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By Judith A. Stock

 

In order to save millions of gallons of municipal water, the City of Santa Clarita is taking on its irrigation water management system.

Jason La Riva, landscape maintenance district specialist for the city says, "No individual water policy influenced our decision to take on the city's water management system. Our usage was the sole determining factor.

"For the near future, our savings may well offset an increase in demand," he says. "The city is growing by three percent annually and will continue to use more water with each year of growth." Home to 180,000 residents, Santa Clarita is situated between the San Gabriel and Santa Susanna mountain ranges, 30 miles north of downtown Los Angeles. There are 40 landscape maintenance districts in the city that cover more than 700 acres of irrigated landscape and use about 800 million gallons of water annually.

This project is a giant undertaking, easily the largest smart water irrigation management system in the entire country. Over 500 irrigation controllers used to water city parks, medians, common grounds, and streetscaping around homeowners associations, are being replaced by smart weather-based irrigation controllers.

"When we initiated the program, we wanted to identify the lowest-hanging fruit," says La Riva. "We saw the use of smart controllers as being the quickest return on usage or gallons saved." La Riva says the goal of the program is to "start watering our landscapes based on the correct amount of water needed, but no more, without relying on manual program input via our contractors out in the field."

How it works

Everything about this new irrigation system is simply smarter than traditional irrigation management of municipal landscaping. "The irrigation controllers communicate with satellites to water the landscape based on hindcasting weather," says Sharon Thompson, vice president of marketing for HydroPoint Data Systems in Petaluma, California.

Instead forecasting weather before it happens, hindcasting collects data about weather that's already happened from 45,000 local weather stations. "This smart water system always applies the right amount of water at the right time," Thompson says.

The 500 controllers that will replace the old inefficient controllers are Internet-enabled, and part of the real-time central control irrigation system being installed by ValleyCrest Landscape Maintenance in Calabasas, California. On a daily basis, these new controllers measure solar radiation, wind, humidity and temperature, and then they adjust the controller settings to conform to the new data. " As a result, you end up saving a lot of water," says Richard Restuccia, director of water management solutions for ValleyCrest . "When traditional controllers are programmed, they are programmed for the worst-case circumstance, since you can't forecast and know for sure the weather will be cloudy." Only hindcasting gives you that information.

He says the process is similar to a home with a thermostat that measures the temperature and is able to make adjustments accordingly. Imagine the time and money it would take to send three people out in a truck to manually change controller settings. Each time the weather changed, the city would have to send them out again and again.

According to Restuccia, anywhere there's a computer connection, the water system can be controlled, even from a smart phone. If it's going to rain for the next five days, turn the controllers off. Turn the controllers back on when water is needed. This process results in huge savings in water, labor and fuel costs.

As part of the console for the controllers, there is a “scheduling engineer” with 18 pre-set schedules that landscape maintenance personnel can program for the types of plant material at each controller station. Other choices include: precipitation rate, soil type, and terrain. Then the program calculates the information by gathering data on the weather that has taken place over the last two weeks.

The super computer/NOAA station at HydroPoint Data Systems analyzes the weather data and sends the data out to the local smart controllers that micromanage the project. This allows the City of Santa Clarita's local controllers in turn to send out the messages about watering their landscapes.

Message Samples

Message received from the weather net console: It rained for two weeks, sunny the last two days.
Message to local console: no water needed.

Message received from the weather net console: Landscape on sloping terrain, with no run off.
Message to local console: water for three minutes.

Working the system

When the city determined it needed to revise its landscaping maintenance program, the project went out to public bid. "The difference between ValleyCrest's bid price and our number two competitor was very small, only two percent…," Restuccia says. "Fortunately for us, we had done the same installation successfully for the Los Angeles County Parks, installing 140 controllers."

Setup is the thing

Using two teams of three people each, ValleyCrest estimates that the entire smart irrigation controller project installation will take 80 days to complete, 40 days shorter than the contract specifications require. They began the smart controller replacement January 25, 2011 and expect it to be completed in mid-April, 2011.

Restuccia suggested that during the installation process there may be some downtime for the irrigation controllers, but he feels it’s important to complete the project in as few days as possible to avoid California's scorching summer. As a speaker at irrigation association shows and the EPA's Water Smart programs across the country, Restaucci has noticed more and more agencies interested in opting in for new water management systems because of scarcities and climbing water prices. "Water is the oil of the new millennium," he says.

City Saves

Once this water management program has been fully implemented, the City of Santa Clarita anticipates a 20 to 40 percent per unit reduction in water usage based on historical consumption.

After every variable, such as current water cost, per unit rate of water, the average increase per unit from the water companies, and the monthly meter charge, is factored into the equation, La Riva says, "We show a 4 to 6-year return on these controllers, and monies saved looks like about $300,000 to $400,000 per year."

Although it's difficult to quantify, the time saved due to automation would be considerable because workers won't have to manually turn on and off the controllers.

La Riva stresses this: "We do have a strong interest in how many dollars we are saving, but our most important focus is a reduction of the number of gallons of water we use. We focus on gallons and that means a return on money."

Monies used to finance the smart irrigation management program are from special district funds, not from the general fund. With 40 landscape districts within the city, monies saved in each district will be used for other enhancements or projects within each district.

The price tag for this project is $1.9 million for the replacement of more than 500 controllers (purchase, installation, new enclosures, new electrical, three-year subscription service for wireless technology two-way feed on hindcasting of weather, and annual consumption reports for one year), or approximately $2,700 a year per district.

"The city is not a purveyor or seller of water, simply a customer," explains La Riva. "But we do benefit the 20X2020 Water Conservation Plan for California, and since we are a large consumer, our conservation efforts directly benefit our local purveyor and help reach the goal."

Begun in 2009, the California Water Conservation Plan sets forth statewide activities designed to achieve the 20 percent per capita reduction in urban water demand by 2020. Those activities include promoting legislative initiatives to encourage water agencies to promote water conservation, gain a greater understanding of the diversity of water use across the State and create and enforce mechanisms to assure goals are met.

The benefits to the city from the new water management system include fewer problems with standing water in parks or landscaped areas, reduction in the amount of safety concerns on over-spray of medians, a decrease in the amount of ground water on heavily traveled thoroughfares, and being more plant-friendly by not over or under-watering.

And, spending less on the purchase and delivery of water makes more money available for upgrades and repairs to the landscape districts.

Green City Santa Clarita

Some of the other green technology projects the city has undertaken recently include redirecting over 50 percent of the city's solid waste from landfills. Santa Clarita also installed solar panels at its transit maintenance facility, generating 97 percent of the building's power and saving the city over $130,000 per year. There is also a commitment to make all new city facilities LEED Silver certified.

The environment has been a top priority of the city council since Santa Clarita incorporated back in 1987. The city's new water management system is the latest environmental undertaking to make this thriving community as sustainable as possible.


 

 

 

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