Weak water pressure (under load): Hack-job flip of single-family into 4 condos

Intplm.

With @Mad Dog_2 's good observation skills, and after taking a much closer look, @SteamFTW I would agree that that is probably copper "K" type tubing used for your underground water main.
Hopefully, it's not kinked/damaged causing your issue.

SteamFTW

@Jamie Hall @Mad Dog_2 @hot_rod @jesmed1 @Larry Weingarten @Intplm. @EBEBRATT-Ed @mattmia2 @JUGHNE

I think that's everyone who has wanted more info and photos. The attached are downsized and cropped from 30MB RAW image files. They should be much better than the ones from my phone.

RESULTS:
1. Magnet test showed all the pipes to be non-ferrous.
2. Scratch/scrape test uncovered only "yellow" metals
3. The pipe that comes out of the wall, through the ground clamp, and up to the old valve is MUCH SOFTER than the others.

A razor blade at an angle bites into #3 with very little pressure. If any of you are into woodworking, I'd say if you used a razor blade on it, as you'd use a draw-knife, you'd clearly feel the blade wanting to cut deeper into the metal. Makes me wonder about the lead content. On the other pipes it just slid over the surface, and at best scraped some of the dust off. It took actual work to expose the metal on those pipes.

jesmed1

Then you're in good shape, because there's no steel pipe to rust inside and clog. The soft copper coming through the wall looks like the same 100-year-old stuff our water main contractors removed from our streets recently. I saw them pull some of it out, and it bent surprisingly easily.

mattmia2

The service and the riser are copper. Older meter unions are almost always brass(some newer ones are plastic). That might be an old abandoned lead service to the left of the current service, it is hard to tell and not super important. i would guess that current service is at least 70ish years old, that valve handle is a very old style.

SteamFTW

@jesmed1 True! It may be undersized for the demand, but at least it's not getting smaller due to rust. I'm definitely filing this under "It Could Have Been Worse".

mattmia2 said:

That might be an old abandoned lead service to the left of the current service.

Yep, it's lead. I broke a piece off (with only 3 or 4 bends) and the cross section confirms it. My hope is that it runs all the way through the stone foundation along side the current service. Pull them both out, and maybe the diameter of the tunnel left behind will be already big enough to accommodate a proper sized new service.