Exfiltration from Sewers Pipes - Effects of Flowrates, Different Leakage Area and Soil Beddings

摘要

This research was conducted on exfiltration of wastewater from gravity sewers. Exfiltration through different types of sewer leaks and soil beddings were studied. With the different size of leakage areas and a constant thickness of soil bedding, it was found that the exfiltration rate reduces and became constant after several days. This is also true for exfiltration from pipes with the same leakage area but on soil bedding of different thickness. By knowing the exfiltration rate, the time taken for the polluted water exfiltrated from sewer pipes to reach the groundwater can be determined so that measures can be taken to prevent it. From the experiment, it can be shown that the increased in the clogging zone resulted in the decreased of exfiltration rate due to the accumulation of organic matters at the edge of the leakage area and trapped in the pores of the bedding soil.