__item span{display:block;font-size:14px;line-height:1.6;color:var(--pp-body)}<\/p>\n<p>.ppb-svcs__grid{display:grid;grid-template-columns:1fr;gap:10px}\n@media(min-width:620px){.ppb-svcs__grid{grid-template-columns:1fr 1fr}}\n.ppb-svc{display:block;padding:16px 20px;border:1px solid var(--pp-line);border-radius:var(--pp-r);text-decoration:none;transition:border-color .18s ease,background .18s ease}\n.ppb-svc:hover{border-color:var(--pp-blue);background:var(--pp-wash)}\n.ppb-svc__t{display:block;font-size:16px;color:var(--pp-ink)}\n.ppb-svc:hover .ppb-svc__t{color:var(--pp-blue)}\n.ppb-svc__d{display:block;font-size:13px;color:var(--pp-muted);margin-top:1px}<\/p>\n<p>.ppb-areas__k{display:block;font-size:15px;color:var(--pp-muted);margin:0 0 8px}\n.ppb-areas p{margin:0;font-size:15px;line-height:1.9;color:var(--pp-ink)}<\/p>\n<p>.ppb-btn{display:inline-flex;align-items:center;justify-content:center;gap:9px;min-height:46px;padding:0 30px;border-radius:4px;font-size:15px;text-decoration:none!important;transition:background .18s ease,color .18s ease}\n.ppb-btn--solid:hover{background:#DB7614!important;color:#fff!important}\n.ppb-btn--line:hover{background:rgba(255,255,255,.15)!important;color:#fff!important}\n.ppb-close__btns{display:flex;flex-wrap:wrap;gap:10px}\n.ppb-close h2{font-size:clamp(23px,3.6vw,29px)!important;font-weight:300!important;color:#fff!important;margin:0 0 12px!important;line-height:1.4!important;text-align:left!important}\n.ppb-close__note{font-size:14px}<\/p>\n<p>@media(prefers-reduced-motion:reduce){.ppb *{transition:none!important}}\n@media print{.ppb-close,.ppb-areas,.ppb-svcs{display:none!important}}\n<\/style>\n<div class=\"ppb\">\n<div class=\"ppb-answer\" style=\"border-left:3px solid #2BA6DE;padding:2px 0 2px 20px;margin:0 0 30px\">\n<p><strong>Yes \u2014 a hidden leak can raise your water bill.<\/strong> Water escapes continuously from pipes, toilets, appliance connections, irrigation lines or water heaters, even when nothing is being used, and it is billed exactly like water you used on purpose.<\/p>\n<p>There is one test that settles it, and it needs no tools: close everything, read the meter, wait two hours, read it again.<\/p>\n<\/div>\n<details class=\"ppb-toc\" open>\n<summary>In this article<\/summary>\n<ol>\n<li><a href=\"#meter\">The meter test<\/a><\/li>\n<li><a href=\"#why-miss\">Why hidden leaks are easy to miss<\/a><\/li>\n<li><a href=\"#signs\">Warning signs and what they mean<\/a><\/li>\n<li><a href=\"#detail\">The eight warning signs in detail<\/a><\/li>\n<li><a href=\"#before\">What to check before calling<\/a><\/li>\n<li><a href=\"#emergency\">When is a hidden leak an emergency?<\/a><\/li>\n<li><a href=\"#local\">Hidden leak detection in Calpe and the Costa Blanca<\/a><\/li>\n<li><a href=\"#faq\">Frequently asked questions<\/a><\/li>\n<\/ol>\n<\/details>\n<div class=\"ppb-body\">\n<div class=\"ppb-sec\">\n<h2 id=\"meter\">The meter test<\/h2>\n<\/div>\n<p>Everything else in this article is a sign. This is the only thing that gives you a yes or a no, and it takes two hours of doing nothing.<\/p>\n<ol class=\"ppb-steps\">\n<li><b>Turn everything off<\/b>Close all taps and showers. Stop the washing machine, the dishwasher and any irrigation.<\/li>\n<li><b>Check the toilets<\/b>Make sure no cistern is quietly refilling in the background. That alone will fail the test.<\/li>\n<li><b>Read the meter<\/b>Write down the full reading, including the small red dials \u2014 that is where a slow leak shows up first.<\/li>\n<li><b>Wait two hours<\/b>Without using any water at all. Not one tap.<\/li>\n<li><b>Read it again<\/b>If the number moved, water is leaving the system somewhere you cannot see.