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View Full Version : Poorly designed irrigation system. Need help.


CRUZMISL
07-22-2004, 08:56 PM
Hi All,
Great forum! I'm not in the buisiness but LOOOVE a green grass which brings me to my question.

I had a sprinkler system installed about 4 years ago. My lot measures 100x200'. I have 9 zones with 4 rotors on each zone. All of my equipment is Nelson with 6000 heads. I have ALWAYS had problems with dry areas. I kept calling the company out and they kept adjusting which just moved the dry spots around. Frustrated by their incompetence I found Jess Stryker's website. Very informative but WAAY over my head.

My static pressure is about 52psi. When the system is on it drops to about 40. The water supply according to Stryker's formulas is only good for 10gpm. Since I have 4 rotors on each zone I am currently maxed since the nozzles are rated at 2.5 gpm each.

The sad thing is this is the busiest irrigation company in town and they have NO idea what they're doing. All my nozzles are the same, including the ones that are 1/4 circle, 1/2 circle and full circles. This is clearly over/underwatering areas (funny I still have dry spots in the over watered areas). I wanted to change the nozzles but Jess suggested not having nozzles flow less than 2.5gpm due to wind. 2.5gpm per head is the max my system will run.

I am so confused I don't even know where to start to try and fix this problem. Any suggestions?

Thanks !!!

Joe

DGI
07-22-2004, 11:47 PM
My first question is this: Do you generally have head-to-head coverage?

JimLewis
07-23-2004, 02:40 AM
The MP Rotator (http://www.mprotator.com/) would likely be an excellent choice to fix this problem. Educate yourself on that product. It's ideal the situation you're describing.


Designed specifically for low-flow/low pressure situations
designed to be wind resistant
simple to change over from your existing heads


You'd have to change over to pop-up heads and remove the rotors. But that's very simple.

And you'd have to water longer.

But I bet these would solve your problems.

CRUZMISL
07-23-2004, 06:31 AM
I would say yes I do have head to head coverage BUT the streams from one sprinkler head only overlap th other by about 2-3 feet or so, if I recall. It could be more but I do know the streams do not come close to touching the neighboring head as Jess suggests they should.

The MP Rotator looks interesting. Anyone ever used them?

Joe

Mdirrigation
07-23-2004, 08:09 AM
Sounds like a precip rate problem, all the nozzles should not be the same , a 90 degree head should have a smaller nozzel than a head doing 180 or 360 degrees. You say they are the busiest , they are probably the cheapest also , its the same way here , the busiest companies dont take the time to do it right , they are busy because they under bid. Call another contractor with expereience . Wind should not be a problem , since you water in the early am , there is generally no wind.

JimLewis
07-23-2004, 01:27 PM
The MP Rotator looks interesting. Anyone ever used them?

Yes, we use them all the time. We're installing a system next week with 45 psi and have designed the system to be used with the 30' MP Rotators.

We also use them to fix poorly designed systems where there isn't enough pressure or flow for current heads. So then we retrofit the system with the MP Rotators.

I even installed them in my own yard just because I love the way they look and because they have the best matched precip. rate available.

Haven't had one go bad yet. And we've been installing them for a year and a half now.

earthtool
07-23-2004, 05:28 PM
We also retro fit with the MP 2000 and 3000 in low flow systems.
At 40psi the 3000 will give you 360 degree coverage 30 feet, 3.64 gpm, 0.39 in/hr. to 0.48 in/hr.
Great way to get good coverage without allot of dough.

MOlawnman
07-23-2004, 11:00 PM
Just started using the MPRotater myself. And so far I think they're great. I also just recently discovered that RainBird has come out with the same kind of nozzle. I'm interested to see how well they work.

CRUZMISL
07-24-2004, 12:04 AM
This is awesome. The MP's really sound like the way to go AND they look awesome running. How would I install them in place of the Nelson 6000's I have? It appears they just screw right into the existing housings. IS there a guide I can use so I order the right ones? Lastly, where can I buy them online?

Thanks a ton!! The possibility of resolving this is really making my summer.

Joe

CRUZMISL
07-24-2004, 12:54 AM
Also, how much are they?

Joe

timturf
07-24-2004, 02:23 PM
Mp is @ $5 per nozzle, will not fit on 6000, but fit in most spray heads!

I've used for retrofits and like very much! Matched precip rate, even after you adjust arch and distance!

