What test is described as filling a section with water, allowing saturation, and measuring the water level after one hour?

• A. Water test (exfiltration)
• B. Water test (infiltration)
• C. Air Pressure Test
• D. Alignment Testing

Answer: (A)

This test checks for leakage from the sewer into the surrounding soil by using a hydrostatic fill. You fill a section with water, seal the ends, and let the soil around it saturate. Over an hour, any water that escapes through joints or cracks will leave the pipe and seep into the ground, so the water level inside the section drops. Measuring that drop after one hour tells you how much leakage is occurring. This is exactly what an exfiltration test is designed to detect—water leaving the pipe to the surrounding earth. Infiltration tests, by contrast, relate to groundwater entering the pipe, which would involve different behavior or setup. Air pressure tests use air instead of water, and alignment testing checks geometry rather than leakage.