What could be a consequence of demand dosing in subsurface drip drainfields following intermittent sand filters?

Demand dosing in subsurface drip drainfields, especially after intermittent sand filters, introduces effluent at specific intervals based on the system's capacity and the established demand from the drainfield. This method aims to optimize the distribution and absorption of effluent into the soil.

However, one of the major risks associated with this practice is hydraulic overloading. When the dosing is not appropriately calibrated, it can lead to an excessive volume of effluent being introduced into the drainfield in a short period. If the soil cannot absorb this inflow quickly enough, it results in hydraulic overloading, where the soil becomes saturated and ineffective in treating the effluent. This can lead to surface breakout of untreated sewage, potential contamination of groundwater, and overall system failure.

Correctly managing the dosing at regulated intervals is crucial to maintain the balance between effluent input and soil absorption capacity, thus preventing any form of overloading.