Landscape and Turf - Avoid Irrigation Overspray

Irrigation systems are being used daily with the hot, dry weather. One concern is irrigation overspray. Irrigation overspray is a waste of water resources and contributes to runoff. Turf and landscape managers should make efforts to design and operate irrigation systems to avoid overspray. The following is an article on the subject.

Irrigation overspray damages pavement, contributes to stormwater pollution, and is an unsightly waste of a valuable resource. It is called nuisance water and it can be prevented.

Nuisance water is chronic running water in gutters and street crossings, standing water where it doesn’t belong, wet areas that never dry and is a common eyesore. The vast majority of nuisance water could be eliminated if managers would follow proper watering schedules, adjust sprinkler timers, and maintain irrigation systems. Overspray is a major culprit. Overspray is water from a sprinkler that lands outside the planted area on a sidewalk or roadway. This is caused by poor sprinkler maintenance and/or design.

Another common cause of nuisance water, although less easy to remedy, is poor landscape design, such as grass planted on a sloping bank along the roadway.

To locate possible nuisance water, look for runoff from an irrigated area when the sprinklers are on. This indicates that all the water is not entering the soil and could be a sign of overwatering, a malfunctioning sprinkler, a broken waterline, or improper landscape design. If the problem is not remedied, sidewalks, gutters, and streets can become slippery with algae. It can also lead to deterioration of asphalt pavement and can contribute to the creation of potholes in the street.

Irrigation overspray also contributes to stormwater pollution by causing fertilizers applied to the landscape areas to be washed away and flow into the gutter. This enters our storm drain system and eventually flows our waters (bays) which can result in reduced water quality. If you are responsible for the maintenance of landscape or turf areas, inspect your irrigation system to ensure that it is operating properly.

Adapted from information from the City of Cypress, CA.