<\/li>\n<\/ol>\n<div class=\"ppb-note\">\n<p>If the meter moved but nothing is visible, the leak is concealed \u2014 under a floor, behind a wall, outdoors, or inside a cistern. That is the point to call a plumber rather than start opening surfaces.<\/p>\n<\/div>\n<div class=\"ppb-sec\">\n<h2 id=\"why-miss\">Why hidden leaks are easy to miss<\/h2>\n<\/div>\n<p>Water may be escaping continuously even when no taps or appliances are in use. The usual sources are running toilets, leaking pipe joints, slab leaks, underground supply leaks, faulty water heaters, irrigation leaks and appliance hose leaks.<\/p>\n<p>The US Environmental Protection Agency&#8217;s WaterSense programme reports that the average household wastes nearly 10,000 gallons of water a year \u2014 around 38,000 litres \u2014 through leaks that are never found.<\/p>\n<p>Not every leak makes a puddle:<\/p>\n<ul>\n<li>pipes are concealed behind walls or under floors;<\/li>\n<li>small leaks evaporate before they pool;<\/li>\n<li>toilets leak silently into the bowl;<\/li>\n<li>outdoor irrigation leaks soak straight into the soil;<\/li>\n<li>water heater leaks start slowly;<\/li>\n<li>holiday homes sit empty for months at a time;<\/li>\n<li>hard water and limescale attack valves, joints and appliances.<\/li>\n<\/ul>\n<p>In Calpe and across the Costa Blanca the last two matter most. Long vacancy periods mean nobody is there to notice, and hard water means there is always something being worn away \u2014 see <a href=\"https:\/\/www.100percentplumbing.com\/how-hard-water-affects-pipes-boilers-and-applicances-in-costa-blanca-homes\/\">how hard water affects pipes, boilers and appliances in Costa Blanca homes<\/a>.<\/p>\n<p><a class=\"ppb-more\" href=\"https:\/\/www.100percentplumbing.com\/plumbing-maintenance-checklist-for-holiday-homes-in-calpe-and-costa-blanca\/\" style=\"display:block;background:#F5F7F8;border-radius:5px;padding:16px 20px;margin:24px 0 30px;text-decoration:none\"><br \/>\n  <span class=\"ppb-more__lbl\" style=\"display:inline-block;background:#2BA6DE;color:#fff;font-size:12px;padding:2px 9px;border-radius:2px;margin-bottom:8px\">Read next<\/span><br \/>\n  <span class=\"ppb-more__txt\" style=\"display:block;font-size:16px;color:#3A3A3A;line-height:1.5\">Plumbing maintenance checklist for holiday homes in Calpe and the Costa Blanca<\/span><br \/>\n<\/a><\/p>\n<div class=\"ppb-sec\">\n<h2 id=\"signs\">Warning signs and what they mean<\/h2>\n<\/div>\n<p>A hidden leak shows several small signs before it becomes obvious. This separates a normal change in household habits from something that needs attention.<\/p>\n<div class=\"ppb-table\">\n<table>\n<thead>\n<tr>\n<th scope=\"col\">Warning sign<\/th>\n<th scope=\"col\">What it may mean<\/th>\n<th scope=\"col\">Best next step<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<th scope=\"row\" data-label=\"Sign\">Higher water bill<\/th>\n<td data-label=\"May mean\">Water is being used or lost unexpectedly<\/td>\n<td data-label=\"Next step\">Compare usage and test the meter<\/td>\n<\/tr>\n<tr>\n<th scope=\"row\" data-label=\"Sign\">Meter moves when water is off<\/th>\n<td data-label=\"May mean\">A leak somewhere in the system<\/td>\n<td data-label=\"Next step\">Isolate water use and call a plumber<\/td>\n<\/tr>\n<tr>\n<th scope=\"row\" data-label=\"Sign\">Damp walls or floors<\/th>\n<td data-label=\"May mean\">Hidden pipe, slab or appliance leak<\/td>\n<td data-label=\"Next step\">Inspect the area and do not delay<\/td>\n<\/tr>\n<tr>\n<th scope=\"row\" data-label=\"Sign\">Musty smell<\/th>\n<td data-label=\"May mean\">Moisture trapped behind