Calculate your landscape's water needs

On-line tool provides customized schedule

by Luis Generoso, City of San Diego Water Department

ater year 2002 was not good for San Diego landscapes. During the past 12 months, only 28 percent of the normal rainfall fell in San Diego. With only three measly inches falling, the past year will go into the books as the driest ever in San Diego. Couple that with the fact that this is the fourth year in a row with below-normal rainfall, and there's never been a drier four-year period in San Diego's history.

    Many San Diegans have already taken steps to reduce water usage inside the home by installing low-flow toilets, faucet aerators and other water-conserving devices. Now, residents are starting to look outside the home for potential savings. The City of San Diego Water Department's studies have shown that as much as 50 percent of residential water usage is for landscape irrigation.

    As such, proper landscape irrigation has become a new focus for water conservation. The Water Conservation Program of the City of San Diego's Water Department is proactively working to monitor and optimize irrigation water use as a way to spark additional, significant water savings. A key component of this effort is the Landscape Watering Calculator. If you have not already visited this on-line resource, the Water Department encourages you to log-on to www.sandiego.gov/water, and click on Conservation to create a customized watering schedule.

    The City of San Diego's Landscape Watering Calculator is an easy-to-use tool that estimates the appropriate amount of water needed for lawns and gardens. Already, more than 6,000 San Diegans have calculated personal watering schedules. By answering a few questions about the landscape, location, and watering system, the calculator provides a detailed, printable watering schedule for each month. Because there is variation in every landscape, the calculator works by averaging numbers for weather, plants, and soils in San Diego. It is designed to provide a foundation for irrigation, as nothing can replace the value of being familiar with the landscape and irrigation systems to help in diagnosing problems.

    Currently, city staff members are providing schedules from the calculator to homeowners during water-use surveys. In the future, schedules from the calculator will be used to illustrate how to implement water budgets for properties with more than one acre of turf or landscaping.

    “The Landscape Watering Calculator is a great tool for professionals and homeowners to manage their irrigation, and has the added benefit of drastically reducing pollution in our beaches and bays by limiting runoff,” said Dan Carney, landscape architect for the city's Water Conservation Program. “Customized irrigation schedules reduce irrigation runoff – that is the water that runs off turf and landscaping and flows directly into the gutter. This water gathers fertilizer, grass clippings, animal waste, motor oil, and other pollutants and runs into the storm water system and directly into the bay or ocean. Water from the storm drains is not treated prior to its introduction into our recreational water areas.”

    There are a number of factors involved in creating a healthy, vibrant, and water-efficient landscape. Proper irrigation is only the beginning. By providing the Landscape Watering Calculator, the Water Department is making practicing good water-use behavior easier.

    The Water Conservation Program reduces water demand though promoting or providing incentives for the installation of hardware that provides permanent water savings, and by providing services and information to help San Diegans make better decisions about water use. For more information about water conservation, visit www.sandiego.gov/water, or call (619) 515-3500.