Irrigation. Another low flow question

[greenerdreams]

Hello new member, but have used the forum for a long time for info. I am a landscape contractor with 20 years of experience installing, with a small part of our services being irrigation. In the past i have only had a handful of homes with low flow and we usually just dealt with it by breaking into many zones.

We just bought a new to us home, the house has high static pressure (80) but dynamic pressure quickly falls to almost zero. when using my gauge on an outside hose bib it will start at over 13gpm and stabilize to about 4.5gpm. The yard is fairly large(want to irrigate about an acre) and i dont want to break it into a huge amount of zones.

I have looked for advice from past posts but nothing seems to quite fit my situation. we are on city water and i just installed a 1" double check valve immediately after the 5/8x3/4 meter(that was recently replaced with an up to date meter that has remote monitoring) and took a reading straight out of the check valve getting almost the exact same psi and gpm.

curious what others suggest as the most effective method for a more useful supply for the irrigation system( would love to have at least 30psi @10gpm or higher. I would prefer to stay away from a cistern if possible but a pressure tank would be an option.

i guess my last question is whether cities are responsible for supplying a certain flow and psi, since we are paying for the resource?
BTW, the supply in the house is adequate since we rarely use more than one point source at a time.

 

[Terry]

My mothers place in Bellevue has a 5/8" meter, but I brought in a 1.5" service line from the meter because of the distance I was running on her 3/4 acre lot.
The old 3/4" copper line from 1952 wouldn't pop the heads up, but bringing in the 250 foot line from the street in 1.5" fixed that even though the zones broke off into smaller lines after that.

 

[Sponsor]

 

[greenerdreams]

thanks for the input. I did add a direct line from the meter on a 1"poly thinking that would help but i get the same readings at the house(which is a 3/4 copper line)as i do at about 5' from the meter on the direct 1". Do you think the 1.5 would make that much difference?

I did contact the city and they are sending a tech out to determine if their supply is adequate, but i dont have my hopes up for them doing anything on their end.

On your mothers place, did the new line add pressure, flow or both?

 

[Terry]

The pressure stays the same, but you reduce friction lose when you up size the piping. The longer the distance, the more loss you get.
And of course, if you sucking a milk shake through a coffer stirrer, you're not going to get much. A larger straw is always better.
Next door to my mothers place I ran 350' through a 1" poly line, and comparing that to 60' feet of poly, there wasn't much coming out the end of the pipe. For my mothers irrigation, we went 1.5" PVC and that fixed it.

We have irrigation on the back side of this home too. The picture was not taken at the street either.

10431 SE 23rd St
0.72 acre

The back yard.

Looking toward the street from the the driveway.

 

[greenerdreams]

thats a cool yard. update, I called the city and they came out today to check things. the tech was convinced it was on my end but I talked him into pulling the meter and testing directly at the curb stop and the results were poor. He believes there is either corrosion at the saddle to main or an obstruction. Once they sort that out i will retest and see if i need to go your route of upsizing my mainline for the irrigation.