surfaces<\/td>\n<td data-label=\"Next step\">Check for damp and mould<\/td>\n<\/tr>\n<tr>\n<th scope=\"row\" data-label=\"Sign\">Low water pressure<\/th>\n<td data-label=\"May mean\">Water escaping before it reaches fixtures<\/td>\n<td data-label=\"Next step\">Check if one or all fixtures are affected<\/td>\n<\/tr>\n<tr>\n<th scope=\"row\" data-label=\"Sign\">Running water sounds<\/th>\n<td data-label=\"May mean\">Concealed pipe leak or toilet leak<\/td>\n<td data-label=\"Next step\">Turn off fixtures and listen<\/td>\n<\/tr>\n<tr>\n<th scope=\"row\" data-label=\"Sign\">Warm patch on the floor<\/th>\n<td data-label=\"May mean\">Possible hot water line under the slab<\/td>\n<td data-label=\"Next step\">Arrange leak detection<\/td>\n<\/tr>\n<tr>\n<th scope=\"row\" data-label=\"Sign\">Mould or staining<\/th>\n<td data-label=\"May mean\">Long-term moisture<\/td>\n<td data-label=\"Next step\">Locate the source, do not just clean it<\/td>\n<\/tr>\n<tr>\n<th scope=\"row\" data-label=\"Sign\">Toilet keeps refilling<\/th>\n<td data-label=\"May mean\">Internal toilet leak<\/td>\n<td data-label=\"Next step\">Check the cistern mechanism<\/td>\n<\/tr>\n<tr>\n<th scope=\"row\" data-label=\"Sign\">Water heater area damp<\/th>\n<td data-label=\"May mean\">Tank, valve or connection leak<\/td>\n<td data-label=\"Next step\">Inspect, and call if it is active<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<div class=\"ppb-sec\">\n<h2 id=\"detail\">The eight warning signs in detail<\/h2>\n<\/div>\n<h3 id=\"s1\">1. Your water bill has increased without a clear reason<\/h3>\n<p>A sudden or steady increase is one of the strongest early indicators. Bills rise for seasonal use, guests, irrigation or pool filling \u2014 but if none of those apply, consider a leak.<\/p>\n<div class=\"ppb-check\">\n<div class=\"ppb-check__cell\">\n<h4>What to check<\/h4>\n<p>Compare the current bill with the same period last year, not just the previous month. Holiday and rental properties have seasonal patterns, so context matters.<\/p>\n<\/div>\n<div class=\"ppb-check__cell\">\n<h4>Best next step<\/h4>\n<p>If usage is higher and you cannot explain it, run the meter test and inspect toilets, taps, appliance connections and outdoor water points.<\/p>\n<\/div>\n<\/div>\n<p>For wider supply concerns, our <a href=\"https:\/\/www.100percentplumbing.com\/domestic-water-supply\/\">domestic water supply service<\/a> can identify whether the issue is inside the home, near the supply line or at a fixture.<\/p>\n<h3 id=\"s2\">2. The water meter moves when everything is off<\/h3>\n<p>Covered in full at the top of this article \u2014 it is the one test that gives a definite answer rather than an indication.<\/p>\n<h3 id=\"s3\">3. You hear water running when no taps are open<\/h3>\n<p>Running, dripping, hissing or rushing sounds can indicate a concealed leak, especially if they continue with every fixture closed.<\/p>\n<div class=\"ppb-check\">\n<div class=\"ppb-check__cell\">\n<h4>What to check<\/h4>\n<p>Listen near bathrooms, kitchens, utility areas, water heaters, exterior walls and meter boxes. Also listen after flushing, to hear whether the cistern actually stops filling.<\/p>\n<\/div>\n<div class=\"ppb-check__cell\">\n<h4>Best next step<\/h4>\n<p>If the sound continues, avoid opening walls or floors yourself. A plumber can narrow down the source with far less disruption.<\/p>\n<\/div>\n<\/div>\n<h3 id=\"s4\">4. Damp patches, stains or musty smells appear<\/h3>\n<p>Hidden leaks show as moisture before they show as dripping. Damp walls, warped flooring, ceiling stains, peeling paint, swollen skirting boards and musty smells all point the same way.