SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

You might be too far north to be able to consider the ground free from the danger of freezing solid, which is a shame, since that would exclude you from what could be an elegant design solution.

Just so you know, a professional install over the acre-plus of that airstrip could be an expense of ten thousand dollars or more. From the viewpoint of the do-it-yourself homeowner, it becomes something of a 'pick your poison' situation, as to how you get a larger supply of water to the runway area, and furthermore, how you allocate the water.

Offhand, I would state that unless you can get at least 20 gallons per minute at 60-70 psi from your supply, you are going to have a tough time covering that acre-plus, especially if the soil is sandy. If you had unlimited time and expense to make use of the existing 6.6 gpm supply, it would mean a double-row of rotor heads, with a head count of at least 70 and a zone count of at least 35.

The more elegant solution involves the sort of heads used on athletic fields and golf courses. Compared to residential sprinkler heads, these 'pro' heads are extremely expensive, but they have the advantage of longer throw, so less of them are required, and some of them have a built-in control valve that opens and closes by way of water pressure applied by a tube. These "hydraulic valve-in-head" sprinklers save the expense of valve wiring, as well as providing protection against lightning strikes, but the control tubing is generally not considered desirable for use where it can freeze.

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To extend the number-crunching, a design could be dumbed down to its simplest form, as a line of full-circle heads down the middle of the runway. Heads spraying 30-foot radii can be spaced 30 feet apart and they will cover a strip just over 50 feet wide, with a minimum head count of 39, in a minimum of 13 zones. With the controller at the house, over 1000 feet from the furthest valve, the wiring will be still be a significant investment.