Water supply and pressure issue

wingnutty · Jun 22, 2013

So I have a question I've been struggling with and could use some feedback.

We moved into our home last year, it was built in 1996. Our house shares a community well (~40 users); curb stop at street corner. On our 2 acre lot, we have 3 hydrants, spaced around the property. As best I can tell, these 3 hydrants share the same water line, buried ~6' deep. I am not sure where our house supply line stubs off of the other line. I know the supply lines are 200 psi, and they appear to be black poly. The water pressure is 120 psi, measured at hydrants and in crawl space. So 2 issues:

1. We have pressure reduce in the crawl space, but I just checked it and it is not functioning, meaning the pressure on our lines in the house is 120 psi! YIKES! So, step 1, replace pressure reduce in the crawl space (I tried adjusting the valve and it's a no-go).

2. The pressure at all hydrants is, of course, also 120 psi! This seems insanely high to me and concerns me given that I have a lot of line buried around the lot, 6' deep. Should a leak occur, it probably wouldn't know about it for a loooong time, since I have very sandy soils and I'd likely never be able to find the leak and would have to replace all the lines. I would like to reduce the pressure in all of my lines, but to do so I'd have to install a PR valve at the curb stop, 6' underground. Should I be concerned and install a PR valve at the curb stop, or would ya'll just not worry much about it since the house was built in 1996 and to date, there haven't been any problems? If I did install a PR valve at the curb stop, how would I do this? I'd probably need a big well-pit assembly-type-structure (CMP culvert buried 6' deep) so that I could access the PR valve in the future to adjust or replace. But, the installation of a CMP structure would be quite expensive (I would assume the cost of excavation, install of valve and CMP would be well over $1,000 and we just had twins are a little monetarily tight right now).

So I guess my question really is, would you all be concerned about the 120 psi pressure in the 200 psi lines, or not? Would you install a PR valve at the curb stop and if so, how?

Thanks so much for any feedback, I've been wrestling with this for a w

johnjh2o · Jun 23, 2013

You most live in a cold climate for the line to be 6' deep. I would replace the PRV in the crawl space for sure. You are also correct about what would have to be done to reduce the pressure in the service line. It's your call but if it were mine I would just replace the existing PRV.

plbgbiz · Jun 23, 2013

johnjh2o said:
You most live in a cold climate for the line to be 6' deep. I would replace the PRV in the crawl space for sure. You are also correct about what would have to be done to reduce the pressure in the service line. It's your call but if it were mine I would just replace the existing PRV.

Agreed...

But after replacing the PRV, I would then investigate the possibility of moving south.

IFIXH20 · Jun 23, 2013

Do you have a expanison tank at the water heater ?

wingnutty · Jun 23, 2013

Thanks guys! I lived in a pretty mild part of Montana. Probably don't need 6' for frost protection, but I didn't do the install.

I'm not sure on the expansion tank, I"ll look into it.

So would you all just forget about the PRV at the curb stop then. I guess it has been working fine for 20 years, but I jsut get concerned that someday it'll spring a leak.

johnjh2o · Jun 23, 2013

Even if it was a copper line in 20 years it could also fail. I wouldn't be concerned. But replace the existing PRV.

Haworthplumbing · Jun 24, 2013

For sure change your prv. I would not recommend you bury one after your curb stop. If you are worried you could dig it up find where it tees off and cap off that. Then take the line that runs out to your hydrants and fish it into your house and tie it in after your new prv. How ever I would not loose any sleep having that pressure in the lines out side my house.

AQualityPlumber · Jul 1, 2013

Instead of installing a prv at the curb, I would rather replace the entire water line with wirsbo aquapex with only a connection at the meter and in the crawl. This specific product is rated to handle much higher pressures then regular poly and it is a superior pipe system. I wouldn't be to worried about the poly pipe itself but rather worry about the connections failing since most contractors will just use barb fittings underground. Wirsbo's fittings will be able to handle the psi and never fail as long as it is installed correctly. I've even witnessed excavators grabbing the wirsbo in the ground and ripping it up 10 ft in the air and the fittings were still secured with the main live. Crazy stuff. Then of course, I agree with installing a functional prv in the crawl.

AQualityPlumber · Jul 1, 2013

Also if you buy the wirsbo preinsulated pipe you can go the standard 18-24 inch instead of 6' I know it's more expensive for the pipe, but it may be worth it if you don't want to dig deep. The insulation is encased in plastic corrugated as well so you don't have to worry about it rotting away. Do some research on it. If you go this route you will save money and you will never need to worry about servicing a prv in ground, you won't need to worry about digging deep, you won't need to worry about pressure causing leaks, and you won't need to worry about freeze damage. Dang I think I just came up with the perfect solution for you my friend.