erillsviemärijärjestelmässä

Erillsviemärijärjestelmässä, often translated as a separate sewer system, is a type of wastewater management infrastructure designed to handle domestic sewage and industrial wastewater independently from stormwater runoff. This contrasts with combined sewer systems, which carry both types of water in the same pipes.

The core principle of a separate sewer system is to segregate flows. This means that all wastewater originating from homes, businesses, and industries is collected through a dedicated network of sanitary sewers. This wastewater is then transported to a wastewater treatment plant for purification before being discharged back into the environment. Stormwater, on the other hand, is managed through a separate system of storm drains, ditches, and culverts, typically directing runoff directly to natural water bodies like rivers, lakes, or oceans.

The primary advantage of separate sewer systems is improved wastewater treatment efficiency. By not mixing sewage with large volumes of relatively clean stormwater, treatment plants can operate more effectively and economically. This separation also helps to prevent the overwhelming of treatment facilities during heavy rainfall events, a common problem in combined sewer systems that can lead to untreated sewage overflows into waterways. Furthermore, separate systems reduce the risk of groundwater infiltration into the sanitary sewer, which can also strain treatment capacity. However, implementing and maintaining two separate, extensive pipe networks can be more costly initially than a single combined system.