ballardFan
New Member
I have an existing 8800 ft long 1.5" water line coming off a 1.5" meter with a gradual elevation drop of 480 ft. The county says the meter provides 100GPM and 120 PSI at the top of the hill. I calculated the elevation drop adds roughly ~203 PSI extra.
The first 8000 ft of line is 1.5" SDR9 PE pipe that is fusion welded. The line has an older pressure reducer right off of the meter to take the base pressure down to ~75 PSI before it starts to run down the steep slope. It has a second PRV at approximately 4000 ft length to reduce pressure back to 75 PSI from what I calculate is 175 PSI at that point.
At the ~4000 ft length there is also a branch of 1" PE pipe that runs for 4000 feet on level ground to service some other parts of the property with limited water needs. The main 1.5" PE line continues down the hill and I have a 3rd PRV at ~8000 ft of length to reduce it back to ~75 psi again from another ~175 PSI gain.
These 3 PRV were all present before I bought the property. I was told without them there were blowouts.
The last 800 ft at the bottom reduces to just 1" SDR9 PE pipe because a previous owner did repairs and cheaped out.
The flow at the bottom of the hill where the property is located is only ~10 GPM and about 40 psi of residual pressure (initial pressure is higher).
The bottom of property has multiple housing units and based on fixture units calc I have 91 fixture units which would require a flow of 41 GPM. I'm at a quarter of that right now.
The main plumber is recommending that first I upsize the last ~800 ft from 1" to 2" PE pipe as a stop gap to increase volume. I suggested 1.5" was enough since that is the size of the rest of the line and it seems like for this to make a large difference I would need to redo the whole line at 2" which is quite expensive.
1) Should I go 1.5" or 2" for the 800 ft?
2) Should I replace the 3 PRV valves or how to evaluate if they are restricting flow too much?
3) Would something like a well style pressure holding tank setup at the bottom for each housing unit help or be a good addition to a solution?
The first 8000 ft of line is 1.5" SDR9 PE pipe that is fusion welded. The line has an older pressure reducer right off of the meter to take the base pressure down to ~75 PSI before it starts to run down the steep slope. It has a second PRV at approximately 4000 ft length to reduce pressure back to 75 PSI from what I calculate is 175 PSI at that point.
At the ~4000 ft length there is also a branch of 1" PE pipe that runs for 4000 feet on level ground to service some other parts of the property with limited water needs. The main 1.5" PE line continues down the hill and I have a 3rd PRV at ~8000 ft of length to reduce it back to ~75 psi again from another ~175 PSI gain.
These 3 PRV were all present before I bought the property. I was told without them there were blowouts.
The last 800 ft at the bottom reduces to just 1" SDR9 PE pipe because a previous owner did repairs and cheaped out.
The flow at the bottom of the hill where the property is located is only ~10 GPM and about 40 psi of residual pressure (initial pressure is higher).
The bottom of property has multiple housing units and based on fixture units calc I have 91 fixture units which would require a flow of 41 GPM. I'm at a quarter of that right now.
The main plumber is recommending that first I upsize the last ~800 ft from 1" to 2" PE pipe as a stop gap to increase volume. I suggested 1.5" was enough since that is the size of the rest of the line and it seems like for this to make a large difference I would need to redo the whole line at 2" which is quite expensive.
1) Should I go 1.5" or 2" for the 800 ft?
2) Should I replace the 3 PRV valves or how to evaluate if they are restricting flow too much?
3) Would something like a well style pressure holding tank setup at the bottom for each housing unit help or be a good addition to a solution?
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