Question

irragation layout   QUESTION: I want to install a drip irrigation system for my blueberries.  I will have a 1200 gal. tank for water located above my sloped beds.   There are presently four 250 ft. rows containing 50 bushes each spaced five feet apart.  The rows are ten feet apart.
The beds are parallel and running down the slope.  There is a 25 foot elevation drop from top to bottom of the rows.
I want to use 1/2 inch drip line with two .5 gph pressure compensating emitters per plant per row.
I know that I will not have enough psi to run the system and would like help in deciding what kind of booster pump I will need for this system.


ANSWER: You will need one that is very small.  By my calculations your entire system will only demand a little over 3 GPM, so what you need is pressure not flow.  I would consider installing a small pressure tank with a pressure switch that will maintain constant pressure for the system.

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QUESTION: The emitters for my irrigation system can run on as little as 12-15 psi.  Would a small volume pump create enough pressure in a pre-charged pressure tank?

Answer
Probably not. You would need something like a 1/2 horse pump for that purpose.  What I was concerned about with your system is that the pump would be constantly pumping against itself, which would make it wear out much faster, and create too much pressure in the system which would cause leaks and other damage.  That is why I recommended a pressure system that could be regulated.