Underground Tanks and Wells: The Fundamental Difference and the Right Cleaning Method for Each

Many Jordanian homes rely on underground tanks or wells, and many of their owners don’t distinguish between the two in terms of cleaning method and risks. This distinction is essential, because neglecting one may affect the other.

What’s the Difference Between an Underground Tank and a Well?

• Underground tank: a manufactured tank (concrete or plastic) buried underground and fed from the government water network
• Well: a deep hole reaching natural groundwater, used for irrigation or drinking after filtration
• An underground tank has a known size and location — a well’s depth ranges between 15 and 80 meters or more
• The contamination source differs: the tank is contaminated from outside and the plumbing, the well from the soil and groundwater

Risks Specific to Underground Tanks

• Fine cracks in concrete walls let soil water seep in — especially in winter
• Constant humidity activates fungi on the interior walls
• Silt accumulates quickly at the bottom because of government water carrying salts
• Some tanks’ proximity to sewage networks increases the risk of microbial contamination

Risks Specific to Wells

• Nitrate contamination from agricultural fertilizers seeping through the soil
• Microbial contamination from nearby cesspits
• High manganese and iron levels in some Jordanian regions
• High salinity in wells near areas with saline soil

An unclean well is a continuous source of contamination that can’t be controlled by a filter alone — regular cleaning and inspection is the only solution.

How Does Cleaning the Two Differ?

An underground tank is cleaned with the same stages as a rooftop tank: draining, scraping, sanitizing, rinsing. But an inspection of the concrete walls for cracks, and sealing them, is added. A well, however, needs special equipment to reach the depths, and sometimes air pumping to expel gases, then sanitizing with a much higher chlorine concentration than ordinary tanks.