<\/p>\n<div class=\"ppb-check\">\n<div class=\"ppb-check__cell\">\n<h4>What to check<\/h4>\n<p>Bathrooms, kitchens, utility rooms, around water heaters, inside wardrobes, ceilings below bathrooms, and walls along known pipe routes.<\/p>\n<\/div>\n<div class=\"ppb-check__cell\">\n<h4>Best next step<\/h4>\n<p>Do not just repaint or dry the area. The source needs finding. If damp appears with no obvious cause, arrange leak detection before it spreads.<\/p>\n<\/div>\n<\/div>\n<h3 id=\"s5\">5. Water pressure has dropped<\/h3>\n<p>Low pressure has several possible causes, and a hidden leak is one of them. If water escapes before it reaches your taps, pressure falls across the property.<\/p>\n<div class=\"ppb-check\">\n<div class=\"ppb-check__cell\">\n<h4>What to check<\/h4>\n<p>Whether the drop affects one tap, one bathroom, hot water only, cold water only, or the entire home.<\/p>\n<\/div>\n<div class=\"ppb-check__cell\">\n<h4>Best next step<\/h4>\n<p>If several fixtures are affected, or it appeared suddenly, call a plumber. It may be a leak, a valve, limescale or a supply fault.<\/p>\n<\/div>\n<\/div>\n<p>Hard water also reduces flow over time by building limescale inside pipes and fittings. Our <a href=\"https:\/\/www.100percentplumbing.com\/water-treatment\/\">water treatment service<\/a> covers softening and filtration for Costa Blanca properties.<\/p>\n<h3 id=\"s6\">6. A toilet keeps refilling or running<\/h3>\n<p>A running toilet is one of the most common causes of water waste, and it rarely looks like a leak because the water runs silently from the cistern into the bowl.<\/p>\n<div class=\"ppb-check\">\n<div class=\"ppb-check__cell\">\n<h4>What to check<\/h4>\n<p>Listen for refilling after the toilet has already flushed. Or put a few drops of food colouring in the cistern and wait without flushing \u2014 if colour reaches the bowl, water is leaking through.<\/p>\n<\/div>\n<div class=\"ppb-check__cell\">\n<h4>Best next step<\/h4>\n<p>A faulty flapper, fill valve or flush mechanism usually needs adjusting or replacing \u2014 see <a href=\"https:\/\/www.100percentplumbing.com\/toilet-keeps-runnins-simple-checks-before-calling-a-plumber\/\">toilet keeps running: simple checks first<\/a>.<\/p>\n<\/div>\n<\/div>\n<h3 id=\"s7\">7. The water heater or boiler area is damp<\/h3>\n<p>Leaks near water heaters start small. A valve, a pipe connection, a pressure relief valve or the tank itself may drip slowly for weeks before a larger failure.<\/p>\n<div class=\"ppb-check\">\n<div class=\"ppb-check__cell\">\n<h4>What to check<\/h4>\n<p>Damp flooring, rust, staining, dripping valves, pressure changes, unusual noises or inconsistent hot water.<\/p>\n<\/div>\n<div class=\"ppb-check__cell\">\n<h4>Best next step<\/h4>\n<p>Do not ignore water around a hot water system, especially near electrical components or gas appliances. See our <a href=\"https:\/\/www.100percentplumbing.com\/hot-water-systems\/\">hot water systems service<\/a> and <a href=\"https:\/\/www.100percentplumbing.com\/signs-you-water-heater-needs-repair-or-replacement\/\">the signs a water heater needs repair or replacement<\/a>.<\/p>\n<\/div>\n<\/div>\n<h3 id=\"s8\">8. Outdoor areas are wet when they should be dry<\/h3>\n<p>Outdoor leaks hide well, because water soaks into soil, garden areas, terraces or irrigation zones instead of pooling.<\/p>\n<div class=\"ppb-check\">\n<div class=\"ppb-check__cell\">\n<h4>What to check<\/h4>\n<p>Unusually green patches of grass, wet soil, puddles near exterior walls, dripping outdoor taps, irrigation running unexpectedly, or water near the meter box.