We moved into our house a year ago and have been experiencing water pressure issues ever since. I need some help figuring out where the problem might lie. I'll do my best to describe the symptoms as well as the complete plumbing system. Symptoms: 1. When you turn the water on at a faucet, there's about 1 second of strong pressure and then, over the next couple seconds, the pressure decreases significantly. 2. Occasionally, the pressure in the shower drops to less than half of normal. You can turn the water off and back on but the pressure will still be terrible. The next day, it will be back to normal. System: The house is 8 years old. It has city water. The meter is out at the curb, down several feet. A copper pipe enters the house through the basement wall. Immediately, there's a shutoff valve and then a PRV. After the PRV, it changes over to 1" PEX. That 1" PEX travels about 20 feet to the mechanical room where it goes into a small "Manabloc" manifold which feeds 1/2 PEX to the two outdoor spigots, the kitchen sink, and the ice-maker. After the manifold, the 1" PEX continues to a water softener. 1" PEX comes out of the water softener and then goes to both a large Manabloc manifold and to two water 40 gal water heaters (1 is 8 years old, the other is only a year old). The hot water feeds back to the manifold. From the manifold, individual runs of 1/2 PEX feed all the sinks, toilets, showers, etc. Comments: 1. I've bypassed the water softener to see if that was the problem. It didn't seem to make a difference. 2. When a plumber was here for something else, I had him check the water pressure. It was 70psi at one of the outdoor spigots, but he didn't do anything like turn the water on somewhere else in the house to see if it dropped. 3. There's no expansion tank anywhere. 4. Another plumber that was here suggested that the problem might be a bad PRV. I'd appreciate any ideas y'all have. Thanks.

I had my water tested and the city says it has high lead levels. The pipes do not attract a magnet. They are threaded and use some sort of thread (oakum?) where plumbing tape would be used today. When I scrape the surface of the straight pipes they appear to be copper and I do see some blue green rust here and there. The elbows appear more yellow or silver (depending on which light I use), some are stamped 'Lee'. There are a few fittings that are transitions from one size to another, and a few couplings. All the pipes are exposed and I did not see anything that was not a casting. I think lead pipe is poured on site. Any ideas on how I can identify the source of the lead? The lead test required 2 bottles to be filled. The first is filled immediately after opening the tap and showed little lead. The second bottle to be filled after 1-2 minutes of letting the water run showed high lead levels. I would say the water runs 100 ft from the basement wall around to the tap and I guess another 20 ft to the main line in the street. The house is in Brooklyn NY and is more than 100 years old. The line that emerges from the basement wall is comparatively new copper. The city sent me a second lead test kit with 3 bottles.