Anyone dealt with a 4-inch PVC building drain with a 12-foot belly holding about an inch of water between 18–30 feet on camera? I can jet and monitor quarterly and add a cleanout, but I’m weighing a spot repair with proper bedding/compaction versus a PM plan — what’s reduced callbacks for you over the long haul?
Go spot repair; a 12’ belly holding about 1" from 18–30’ will keep catching paper, and my callbacks dropped to near zero after re-bedding to grade with 95% compaction and adding a two-way cleanout. > but I’m weighing a spot repair with proper bedding/compaction versus a PM plan — Agree — PM’s only worth it if it’s under slab or 10+ ft deep; what’s your depth and soil?
I’d open-cut and regrade that sagged run; before digging, locate with the sonde and shoot elevations to confirm the dip — once it’s >3/4" on 4" I see paper stall. @philip90 nailed it on compaction, and remember “lining won’t fix a belly”; if you need a bridge plan, add a two-way cleanout near 18’ and stretch PM to 6–12 months so it doesn’t turn into a paper parking lot.
Agree with @philip90 on locating; confirm that ‘1 inch’ from 18–30’ with a slope-reading camera since some heads exaggerate. If it’s real, cut out that 12’ and re-bed with sand and plate compaction, then add a cleanout just upstream for future service. What’s the cover and is this under slab or in the yard?