Rich Raj

Burl Smith wrote:In my opinion you need a gate at the top to stop the flow when the water level drops and the pipe starts sucking air.

An inexpensive bilge pump AND a bilge pump float valve (situated conveniently) will do, with the 'T' at the top to prevent passive siphoning.

As I was writing John's reply it clicked what your saying . . . lightbulb moment . . .

Could that be what's happening I'm actually draining the pool when I irrigate?? And the water level drops to below where my pipe is anchored (virtually the bottom)?? But the pool is being constantly refilled by the stream, surely I'm not draining it quicker with just a few dripper lines 🤔 Maybe though, because the times it seems to happen most (syphon stops flowing) is when I leave the drippers on for extended periods (or when I forget to turn them off). I guess the only way to know is go and watch the pool levels when I turn on the irrigation.

If that is the case can you fit a gate to the end of a 1.5 inch pipe or more specifically in between a 1.5 inch joiner and filter? It would ideally have to be some sort of mechanical gate/valve as I can't get power to this location without setting up an independent solar system and power station.

John C Daley wrote:Where is the air getting into the system?
An air valve at the highest point of the pipe system may be needed.
Look at 'design and 'construction of city water supply pipelines'.
If an air bubble is created in the high point, that fills the whole pipe, flow may stop, and air valve allows that air to evacuate the pipe.

thanks buddy I've been away and just getting back to this now!

an air valve sounds like a plan so air getting into causing the flow to stop can escape near the top of the system. I could fit a 1.5 inch Tee and hopefully find a valve to screw into that.

Do you happen to know what this part might be called and have a picture of one?

Hey folks,

So I'm trying to find information on syphon systems and how they work/don't work (in my case) . . .

Basically I've plunged my pipe into a rock pool about 75-100m above my house, and the pipe is about 400m long (to the river) comprising 1.5 inch down to 1 inch, then I've got 350m's of dripper hose split into 3 stations. I started the syphon by filling up the entire pipe with water and just opened a valve at the bottom of the steepest slope. It has been working fine for stop/start hand watering and other things but when I leave one of the dripper stations on for longer than let's say 4 hrs enough air travels back through the system to the top and stops the syphon, or at least that's what I think is happening.

My question is how can I stop this air getting in and traveling back up the system or is there a fitting I can install which removes the air or what is the solution? Just I can't keep climbing the waterfall every one or two weeks to re-fill the pipe especially coming into Winter it might not even be accessible. Failing any solution I guess I could move the point in which I re-fill the pipe to a safer spot. Could I put a tee at the top of the curve before it plunges into the pool and have it open to let the air expel or would the syphon not work in that case?

Let me know any suggestions.

Much love
Rich

Glenn Herbert wrote:From the Google pictures, it looks like the existing wall has a reasonable amount of batter (slope back of the face), and the unstable section starts a meter or more up from the flat. How much actual setback is there from the edge of the flat terrace to the wall face a meter or so up? I would measure the meter of new base thickness from that upper point, which may give you enough clearance for access on the terrace.

from the toe of the wall to the edge of the terrace (or just before the stones) it's about 2m currently so it would be reduced to 1m. So I'll never get a vehicle through there, but I think i'll have to sacrifice that luxury to reinforce this wall (and not rebuild it). I should still be able to get a walk behind tractor through at least.

Unless I look into steel retaining walls but no idea where to start. Though there is a really good metal recyclers nearby where i could get all kinds of steel frame . . .

I'm clearing the area today and hoping to order labour/materials this week to carry out the work. Will get a better night sleep once it's done!

Glenn Herbert wrote:From the Google pictures, it looks like the existing wall has a reasonable amount of batter (slope back of the face), and the unstable section starts a meter or more up from the flat. How much actual setback is there from the edge of the flat terrace to the wall face a meter or so up? I would measure the meter of new base thickness from that upper point, which may give you enough clearance for access on the terrace.

Cool Glen I'm out of town atm but I'll get the measuring tape out as soon as I'm back Wed 👍🏼

Kenneth Elwell wrote:Rich, you could possibly start the siphon by pumping some water back to the stream from tank A to refill the pipe. This might require some clever plumbing with bypass valves, but ought to work as long as tank A doesn't run dry.
Seems like metering your supply from the stream to match your usage, would allow the siphon to just run constantly and *never* break, require re-priming it?
If you had excess flow at tank A could you use it? or return it back to the stream farther downhill? (return of excess would negate need for metering)
If you could pump excess water to tank B, could it irrigate "automatically"? using swales or such? (tank B would then be a reserve)

thanks Kenneth, I think after a day on YouTube yesterday I have figured out how to start the syphon using just a tee piece and a bucket.

I'm going to see how high I can bring the syphon this week.

Re excess water/overflows to keep the syphon running, I thought I could make use of excess water from Tank A but need to double check this as it's a long way back down to the stream from my house. I'm installing dripper irrigation from Tank B which could be running constantly while the sun is out and the solar pump is moving water up from Tank A to B, that could work well.

I'm also considering a Ram Pump close to the pool which could potentially pump water straight up to Tank B and negate the need for two tanks / solar pump install and prob overall less pipe and fittings, but it's more of an experiment I feel. Also like my previous post concerned about the noise of Ram Pumps.

Glenn Herbert wrote:If you have enough space at the bottom of the wall to build a substantial new wall, and can get new stones without difficulty, I think that would be a good solution.

It would be important to have the toe of a new 2 meter high wall at least 1 meter out from the toe of the unstable wall, and the face of the new wall sloping back at least 1 in 6 (or 1/3 of a meter), and all the new stonework bedded so that they want to slide back into the hill. I would carry the new wall up until it supports the unstable section, such that the exposed upper part of the old wall is not in danger of collapsing.

With that done, I don't think you would need to do anything else to the old wall aside from filling gaps to make it look better. This course of action would avoid the work and hazard of dismantling the old wall. Can you get new stone delivered to the bottom area and stockpiled with working space?

Hey Glen, thanks for the response . . . I can get stones delivered to the toe of the old wall with still some working space . . .

My only issue is that bottom corner (front face of the wall not the side which runs into my Car Park), the terrace there is only a few metres wide behind the house so to come out 1m I'd be restricting access quite a bit, would mean never getting a small Tractor down there.

but might have to sacrifice that access for the safest solution 🤷‍♂️

Dean Howard wrote:Sounds like a "ram pump" is what you need.  If you have good enough flow in your stream, it will pump water uphill just fine, no electricity needed.  I saw one on homestead rescue where they pumped uphill with only stream power.

aren't they quite noisy I heard though?

I can syphon water to the house terrace (just need something to get the syphon started) and then I have two solar panels sitting there which I could hook up a small 12-24v pump to pump up and fill the storage tank up top . . .

I'm not sure I need to change the pipe sizing 🤷‍♂️

resurrecting this post as I'm also super interested . . .

planning to use Vetiver to reinforce some stone wall terraces around my sunny spots, but most of my land is forested so pretty well shaded.

Anyone have any experience spreading seed in shady spots with any of these grasses?

Looking for something that is going to spread (not too invasively) and provide a living matting on shady slopes around the bottoms of trees.

Loose loamy soil which is super susceptible to water erosion, so got lots of trees baring roots.

some more pics, with focus on the bottom corner which I think is the main problem area . . .
I'm thinking about a second 2m high stone retaining wall built in front of the corner and all around the side with cement in the gap, in addition to the reo bar bracing and filling the gap with bars/cement.

https://drive.google.com/drive/folders/1SVwWcXo24qJMo42KbiVKRVObH9BPWnnj?usp=share_link