CRUZMISL
07-24-2004, 02:56 PM
Don't fit a 6000?? Figures. Do they sell a complete unit I'd be able to replace the 6000 with?

Thanks,
JOE

Northwest
07-24-2004, 03:45 PM
You can put them in a Rainbird 1804 body. The 1804's only cost $1.50-$2.50 depending were you get them. You can get them at Lowes if you don't know were a irrigation supply house is.

CRUZMISL
07-24-2004, 05:02 PM
OK that sounds good. Would it be wise to have them on a 6 inch riser rather than the current 4"? I like to keep my grass about 3.5 inches and now some of the grass can get in the way depending on the depth of the head.

Joe

Northwest
07-25-2004, 04:45 PM
Yes, you can put the MPRotators on any body. The rainbird 1806 is a six inch body. You will have to find a irrigation supply house because the hardware stores don't carry MPRotators or 6 inch pop up spray heads.

SprinklerGuy
07-26-2004, 09:12 AM
woah!

The sad thing is this is the busiest irrigation company in town and they have NO idea what they're doing. All my nozzles are the same, including the ones that are 1/4 circle, 1/2 circle and full circles. This is clearly over/underwatering areas (funny I still have dry spots in the over watered areas). I wanted to change the nozzles but Jess suggested not having nozzles flow less than 2.5gpm due to wind. 2.5gpm per head is the max my system will run.

The nozzles can have the same gpm as long as they are running together....a valve of quarters a valve of 1/2's etc....the run times would then be adjusted to reflect this. The only time to avoid the same gpm in these different arcs is when they run together on the same zone.

My static pressure is about 52psi. When the system is on it drops to about 40. The water supply according to Stryker's formulas is only good for 10gpm. Since I have 4 rotors on each zone I am currently maxed since the nozzles are rated at 2.5 gpm each.


I would say yes I do have head to head coverage BUT the streams from one sprinkler head only overlap th other by about 2-3 feet or so, if I recall. It could be more but I do know the streams do not come close to touching the neighboring head as Jess suggests they should.


you do NOT HAVE HEAD TO HEAD COVERAGE.....The nelson 6000 with a 2.5 gpm nozzle running at 40 psi should throw between 30 and 40 feet.....I think if the heads are further apart than 30-40 feet and they aren't reaching...you have bigger fish to fry

Good luck

CRUZMISL
07-26-2004, 09:46 AM
Sprinklerguy, each zone has 1/2's 1/4's 3/4's and full circles in all different configurations and all using #7 nozzles. I have since swapped out the nozzles in one zone to get the precip rate to match to see if it helps.

For example, In one zone I had 3 heads that were 1/2 circle and 1 full circle. I put a #8 nozzle in the full circle and #5's in the 1/2's. They throw much farther and overlap each head but I am not positive on how to properly adjust the spray pattern.

Joe

SprinklerGuy
07-26-2004, 02:08 PM
you are on the right track....as long as each head hits the adjacent head...you should be allright.

Keep in mind..on these rotor zones..you may have to run the water for longer times than you think. I don't know the weather where you are...but it is humid in Bufffalo NY where my wife is from. You are close no? Anyhow....keep it up, you're gettting there....

Too bad...the sprinkler installer should have done this.

CRUZMISL
07-26-2004, 08:40 PM
I am at about the same lattitude as you. I live very close to Detroit. It is too bad about the poopy install but I'm hoping with proper adjustment and nozzle size I can make it work.

I have one challenging zone where the coverage is extremely poor so I am planning on giving the MProtators a try on that zone only and see how it works. Unfortunately I need to change the whole body to do it but if it keeps my grass green I don't care.

Any other tips or advice?

Joe

timturf
07-29-2004, 06:42 PM
cruzmisl,

You are cutting turf too high, try 2 to 2.5 inches

CRUZMISL
07-29-2004, 07:09 PM
Tim, do you really think so? Everyone suggests a higher cut for KBG to reduce the need for water. Any thoughts or are they blowing smoke up my pipe?
Joe

timturf
07-30-2004, 03:37 PM
Kbg ideal cutting height is @ 2 to 2.5 inches. Do some research for height of cuts on turfgrass, I don't think you will find any grass higher than 3.5 inches.

Some simple concepts,
shorter the grass, the shorter the roots
longer the grass, the more water it needs
cutting at the low recommended range of a grass will give a better denisty, than cutting at the high end of range!