Irrigating for Water Conservation

There are many methods used to irrigate landscapes and turfgrass. Typically most homeowners utilize hose end irrigation tools to accomplish the task. Most importantly,watering early in the morning between the hours of 4:00 a.m. and 10:00 a.m. reduces water loss and decreases the incidence of fungal problems. With that said, there are three important factors to consider when selecting which sprinkler to use for your landscape.

First of all, a very important consideration is evaporation. A large percentage of water applied to a landscape is lost in regards to time of application and drift due to windy conditions. Selecting a sprinkler that emits large drops or a steady stream of water is more efficient and will reduce the drift of smaller particles of water. Also, sprinklers that hurl water high into the air will drift away from the targeted area during windy conditions.

Secondly, the shape and size of your lawn and landscape dictates which sprinklers are most effective for your situation. For example, a large lawn that is rectangular can be watered effectively with fan type sprayers. (see image above) Most of the sprinklers sold today will have a label on the box that will show the available spray patterns or specify the distance or area that can be achieved. Smaller areas may utilize different spray patterns to achieve full coverage. If the area has curves or narrow areas, certain sprinklers have multiple spray pattern that can be selected for a particular situation.

The water pressure that is applied through a sprinkler head can have both positive and negative results. The higher the pressure, the more likely issues with off target water application occur. Small droplet sizes, from high pressure, will result in more evaporation and greater chance of movement due to wind. If the water pressure is too low, the water may not reach the targeted area or too much water may be applied in a smaller location. It is important to adjust the sprinkler at the faucet to achieve the desired droplet size and coverage.

I cannot express how important water conservation is for our area. Doing a little hands on irrigation audit is a great way to limit water misuse. An irrigation audit can be conducted on just about any type of sprinkler and even a in-ground irrigation system. Simply gather some rain gauges or empty tuna or cat food cans and place them in the area that will be watered. Turn on the water and let the cans or rain gauges capture the water. Take into account the different water requirements for turf and landscape areas. Turf for example generally requires 1inch of water per week. Landscape plants generally have larger root systems and do not require as much water as a turgrass needs. With this in mind, let the sprinkler run for 15 minutes and measure the water captured in the cans or rain gauge (built in measuring scale) with a ruler or other measuring device of your choice. If you have captured 0.25 inches of water, then it can be assumed that you will have to water 4 times within a week to capture the 1 inch of water required for turfgrass.