Alternate Sources

Due to the large percentage of water used by outdoor irrigation in many systems water conservation is achieved by replacing potable water use with alternate supplies. Commonly used alternative include rainwater harvesting, and grey water. In some commercial sites air conditioning condensate or other on-site water sources such as filtration reject water may be used. Some communities provide treated effluent (reuse water) to large-scale irrigators.

For municipal water systems seeking to encourage the use of alternative supplies a number of considerations must be addressed:

• Proper plumbing – including complete separation from potable systems or adequate backflow protection.
  
• Health code requirements – for grey water or water which is limited for human contact.
  
• Plant tolerance for higher TDS found in grey water or filter reject water.

The most important alternate source to irrigation water is rainwater that falls on the landscape itself. Fortunately, rain sensors are available today, which can not only stop irrigation runs while there is active precipitation, but also for several days if the soil has become saturated, when windy conditions would increase water wastes, and due to temperatures below freezing when the plants are dormant. The simplest approach to rain sensors is to require them by ordinance.¹¹If a utility does not have ordinance making powers, incentive programs are also possible by offering a rebate to customers who install rain sensors.¹²

Efficient Irrigation

Irrigation Zoning

Subsurface, drip - Micro Irrigation