I harvest rainwater in a four hundred liter ( 90 US Gallon) container that has a drop of about a foot to where I want to add the water. It would save me some time if I could program a timer to turn on every day for five or ten minutes. What should I look for?

I cannot supply an electrical outlet and the timer will be over wintered inside so there is no risk of freezing.

Edit: the purpose of this was to top up my two water features which can lose a half inch a day during the hot dry summer due to evaporation and transpiration from the water plants. The issue behind this question is can you find a timer or regulator that works at low pressure. Gravity feed usually provides 10 to 20 psi where tap water is 100 psi and up.

  • I came across this video, the timer there may be of interest: youtube.com/watch?v=LHh_RDw8tsM
    – bstpierre
    Commented Jul 22, 2012 at 13:14
  • Thanks! That was relevant, now all I have to fix are leaky taps.
    – kevinskio
    Commented Jul 23, 2012 at 13:53
  • Did you use that timer, and is it working out ok? I'm looking for a similar solution -- just got a 1000L IBC tote hooked up, with a ~2m drop to the garden.
    – bstpierre
    Commented Sep 4, 2012 at 19:40
  • I ended up with the Claber timer from Italy seen here: leevalley.com/en/garden/… Expensive but reliable and works on almost no water pressure at all up to tap pressure.
    – kevinskio
    Commented Sep 4, 2012 at 20:23
  • @kevinsky Why don't you answer your question? :)
    – J. Musser
    Commented Jun 9, 2014 at 23:06

2 Answers 2


To recap the problem: Rainwater that is collected in barrels that is four feet (1.1 meter) off the ground comes out of the pipe at about 10 psi using gravity. Most water timers either require 60 to 100 psi (city tap pressure) or an electrical outlet to power the valve and timer.

In order to water plants or top up ponds I needed a water timer that would work with water at 10 psi.

This product from Lee Valley has been in use for two years and has performed flawlessly. It takes a 9 volt battery and has two outlets with separate programs. The only issue I have found is that the pressure of the water from the rain barrels changes depending on how much water is in the barrels. When they are full more water comes out than when they are emptier.

  • Water pressure is 2.31 ft per 1 lb/sq in. so for 10psi, you would require 2.31 ft x 10 = 23.1 ft of elevation on that tank. It's nice to see something that operates off of pressures even lower than 10 PSI for those of us on gravity flow irrigation. Commented Aug 10, 2014 at 5:34
  • @FiascoLabs Right you are, psi, head, bar, too many conversions for me. I probably have more like 2 psi than 10. Thanks!
    – kevinskio
    Commented Aug 11, 2014 at 1:38

Interesting, if I understand correctly. I once took on the onerous job of watering baskets 20' above me. A very cool guy told me to get an old hot-water heater. I could fill it, and with a short hose, sprayer unit I could easily spray into the baskets. Those things hold the city water pressure of 60psi without being hooked up to the city. And hot-water heaters are so very cheap. All I had to do was fill from the city's water. No need for drop to increase water pressure.

As for water features, I found the equation to compute evaporation on some of our large water-falls. I don't have it with me but I saved our company from having to tear the whole waterfall system (the cost was phenomenal) out to discover if there were any leaks. What we discovered is that if you are on city water don't even DREAM of a waterfall. The evaporation was huge! Plant transpiration wasn't even in the equation.

'Dry' water features, dry water falls, dry ponds, dry streams worked well accompanied by 'stero' water sounds from 'artesian' wells. We'd dig a big hole (5'deepX3'wide) line it twice with pond liner, fill with drain rock, 5 gallon pail to hold pump, blast water up to surface to bubble up 6", 1'or 1 1'2'...to fall back into its reservoir. Used a sensor to detect height of reservoir to be refilled automatically. Can't see why you'd need a timer for this, just a low-water sensor. Some days the heat will be so intense you might have to add a gallon or two, other times maybe a gallon every other day. Can't set a timer for that...an old toilet float would work.

  • I'm sorry I don't understand how that helps me when my water source is at low pressure.
    – kevinskio
    Commented Jun 9, 2014 at 20:42
  • So you are trying to funnel rainwater into a non-pressurized system?
    – stormy
    Commented Jun 9, 2014 at 22:11
  • How does a timer help to increase pressure? Is it the build up of a water column? And 5-10 minutes a day how is this going to be of value? This is very interesting...we are having to learn to garden 'off the grid'...what am i missing?
    – stormy
    Commented Jun 9, 2014 at 22:16
  • @stormy He's not looking for higher pressure. He wants a timer that works with low pressure.
    – J. Musser
    Commented Jun 10, 2014 at 1:00
  • I figured that out. Thank you jmusser! I was trying to solve the problem without a timer, a sensor instead to turn on incoming water at whatever pressure...when the water gets too low...
    – stormy
    Commented Jun 10, 2014 at 1:06

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