Underground tank leak detection for duplexes in Al Dfaa, Riyadh

Prepared by the technical team · editorial review · last updated 13 November 2026 · Sources

What is specific about Al Dfaa for underground tank leak detection

The centre of Al Dfaa is at 24.5927, 46.8324, about 20.8 km from the centre of Riyadh, with an approximate radius of 1.2 km. The service-area circle on the map below is drawn from this point. Main roads in or near Al Dfaa: Kharj Expressway.

The centre of Al Dfaa sits about 576 m above sea level (SRTM open elevation data). The nearest wadi channel is about 1.3 km from the centre of Al Dfaa (OpenStreetMap).

Al Dfaa sits at 24.5927, 46.8324, roughly 20.8 km from the centre of Riyadh, and its built-up core spans an approximate radius of 1.2 km. That compact footprint means many duplexes share narrow streets and tightly spaced plots, so underground tanks are often close to neighbouring foundations and service lines. For a leak detection visit, technicians plan access routes and equipment placement around these tight boundaries, and they confirm the tank position before any testing begins, so that no digging or probing is needed near a neighbour's property.

The centre of the district lies at about 576 m above sea level, and the nearest wadi channel runs about 1.3 km away. Elevation and proximity to a wadi matter because they influence how groundwater and rainwater move beneath a site. Water that collects in low ground can raise the water table around a buried tank, which may hide a leak's signs or make a slow seepage look like normal moisture. Our inspections therefore check the surrounding soil and drainage condition as part of the test, rather than relying on the tank's pressure readings alone, and we note any signs of water ingress in the report.

Owners in Al Dfaa often make the same few mistakes, and our service is designed to avoid them. Many wait for a fuel shortfall or a strong smell before calling anyone, when a slow leak may have run for months; scheduled checks catch it earlier. Others assume a tank with a newer coating needs no attention, yet internal coating work is priced by area, typically SAR 25–70 per m², and a coating defect found early costs far less to repair than a failed tank. Some also refill a tank before testing, which masks the problem. Booking a test before refilling, and keeping records of each check, gives a clear picture of the tank's condition over time.

In a duplex, the two floors often share lines, so tests are done floor by floor.

When do you need underground tank leak detection?

These are the signs most often linked to underground tank leak detection:

• A noticeable drop in the water level overnight
• The pump runs for longer periods
• The tank needs refilling faster than usual

Causes we see in the field

• A common cause: a float valve that does not close, so water is wasted.
• A common cause: construction joints and corners.
• A common cause: cracks in the concrete tank walls or floor.

Tools we use in Al Dfaa

How the work is done, step by step

1. Safety first: Tank lids and confined spaces are handled with ventilation and a second person on site.
2. Documented level test: Filling and use are stopped and the level is recorded against time.
3. Isolating the tank from the network: This tells us whether the loss is from the tank body or from the supply line.
4. Checking the body and connections: Inlet, outlet and overflow connections are inspected.
5. Recommendation: You get the next step in writing: repair, waterproofing or a line test.

Al Dfaa in facts and sources

Short answers for Al Dfaa

Common mistakes we see

• Waterproofing the tank before confirming the loss is from the tank and not the line
• Ignoring the float valve

What you receive

The written output: the written level-test result and the recommended next step. The report is numbered and can be checked with its verification code.