A dosing tank consists of a tank with an automatic siphon or siphons which discharge effluent into the disposal field at a predetermined volume. This large intermittent dose allows drying of the field between doses. This action is taken to extend the life of the leach field. Generally when the disposal field (leach lines only) consists of more than 500 lineal feet, a dosing tank should be used.

Capacity of the dosing tank is calculated on 75% of the total capacity of the leach-line pipe. The capacity of the tank is the volume contained within the area of the siphon’s draw-down distance.

In designing a commercial disposal system check local ordinances for requirements of disposal system dosing.

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