Winter Project: Sprinkler Spacing - #17

As we all know by now, the biggest component of our success in having good summer playing conditions lies with the irrigation system. This property is challenging to start with: lots of elevation change, shade, rolls, hills, bumps, swales, clay soils, etc. And in the summer the number one thing grass needs to survive and be healthy is water. If our irrigation system doesn't put the water exactly where it's needed, in the most efficient manner possible, we have to make up for it by watering by hand. And let me tell you, 80 acres is alot of grass for two guys (our dedicated irrigators) to water by hand...daily. So we rely heavily on our irrigation system to do the bulk of the job for us during our nighttime irrigation cycles.

This past winter we focused on the functionality of the irrigation system: making sure it all works. We took inventory and fixed any leaks, or misadjustments in the arc of the sprinkler, a few nozzling and drive change outs, unburied sprinklers that were lost, raised and levelled many that had been knocked around. We made sure every sprinkler turned on, popped up, rotated properly, and turned off when we wanted it to. Everything now works and works properly.

While doing all this, we were also able to get the whole system GPS mapped, so we have an accurate record of where every component of the irrigation system is. The map also serves as a important tool in other ways: we can use a digital version of it to turn on sprinklers from a computer, iPhone or iPad and we use it during projects to make sure we don't trench through pipes or wires. Yet one critical example of the benefit of precise GPS mapping showed up right away: how poor our sprinkler spacing is in many areas.

Good sprinkler spacing should look like this:

This is triangular spacing (on another golf course) that is exactly like what is intended here at Winchester: every head makes a perfect equilateral triangle with 65 ft (plus or minus 2 ft) between each sprinkler. The sprinkler and nozzles are designed to irrigate best when installed in this fashion.

This is what just a small section of the spacing looks like here at Winchester (this is hole #14):

You can see triangles, but they are far more imperfect than those above. And the spacing between heads ranges from as low as 56 ft (ignore the edges...they're a different story) to 75 ft. It may not seem like much, but 10 ft in either direction means a 10 ft miss or a 10 ft overlap. So every triangle above that's not a perfect triangle helps explain summer wet and dry spots. Makes it a little easier to see why consistency in the fairways is difficult to achieve. And the longer we use sprinklers, instead of Mother Nature's perfectly uniform rain, to irrigate, the more pronounced the wet/dry spots become.

So one of our biggest focuses this winter is to try to correct the worst of the worst spots throughout the course. Correcting all the spacing would means hundreds of sprinklers: dig one up, remove it, patch the line, dig up it's proper location, cut the line, patch the sprinkler in, bury, and repeat. Very labor intensive and time consuming. But our focus is on the high playability areas and the areas we know we had a very difficult time keeping turf alive last summer.

 The picture above shows our crew moving a sprinkler near #17 approach. The dirt on the right is where the sprinkler was, the left is where it's being moved to. You can see how far off it was from it's properly spaced location. Making these spacing corrections in several areas throughout the rest of the course should make a significant impact on how well the irrigation system performs and improve turf health, playability and overall consistency this upcoming summer.