Two tales of wppoe. A number if years ago, came home to find the basement flooded about 6" deep with sewage. Seem there was a large buffet restaurant about a block from me. Their grease trap failed and grease came down the hill to where my sewer line entered a manhole. The grease hardened into a ball and clogged the outlet which caused the sewage the backup into my basement. The city paid for professional cleaning and sanitizing and to this day they monitor the main line before it reaches my home. Second time was less smelly but was a headache. I have my water supply line replaced by a professional plumbing contractor. Used 3/4" copper from the 1" meter to the house with a ball valve at the point of entry, No problems from quite some time, but one weekend evening I was working in the basement in the vicinity of the valve and bumped it. Suddenly, the valve was on the floor and water under 100 psi was gushing in. I grabbed wrenches and dashed out to meter box, but try as best I could, I could not shut the water off. I then call the emergency number at the water department, but the only person that could help me was on another job across town. Nothing I could do but wait. The man finally arrived, shut the water off. and put the valve back on. Appeared to have been a poor solder job. It was just a few days later that I had a welder friend make me a curb key.