Know Your System
Your Supply Line and Your Drain Line Are Two Different Systems
“Water line” and “sewer line” get said in the same breath, but they do opposite jobs — and mixing them up sends you to the wrong service.
Water supply lines — this page — carry clean, pressurized water into the building: from the city main, through the meter, along your private line, and through the interior piping to every faucet. When they fail, you see leaks, pressure loss, rusty or discolored water, or a water bill that climbs for no reason.
Drain and sewer lines carry wastewater out by gravity. Their failures look like slow drains, gurgling, and backups — and if that’s your symptom, you want sewer line repair or drain cleaning instead of this page.
The quick test: water appearing where it shouldn’t (a leak, a wet patch, a hissing pipe) means supply-side trouble. Water refusing to leave where it should (a drain that won’t empty) means drainage trouble. Describe it that way on the call and you’ll land on the right diagnosis faster.