GPM - Gallons Per Minute - The available GPM must be known before a sprinkler design can be completed. Sprinkler heads have different GPM requirements. The total GPM of all the sprinkler heads on one zone should not exceed the available GPM. This is extremely important in well water systems.

HEAD-TO-HEAD - This phrase describes the correct placement of spray heads and stream rotors. One sprinkler must be placed so that it will spray another sprinkler (or 50% of the adjusted diameter). This provides for complete coverage and prevents dry spots.

LOW HEAD DRAINAGE - Water left in the pipe after a valve is turned off that is gently flowing out of a low elevation sprinkler head.

PRECIPITATION RATE - Expressed in inches per hour, precipitation rate is the rate at which water is being applied. Matched precipitation means all of the sprinklers in the area are placing about the same amount of water on a given area. Different types of sprinklers should not be installed in the same zone. Large area sprinklers and small area sprinklers may use the same GPM, but because the size of the areas they cover is not the same, the inches per hour of water applied is very different.

RADIUS - How far out from the sprinkler the water sprays. A nozzle with a 17' radius means that the water will spray out as far as 17'.

ROTORS - Gear-driven sprinklers that shoot out a solid stream of water and rotate slowly in a circular pattern, streaming out water to areas as small as 17' and as large as 75' or more. Rotors fit into the “large area sprinklers” category.

SPRAY HEADS - A sprinkler that emits a fan-type spray of small droplets of water. These heads have a radius of 17' and shorter.

With the current blurb for Spray Heads add - The pattern of water out of these heads is determined by the individual nozzle that is installed on top. Hydro-Tech will custom fit each spray head with the necessary nozzle for you application. Regardless of which spray head type, it is important to note that all heads are buried flush with the ground and/or mulch.

Lawn spray - typically a 4" pop-up spray used to cover small grass areas that are less than 17 feet wide. Shrub spray - typically a 12" pop-up spray used to water landscaping beds. The higher elevation allows for better coverage of the mulch bed as a whole, especially when you have plantings of different heights.

ZONE - A zone is an area to be watered by one sprinkler valve.