How many feet SHALL be tested for exfiltration, infiltration, and alignment before any more of the sewer is constructed?

• A. The First 1000 Feet
• B. The First 900 Feet
• C. The First 1500 Feet
• D. The First 1200 Feet

Answer: (D)

Testing the initial portion of a new sewer line for exfiltration, infiltration, and alignment is about catching problems early, before more of the system is built. Exfiltration and infiltration checks verify that joints and pipe walls are watertight and that groundwater or soil isn’t sneaking into or out of the sewer under the test conditions. Alignment testing ensures the pipe follows the intended path with the correct grade and orientation, so future sections aren’t built on faulty sightlines or elevations.

Why this initial segment is the focus: a defined early length provides a representative sample of construction quality and installation practices. If issues show up, they can be fixed on that segment without cascading into a larger portion of the project, saving time, material, and rework later. Standards specify this prescribed length precisely so that the test is long enough to reveal meaningful problems yet limited enough to manage should corrections be needed.

In short, testing the initial prescribed length before proceeding safeguards the project by verifying leaks, soil interactions, and correct alignment upfront, ensuring that the work of the rest of the sewer can continue with confidence.