<\/p>\n<\/div>\n<div class=\"ppb-check__cell\">\n<h4>Best next step<\/h4>\n<p>If the meter moves with all indoor and outdoor water off, an underground supply line or irrigation leak is likely.<\/p>\n<\/div>\n<\/div>\n<p>Related reading: <a href=\"https:\/\/www.100percentplumbing.com\/who-can-fix-a-leaking-outdoor-tap-in-calpe\/\">who can fix a leaking outdoor tap in Calpe<\/a>, and <a href=\"https:\/\/www.100percentplumbing.com\/how-to-detect-a-slab-leak-befoer-it-damages-your-property\/\">how to detect a slab leak before it damages your property<\/a>.<\/p>\n<div class=\"ppb-sec\">\n<h2 id=\"before\">What to check before calling<\/h2>\n<\/div>\n<p>Gathering a few facts before calling speeds up the diagnosis considerably. Note down:<\/p>\n<ul>\n<li>when the bill first increased;<\/li>\n<li>whether the meter moves with all water off;<\/li>\n<li>whether damp patches are growing;<\/li>\n<li>whether pressure changed suddenly;<\/li>\n<li>whether it affects hot water, cold water or both;<\/li>\n<li>whether any toilet keeps running;<\/li>\n<li>whether irrigation or outdoor taps may be involved;<\/li>\n<li>whether the water heater area is dry;<\/li>\n<li>how long the property was left empty.<\/li>\n<\/ul>\n<div class=\"ppb-note ppb-note--warn\">\n<p><b>Do not break tiles, open walls or dig outside before the leak is located.<\/b> It causes extra damage, and more often than not it does not find the leak.<\/p>\n<\/div>\n<p>If a leak is active and water is spreading, find and close the main shut-off valve. Our guide to <a href=\"https:\/\/www.100percentplumbing.com\/what-is-a-stopcock-and-why-every-homeowner-should-know-where-it-is\/\">what a stopcock is and why every homeowner should know where it is<\/a> explains how it isolates the water in an emergency.<\/p>\n<div class=\"ppb-sec\">\n<h2 id=\"emergency\">When is a hidden leak an emergency?<\/h2>\n<\/div>\n<div class=\"ppb-decide\">\n<div class=\"ppb-decide__col ppb-decide__col--now\">\n<p class=\"ppb-decide__h\">\n      <svg viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"1.9\" aria-hidden=\"true\"><path d=\"M12 4.5 2.8 20h18.4L12 4.5Z\"\/><path d=\"M12 10v4.2M12 17.2v.4\"\/><\/svg><br \/>\n      Call the 24h line now\n    <\/p>\n<ul>\n<li>Water near sockets, switches or the fuse board<\/li>\n<li>A ceiling stain that is visibly growing<\/li>\n<li>Water pooling around a boiler or water heater<\/li>\n<li>A sudden major drop in pressure<\/li>\n<li>The meter keeps moving while the home uses no water<\/li>\n<\/ul><\/div>\n<div class=\"ppb-decide__col ppb-decide__col--wait\">\n<p class=\"ppb-decide__h\">\n      <svg viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"1.9\" aria-hidden=\"true\"><circle cx=\"12\" cy=\"12\" r=\"9\"\/><path d=\"M12 7v5.2l3.2 1.9\"\/><\/svg><br \/>\n      Book a normal appointment\n    <\/p>\n<ul>\n<li>A tap or shower that drips slowly<\/li>\n<li>A toilet that refills now and then<\/li>\n<li>Pressure slightly lower than usual<\/li>\n<li>A bill you want checked before the next quarter<\/li>\n<li>A routine inspection before closing up the house<\/li>\n<\/ul><\/div>\n<\/div>\n<p>Act quickly too if the property is a holiday home or rental that may be left empty again soon \u2014 that is the situation where a slow leak does the most damage for the longest time. If you are unsure whether it is urgent, read <a href=\"https:\/\/www.100percentplumbing.com\/when-to-call-a-professional-plumber\/\">when to call a professional plumber<\/a>. If a pipe has already failed outright, <a href=\"https:\/\/www.100percentplumbing.com\/who-can-repair-a-burst-pipe-in-calpe\/\">who can repair a burst pipe in Calpe<\/a> is the one you want.