Hi everyone,
I'm looking to compare gravity sewer renewal and replacement practices across different utilities, and I'd really appreciate any insights from your programs.
A few specific questions:
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What ratio of renewal vs. full replacement do you typically see in your program?
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How much of your gravity system has undergone condition assessment (e.g., % inspected per year or total inspected to date)?
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Do you more often perform full manhole‑to‑manhole replacement, or do you rely heavily on trenchless methods such as spot lining, point repairs, manhole‑to‑manhole lining, or pipe bursting?
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What defect thresholds or decision criteria push you from trenchless rehabilitation to full replacement?
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How often do you upsize structurally deficient segments, and what typically drives that decision?
Thanks in advance for any feedback-large or small. It's all helpful. I'm cross-posting this on a few forums as well.
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Michael Tran P.E., M.ASCE
San Francisco Public Utilities Commission
San Francisco CA
(415)695-7372
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