Paineviemäri

Paineviemäri, also known as a pressure sewer system, is a wastewater collection method used in areas where conventional gravity-fed sewer systems are impractical or cost-prohibitive. Instead of relying on gravity to move sewage, a pressure sewer system uses pumps and a network of small-diameter pipes to transport wastewater.

The system typically begins with a grinder pump unit installed at or near each property. This unit grinds solids in the wastewater, making it easier to pump, and stores it in a small tank. When the tank fills, the pump activates, discharging the wastewater under pressure into a common collection main. These mains are laid with a slight slope, but their primary function is to convey pressurized effluent, not to rely on gravity for flow.

The pressure generated by the pumps allows the wastewater to be transported over long distances, through challenging terrain such as hills, rocky soil, or areas with a high water table, and with less excavation than traditional systems. This makes pressure sewers a viable alternative for rural communities, developments on sensitive lands, or areas where the cost of installing gravity sewers is exceptionally high.

Maintenance of a pressure sewer system involves the grinder pump units, which require periodic checks and potential repairs or replacements. The overall system is generally robust, but blockages in the collection mains can occur, usually due to improper disposal of materials into the system. Public education on what can and cannot be flushed is therefore important for the successful operation of these systems.