<\/p>\n<div class=\"ppb-sec\">\n<h2 id=\"local\">Hidden leak detection in Calpe and the Costa Blanca<\/h2>\n<\/div>\n<p>We help homeowners, landlords, property managers and holiday-home owners across the Marina Alta investigate hidden leaks, unexplained high water bills, low pressure, damp patches, slab leaks, running toilets and hot water system leaks.<\/p>\n<p>Our team inspects visible pipework, tests the common leak points, assesses water pressure, checks shut-off valves and recommends practical next steps. If the problem traces back to ageing pipework, we can also advise whether a targeted repair or a replacement is the better long-term option \u2014 our guide on <a href=\"https:\/\/www.100percentplumbing.com\/should-you-repair-or-replace-old-plumbing-pipes\/\">whether to repair or replace old plumbing pipes<\/a> covers the warning signs.<\/p>\n<div class=\"ppb-trust\">\n<div class=\"ppb-trust__item\">\n    <b>We locate before we open<\/b><br \/>\n    <span>Finding the source first keeps the repair small and the floors intact.<\/span>\n  <\/div>\n<div class=\"ppb-trust__item\">\n    <b>Our own guarantee<\/b><br \/>\n    <span>We offer our own comprehensive guarantee for the work we carry out.<\/span>\n  <\/div>\n<div class=\"ppb-trust__item\">\n    <b>136 Google reviews<\/b><br \/>\n    <span>Verified reviews from customers across the Costa Blanca.<\/span>\n  <\/div>\n<\/div>\n<\/div>\n<p><!-- \/.ppb-body --><\/p>\n<div class=\"ppb-sec\">\n<h2>Related Services<\/h2>\n<\/div>\n<div class=\"ppb-svcs\">\n<div class=\"ppb-svcs__grid\">\n    <a class=\"ppb-svc\" href=\"https:\/\/www.100percentplumbing.com\/general-plumbing\/\"><span class=\"ppb-svc__t\">General Plumbing<\/span><span class=\"ppb-svc__d\">Leaks, blockages, repairs<\/span><\/a><br \/>\n    <a class=\"ppb-svc\" href=\"https:\/\/www.100percentplumbing.com\/domestic-water-supply\/\"><span class=\"ppb-svc__t\">Domestic Water Supply<\/span><span class=\"ppb-svc__d\">Pressure, mains, pumps<\/span><\/a><br \/>\n    <a class=\"ppb-svc\" href=\"https:\/\/www.100percentplumbing.com\/hot-water-systems\/\"><span class=\"ppb-svc__t\">Hot Water Systems<\/span><span class=\"ppb-svc__d\">Install, service, replace<\/span><\/a><br \/>\n    <a class=\"ppb-svc\" href=\"https:\/\/www.100percentplumbing.com\/water-treatment\/\"><span class=\"ppb-svc__t\">Water Treatment<\/span><span class=\"ppb-svc__d\">Hard water and limescale<\/span><\/a>\n  <\/div>\n<\/div>\n<div class=\"ppb-areas\" style=\"background:#F5F7F8;border-radius:5px;padding:20px 24px;margin:28px 0\">\n  <span class=\"ppb-areas__k\">Where we work<\/span><\/p>\n<p>Calpe \u00b7 Benissa \u00b7 Moraira \u00b7 Teulada \u00b7 Benitachell \u00b7 Javea \u00b7 Denia \u00b7 Jalon \u00b7 Pedreguer \u00b7 Ondara \u00b7 Pego \u00b7 Orba \u00b7 and the rest of the Marina Alta<\/p>\n<\/div>\n<div class=\"ppb-sec\">\n<h2 id=\"faq\">Frequently Asked Questions<\/h2>\n<\/div>\n<details class=\"ppb-faq__item\">\n<summary>Can a hidden leak cause a high water bill?<\/summary>\n<div class=\"ppb-faq__a\">\n<p>Yes. Water escapes continuously from pipes, toilets, appliances, irrigation lines, water heaters or concealed areas behind walls and floors, and it is billed exactly like water you use.<\/p>\n<\/div>\n<\/details>\n<details class=\"ppb-faq__item\">\n<summary>How can I tell if I have a hidden water leak?<\/summary>\n<div class=\"ppb-faq__a\">\n<p>Warning signs include a higher bill, a moving meter with the water off, damp patches, musty smells, low pressure, running-water sounds, warm floor areas, or toilets that keep refilling.<\/p>\n<\/div>\n<\/details>\n<details class=\"ppb-faq__item\">\n<summary>How do I check my water meter for a leak?