measuring gpm of a spring/ram pump

[WarriorMonk]

Hey all, I was thinking of possibly building a ram pump to bring a little water from the spring into my pond. Before building the pump, though, I need to know how many gpm the spring produces. This may be a dumb question, but does anybody know how to figure this out? Do I just hold a milk jug in front of the spring and see how long it takes for it to fill? Or is there a better way?

Anyone built a ram pump? Links?

thanks

[Windy in Kansas]

I have read about the process and if I remember correctly a notched board is used. Can't give you a bit of help otherwise through.

[crafty2002]

You need to build a small dam across the water flow so that all the water comes over through a measured "gate" (all I could think of to call it.)

If it isn't very much take a 2" x 6"-8"-10"-12" (what ever fits the site) and cut a notch in it 2" deep x 12" long. If all the water doesn't flow through this notch then cut it 24" etc.
Just drive it down in the dirt as far as it will go and pack rock and clay around it to sill it as good as possible.
Drive a stake 4 feet up stream from that and then take a 4' level and put it against the stake and when you get it level measure the distance from the other end down to the top of the notch.

If you go through all that, PM me with the size of the notch and the measurement between the notch and the level and I will look up my book and tell you close to how may gallons a minute you have.

Dennis

[ace admirer]

weir, i think

[SolarGary]

Hi,
If you can get all the flow to exit at one place, and can get a bucket to catch the flow, thats the simplest way. Just time how long it takes to fill a 5 gallon bucket. 60 seconds is 5 gpm, 30 seconds is 10 gpm, ...
Its also very accurate.

A rough way to measure the flow without having to build anything is to measure the channel cross section, and then time how long a wood chip takes to move a foot in the current through that cross section (do in calm winds). This is very rough, but you may not need anything more accureate.

The flow rate is then:

(height of cross section in ft)(width of cross section in ft) (time for chip to move 1ft in seconds) (448 ) = flow rate in gpm

For example, if the cross section you do the measurement at has an average width of 2 ft, and an average depth of half a foot, and the wood chip moves 2 ft in one second in the cross section area, then the flow rate would be:

(2 ft)(0.5 ft)(2 ft/sec)(448 gpm/cfs) = 896 gpm

The 448 converts from cubic ft per second to gpm.

Some material on ram pumps here:
http://www.builditsolar.com/Projects...terpumping.htm

Remember that you need to have some drop from the spring to the ram pump for it to work.

Gary