First, I'm not a plumber, or anything even close.
I live in a house built in 1978, in a 'regular' subdivision outside of
San Jose, CA, and moved in in 1994. The house has copper plumbing. The
water pressure has always been less than I'd like, but that's because I'm
at the top of a hill, close to the water tank.
Over the last six months or so, the pressure has really gotten really
low, at all inside faucets, including dishwasher and clothes washer. The
pressure at the sprinklers, though, and at hose bibs, seems to be the
same as it always has been. We have no complaints when washing cars or
watering the lawn or garden.
I get my water supplied from the main valve at the street. There's a box
there where the water company reads my meter. From there, there's a pvc
(yes, pvc) pipe that runs under my front lawn and brings the water to a
pressure valve on the outside of my house, which then feeds everything
inside the house, and all outside hose bibs. Everything from that point
If I had galvanized pipe in the house, I'd suspect that it was corroded,
and time to replace it, but it's all copper. Can copper corrode? I
always thought not. Another fact that's got me stupmped is why does the
pressure at the outside hoses seem to be as good as when I moved in 14
years ago, yet the inside pressure has really taken a dive in the last
My plan is to have the water company come out and read the pressure at
the street meter, if that's possible. It that's bad, it's their fix. If
that's good, I then get a plumber out to come out and read the pressure
at the valve on the outside of the house. If that's bad, then the
problem is either with the valve, or the pvc line running from the street
meter to the house valve. If that's good, then I still don't understand
why the inside pressure is low at the faucets, but fine at the outside
Many thanks in advance.