<\/summary>\n<div class=\"ppb-faq__a\">\n<p>Turn off all taps, toilets, appliances and irrigation. Read the meter including the small red dials, wait at least two hours without using water, then read it again. If the reading changed, there may be a leak.<\/p>\n<\/div>\n<\/details>\n<details class=\"ppb-faq__item\">\n<summary>Can a running toilet increase my water bill?<\/summary>\n<div class=\"ppb-faq__a\">\n<p>Yes. A running toilet wastes water continuously, often with no visible puddle. If the cistern keeps refilling, or water flows into the bowl after flushing, it should be repaired.<\/p>\n<\/div>\n<\/details>\n<details class=\"ppb-faq__item\">\n<summary>Is low water pressure a sign of a hidden leak?<\/summary>\n<div class=\"ppb-faq__a\">\n<p>It can be, especially if it affects several fixtures or appeared suddenly. It can also be caused by limescale, a faulty valve or a supply problem.<\/p>\n<\/div>\n<\/details>\n<details class=\"ppb-faq__item\">\n<summary>Should I turn off the water if I suspect a hidden leak?<\/summary>\n<div class=\"ppb-faq__a\">\n<p>If there is active leaking, spreading damp, water near electrics or a fast-moving meter, close the main water supply if it is safe to do so and call a plumber.<\/p>\n<\/div>\n<\/details>\n<details class=\"ppb-faq__item\">\n<summary>Who should I call for hidden leak detection?<\/summary>\n<div class=\"ppb-faq__a\">\n<p>A qualified plumber with leak diagnosis experience. 100% Plumbing works across Calpe and the Marina Alta and can locate the source before any surface is opened.<\/p>\n<\/div>\n<\/details>\n<div class=\"ppb-close\" style=\"background:#1B3A8F;background:linear-gradient(90deg,#1B3A8F 0%,#2BA6DE 100%);border-radius:5px;padding:34px 32px;margin:40px 0 0;color:#E4F3FB\">\n<h2 style=\"color:#fff;font-weight:300;line-height:1.4;margin:0 0 12px;text-align:left\">Meter still moving with everything off?<\/h2>\n<p style=\"color:#E4F3FB;max-width:560px;margin:0 0 22px\">Then water is going somewhere. We find the source before anything gets opened up \u2014 which is what keeps the repair small.<\/p>\n<div class=\"ppb-close__btns\" style=\"display:flex;flex-wrap:wrap;gap:10px\">\n    <a class=\"ppb-btn ppb-btn--solid\" style=\"background:#F5871F;color:#fff;border-radius:4px;padding:0 30px;min-height:46px;display:inline-flex;align-items:center;text-decoration:none\" href=\"https:\/\/www.100percentplumbing.com\/contact-us\/\">Request A Free Quotation<\/a><br \/>\n    <a class=\"ppb-btn ppb-btn--line\" style=\"background:transparent;color:#fff;box-shadow:inset 0 0 0 1px rgba(255,255,255,.6);border-radius:4px;padding:0 30px;min-height:46px;display:inline-flex;align-items:center;gap:9px;text-decoration:none;white-space:nowrap\" href=\"tel:+34965835939\"><br \/>\n      <svg width=\"16\" height=\"16\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"1.9\" aria-hidden=\"true\" style=\"width:16px;height:16px;flex:0 0 16px\"><path d=\"M6.5 3.5h3l1.5 4-2 1.5a12 12 0 0 0 6 6l1.5-2 4 1.5v3a2 2 0 0 1-2.2 2A17 17 0 0 1 4.5 5.7 2 2 0 0 1 6.5 3.5Z\"\/><\/svg><br \/>\n      +34 96 583 5939<br \/>\n    <\/a>\n  <\/div>\n<p class=\"ppb-close__note\" style=\"color:#CDE9F7;margin:18px 0 0\">24h emergency help line \u00b7 607 415 520<\/p>\n<\/div>\n<\/div>\n<p><!