How Long Will it Take to Drain a 600 Gallon Tank Down a Hill with a 4 Pipe?

[dontknowsht]

I know absolutely nothing about physics, math or anything remotely similar.Perhaps some of you can help me.Here is my situation. There is a hill on our property with no water supply and I want to start a vegetable garden down the hill.The plan is to have a 600 gallon water storage tank at the bottom of the hill with a 4" drain pipe running from the tank to the top of the hill where it can be attached to another 600 gallon truckbed tank for drainage.I haven't bought any of this stuff yet and was wondering how long it will take to drain the truckbed tank down the hill through the 4" pipe and fill the storage tank at the bottom of the hill.All drainpipe fittings are 4".The hill is at a fairly steep slope(I don't know for sure what the exact angle is but maybe you can estimate)the tank is located about 130' from the top of the hill.How long will it take to empty the tank?Thanks.any help is greatly appreciated.

 

[dontknowsht]

Nobody huh?

 

[lzkelley]

I don't understand the situation... So the idea is, you fill the top tank, and let it drain to the bottom tank? Then use the water in the bottom tank for your garden?

Why don't you just fill the bottom tank? You said the top tank was for drainage - draining what?

 

[dontknowsht]

There is no water source to fill the water tank at the bottom of the hill so it has to be done with a full water tank in the back of a truck.The top tank is for water drainage. The plan is to pull up,connect the 4 inch pipe to the fitting on the truck tank,open the gate valve and drain water to the bottom tank.I apologize for the lack of details.does this make sense?

 

[dontknowsht]

when i asked "how long will it take to empty the tank" i am referring to the truck tank at the top of the hill

 

[lzkelley]

Cool, makes sense.
Order of magnitude, 5 minutes (10 tops).

 

[dontknowsht]

Okay cool.Thank you!