Definition - What does On-line Tank mean?
An On-line tank is defined as a huge storage tank that stores excess water from sewer overflow in times of heavy storms and floods. This overflow would otherwise empty directly into rivers or onto the streets. The tank fills up during overflow periods until the sewerage system is back to normal when it then slowly empty's back into the system. These tanks are located at a depth to allow gravity to fill them. Trenchless technology enables a cost effective approach to repairing old pipelines situated below ground and repairing or connecting an on-line tank.
Trenchlesspedia explains On-line Tank
On-line tanks are an essential part of the sewer system and consist of a flow section that fills when the normal downstream flow is exceeded. On-line tanks prevent combined sewer overflows (CSO) from reaching the river system without being treated. The conveyance pipelines, which convey the overflow to the tank, have to be installed through considerable lengths and must pass through different soil conditions to reach the storage tank at a considerable depth in order for gravity to act.