-- \/.ppb --><\/p>\n<p><script type=\"application\/ld+json\">\n{\n  \"@context\":\"https:\/\/schema.org\",\n  \"@graph\":[\n    {\n      \"@type\":\"BreadcrumbList\",\n      \"itemListElement\":[\n        {\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/www.100percentplumbing.com\/\"},\n        {\"@type\":\"ListItem\",\"position\":2,\"name\":\"Plumbing\",\"item\":\"https:\/\/www.100percentplumbing.com\/category\/plumbing-costa-blanca\/\"},\n        {\"@type\":\"ListItem\",\"position\":3,\"name\":\"Hidden water leaks and high bills: how to spot the warning signs early\"}\n      ]\n    },\n    {\n      \"@type\":\"BlogPosting\",\n      \"headline\":\"Hidden water leaks and high bills: how to spot the warning signs early\",\n      \"description\":\"How to recognise a hidden water leak early, run a water meter test, and know when to call a plumber in Calpe and the Costa Blanca.\",\n      \"datePublished\":\"2026-08-06\",\n      \"dateModified\":\"2026-10-23\",\n      \"inLanguage\":\"en\",\n      \"author\":{\"@type\":\"Organization\",\"name\":\"100% Plumbing S.L.\",\"url\":\"https:\/\/www.100percentplumbing.com\/about-us\/\"},\n      \"publisher\":{\n        \"@type\":\"Organization\",\"name\":\"100% Plumbing S.L.\",\n        \"logo\":{\"@type\":\"ImageObject\",\"url\":\"https:\/\/www.100percentplumbing.com\/wp-content\/uploads\/2019\/09\/logo-600.png\"}\n      },\n      \"mainEntityOfPage\":{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.100percentplumbing.com\/hidden-water-leaks-and-high-bills-how-to-spor-the-warnings-signs-early\/\"}\n    },\n    {\n      \"@type\":\"HowTo\",\n      \"name\":\"How to run a water meter leak test\",\n      \"totalTime\":\"PT2H10M\",\n      \"step\":[\n        {\"@type\":\"HowToStep\",\"position\":1,\"name\":\"Turn everything off\",\"text\":\"Close all taps and showers, and stop washing machines, dishwashers and irrigation.\"},\n        {\"@type\":\"HowToStep\",\"position\":2,\"name\":\"Check the toilets\",\"text\":\"Make sure no cistern is refilling in the background, because that alone will fail the test.\"},\n        {\"@type\":\"HowToStep\",\"position\":3,\"name\":\"Read the meter\",\"text\":\"Write down the full reading, including the small red dials, where a slow leak shows up first.\"},\n        {\"@type\":\"HowToStep\",\"position\":4,\"name\":\"Wait two hours\",\"text\":\"Do not use any water at all during this period.\"},\n        {\"@type\":\"HowToStep\",\"position\":5,\"name\":\"Read it again\",\"text\":\"If the number changed, water is escaping somewhere in the system.\"}\n      ]\n    },\n    {\n      \"@type\":\"FAQPage\",\n      \"mainEntity\":[\n        {\"@type\":\"Question\",\"name\":\"Can a hidden leak cause a high water bill?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Yes. 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It can also be caused by limescale, a faulty valve or a supply problem.\"}},\n        {\"@type\":\"Question\",\"name\":\"Should I turn off the water if I suspect a hidden leak?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"If there is active leaking, spreading damp, water near electrics or a fast-moving meter, close the main water supply if it is safe to do so and call a plumber.\"}},\n        {\"@type\":\"Question\",\"name\":\"Who should I call for hidden leak detection?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"A qualified plumber with leak diagnosis experience. 100% Plumbing works across Calpe and the Marina Alta and can locate the source before any surface is opened.\"}}\n      ]\n    }\n  ]\n}\n<\/script><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Yes \u2014 a hidden leak can raise your water bill. Water escapes continuously from pipes, toilets, appliance connections, irrigation lines or water heaters, even when nothing is being used, and<\/p>","protected":false},"author":5,"featured_media":1658,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_seopress_titles_title":"Hidden Water Leaks and High Bills","_seopress_titles_desc":"High water bill? 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